Report to the Chairman, Committee on 

the Judiciary, House of Representatives

United States Government Accountability Office

GAO

October 2005 COMMUNITY 

POLICING GRANTS 

COPS Grants Were a 

Modest Contributor to 

Declines in Crime in 

the 1990s 

GAO-06-104 
What GAO Found

United States Government Accountability Office

Why GAO Did This Study

Highlights

Accountability Integrity Reliability

www.gao.gov/cgi-bin/getrpt?GAO-06-104.

To view the full product, including the scope 

and methodology, click on the link above. 

For more information, contact Laurie Ekstrand 

at (202) 512-8777 or ekstrandl@gao.gov. 

Highlights of GAO-06-104, a report to the 

Chairman, Committee on the Judiciary, 

House of Representatives 

October 2005

COMMUNITY POLICING GRANTS

COPS Grants Were a Modest Contributor 

to Declines in Crime in the 1990s 

About half of the COPS funds distributed from 1994 through 2001 went to 

law enforcement agencies in localities of fewer than 150,000 persons and the 

remainder to agencies in larger communities. This distribution roughly 

corresponded to the distribution of major property crimes but less so to the 

distribution of violent crimes. For example, agencies in larger communities 

received about 47 percent of COPS funds but accounted for 58 percent of the 

violent crimes nationwide. From 1994 through 2001, COPS expenditures 

constituted about 1 percent of total local expenditures for police services. 

For the years 1994 through 2001, expenditures of COPS grants by grant 

recipients resulted in varying amounts of additional officers above the levels 

that would have been expected without the expenditures. For example, 

during 2000, the peak year of COPS expenditures by grant recipients, they 

led to an increase of about 3 percent in the level of sworn officers—or about 

17,000 officers. Adding up the number of additional officers in each year 

from 1994 through 2001, GAO estimated that COPS expenditures yielded 

about 88,000 additional officer-years. GAO obtained its results from fixedeffects regression models that controlled for pre-1994 trends in the growth 

rate of officers, other federal expenditures, and local- and state-level factors 

that could affect officer levels. 

 

From its analysis of the effects of increases in officers on declines in crime, 

GAO estimated that COPS funds contributed to declines in the crime rate 

that, while modest in size, varied over time and among categories of crime. 

For example, between 1993 and 2000, COPS funds contributed to a 1.3 

percent decline in the overall crime rate and a 2.5 percent decline in the 

violent crime rate from the 1993 levels. The effects of COPS funds on crime 

held when GAO controlled for other crime-related factors—such as local 

economic conditions and state-level policy changes—in its regression 

models, and the effects were commensurate with COPS funds’ contribution 

to local spending on police protection. Factors other than COPS funds 

accounted for the majority of the decline in crime during this period. For 

example, between 1993 and 2000, the overall crime rate declined by 26 

percent, and the 1.3 percent decline due to COPS, amounted to about 5 

percent of the overall decline. Similarly, COPS contributed about 7 percent 

of the 32 percent decline in violent crime from 1993 to 2000. 

From 1993 though 1997, agencies that received and spent COPS grants 

reported larger changes in policing practices and in the subsets of practices 

that focus on solving crime problems or focus on places where crime is 

concentrated than did agencies that did not receive the grants. The 

differences held after GAO controlled for underlying trends in the reported 

use of these policing practices. From 1996 to 2000, there was no overall 

increase in policing practices associated with COPS grants. In its review of 

studies on policing practices, GAO found that problem-solving and placeoriented practices can be effective in reducing crime. 

Between 1994 and 2001, the Office 

of Community Oriented Policing 

Services (COPS) provided more 

than $7.6 billion in grants to state 

and local communities to hire 

police officers and promote 

community policing as an effective 

strategy to prevent crime. Studies 

of the impact of the grants on 

crime have been inconclusive. 

GAO was asked to evaluate the 

effect of the COPS program on the 

decline in crime during the 1990s. 

GAO developed and analyzed a 

database containing annual 

observations on crime, police 

officers, COPS funds, and other 

factors related to crime, covering 

years prior to and during the COPS 

program, or from 1990 through 

2001. GAO analyzed survey data on 

policing practices that agencies 

reportedly implemented and 

reviewed studies of policing 

practices. GAO assessed: (1) how 

COPS obligations were distributed 

and how much was spent; (2) the 

extent to which COPS expenditures 

contributed to increases in the 

number of police officers and 

declines in crime nationwide; and 

(3) the extent to which COPS 

grants during the 1990s were 

associated with policing practices 

that crime literature indicates 

could be effective. 

In commenting on a draft of this 

report, the COPS Office said that 

our findings are important and 

support conclusions reached by 

others. 
Page i GAO-06-104 Community Policing Grants 

Letter 1

Background 5 

Results 11 

Concluding Observations 16 

Agency Comments and Our Evaluation 17 

Appendix I Objectives, Scope, and Methodology 20 

Appendix II Background on the COPS Program and Studies of 

the Impacts of COPS Grants on Crime 39 

Appendix III COPS Grant Obligation and Expenditure Patterns 50 

Appendix IV COPS Expenditures Led to Increases in Sworn 

Officers and Declines in Crime 58 

Appendix V COPS Expenditures Associated with Policing 

Practices That Crime Literature Indicates Are 

Effective in Preventing Crime 66 

Appendix VI Methods Used to Estimate the Effects of COPS Funds 

on Officers and Crime 72 

Appendix VII Methods Used to Assess Policing Practices 94 

Appendix VIII Comments from the Department of Justice 108 

Contents 
Page ii GAO-06-104 Community Policing Grants 

Appendix IX GAO Contacts and Staff Acknowledgments 112 

Bibliography 113 

Tables 

Table 1: Index of Crimes, 2002, as Reported by the FBI, Excluding 

Arson 21 

Table 2: COPS Obligations, 1994 through 2001, by COPS Grant 

Categories and Types of Grant Programs 24 

Table 3: Law Enforcement Agencies Reporting to the UCR and in 

Our Analysis Dataset 33 

Table 4: COPS Grant Obligations 1994-2001, by COPS Grant 

Program 50 

Table 5: Percentage Distribution of COPS Obligations and Crime 

from 1994 through 2001, by Population Size Group 52 

Table 6: Per Crime COPS Obligations, by Population Size Group 

and Category of Crime, 1994 through 2001 52 

Table 7: Number of Agencies That Received at Least One COPS 

Grant Obligation, 1994-2001, by COPS Grant Program, and 

Year of First COPS Obligation 53 

Table 8: Percentage of Agencies in GAO’s Primary Analysis Sample 

That Received at Least One COPS Grant Obligation from 

1994 through 2001, by Size of Population Served by 

Agencies 54 

Table 9: Estimated Effect of COPS Expenditures on the Number of 

Sworn Officers Nationwide in Each Year, 1994-2001 59 

Table 10: Estimated Percentage Change in Crime Rates from 1993 

Levels Due to COPS Expenditures, 1994-2001, by Crime 

Type Category 61 

Table 11: Mean Levels of Policing Practices in 1993 and 1997, by 

Category of Policing Practices and whether Agencies 

Received a COPS Grant between 1994 and 1997 67 

Table 12: Mean Levels of Policing Practices in 1993 and 1997, by 

Size of Agency and whether Agencies Received a COPS 

Grant between 1994 and 1997 68 

Table 13: Difference in Mean Levels of Reported Policing Practices 

in 1996 and 2000, by Category of Policing Practices and 

Timing of COPS Grant Expenditures 70 
Page iii GAO-06-104 Community Policing Grants 

Table 14: Alternate Specifications of the Relationship between 

COPS Expenditures and Crime 79 

Table 15: Means and Standard Deviations of Variables Used in 

Regression Models 81 

Table 16: Parameter Estimates from Regressions of Officers Per 

Capita on COPS Hiring Grant Expenditures and Other 

Outside Funds (Standard Errors in Parentheses) 83 

Table 17: Parameter Estimates from Regressions of Crime Rates on 

COPS Hiring Grant Expenditures and Other Outside Funds 

(Standard Errors in Parentheses) 84 

Table 18: Parameter Estimates from Regressions of Index Crime 

Rates and Officers Per Capita on COPS Hiring Grant 

Expenditures and Other Outside Funds, by Population Size 

Category (Standard Errors in Parentheses) 85 

Table 19: Elasticities of the Impact of Police Officers on the Crime 

Rate 86 

Table 20: Elasticity of Violent and Property Crime with Respect to 

Officers under Alternate Specifications of the Relationship 

between COPS Expenditures and Crime 88 

Table 21: Estimated Per Capita Effect of COPS Expenditures on 

the Number of Officers 89 

Table 22: Estimated Per Capita Growth of COPS Expenditures on 

Police Officers and Crime from 1993 92 

Table 23: Categories of Policing Practices and Specific Items within 

Each Category in the Policing Strategies Survey 98 

Table 24: Parameter Estimates from Regressions of Changes in 

Mean Number of Policing Practices and Category of 

Practices between 1993 and 1997 on whether or Not 

Agencies Received COPS grant between 1994 and 1997 and 

on Per Capita COPS Expenditures between 1994 and 1997 

(Standard Errors in Parentheses) 100 

Table 25: Categories of Policing Practices and Specific Items within 

Each Category in the National Evaluation of COPS Survey 103 

Table 26: Parameter Estimates from Regressions of Changes in 

Mean Number of Policing Practices and Category of 

Practices between 1996 and 2000 on Whether or Not 

Agencies Received COPS grant Between 1997 and 2000 

and on Per Capita COPS Expenditures between 1994-1996 

and 1997-2000 (Standard Errors in Parentheses) 105 
Page iv GAO-06-104 Community Policing Grants 

Figures 

Figure 1: Total, Violent, and Property Crime Rates per 100,000 

Persons, as Reported in the Uniform Crime Reports, 1970-

2001 10 

Figure 2: Estimated Effects of COPS Grant Expenditures on the 

Number of Sworn Officers, 1991-2001 13 

Figure 3: Annual Percentage Changes in the Violent Crime Rate 

from 1993: Total Change and Estimated Change Due to 

COPS Grants 14 

Figure 4: Reported Levels of Policing Practices in 1993 and 1997 in 

Agencies That Did and Did Not Receive COPS Grants, by 

Category of Policing Practice 16 

Figure 5: Violent Crimes and Violent Crimes Reported to the Police, 

as Reported in the National Criminal Victimization Survey 

and Including Homicides from the Uniform Crime 

Reports, 1990-2001 36 

Figure 6: Total Index, Violent, and Property Crime Rates per 

100,000 Persons, 1990-2001 46 

Figure 7: Annual Expenditures of COPS Grant Funds, by Year 55 

Figure 8: Number of Agencies That Spent COPS Funds, 1994 

through 2001 56 

Figure 9: Reported Levels of Policing Practices in 1993 and 1997 in 

Agencies That Received and Did Not Receive COPS 

Grants, by Size of Population Served 69 
Page v GAO-06-104 Community Policing Grants 

Abbreviations 

AHEAD Accelerated Hiring, Education, and Deployment 

BJA Bureau of Justice Assistance 

BJS Bureau of Justice Statistics 

COPS Office of Community Oriented Policing Services 

DLEA Directory of Law Enforcement Agency 

DOJ Department of Justice 

FAST Funding Accelerated for Smaller Towns 

FBI Federal Bureau of Investigation 

FIPS Federal Information Processing Standards 

LLEBG Local Law Enforcement Block Grants 

MORE Making Officer Redeployment Effective 

NCHS National Center for Health Statistics 

NVCS National Crime Victimization Survey 

OJP Office of Justice Programs 

ORI originating agency identifier 

UCR Uniform Crime Reporting 

UHP Universal Hiring Program 

VCCLEA Violent Crime Control and Law Enforcement Act of 1994 

This is a work of the U.S. government and is not subject to copyright protection in the 

United States. It may be reproduced and distributed in its entirety without further 

permission from GAO. However, because this work may contain copyrighted images or 

other material, permission from the copyright holder may be necessary if you wish to 

reproduce this material separately. 
Page 1 GAO-06-104 Community Policing Grants 

October 14, 2005 

The Honorable F. James Sensenbrenner, Jr. 

Chairman 

Committee on the Judiciary 

House of Representatives 

Dear Mr. Chairman: 

Provisions of the Public Safety Partnership and Community Policing Act of 

1994, Title 1 of the Violent Crime Control and Law Enforcement Act of 

1994 (VCCLEA), authorized appropriations of $8.8 billion for fiscal years 

1995 through 2000 for grants to states and local communities to increase 

the hiring and deployment of community police officers and to promote 

nationwide the concept of community policing—an approach to policing 

that involves the cooperation of law enforcement and community 

residents in identifying and developing solutions to crime problems—as an 

effective strategy to improve public safety.1

 To administer the grants, in 

October 1994, the Attorney General created the Office of Community 

Oriented Policing Services (COPS). 

According to its Director, the COPS Office was responsible for “one of the 

greatest infusions of resources into local law enforcement in our nation’s 

history,”2

 and in a report to Congress the former Attorney General linked 

increases in COPS-funded officers to declines in crime. By the summer of 

2000, the former Attorney General reported, the COPS Office had awarded 

more than $7.6 billion in grants to more than 12,000 local law enforcement 

agencies—primarily municipal, state, and county police and sheriff’s 

departments whose officers have general arrest powers—and funded over 

105,000 community policing officers. The report claimed that the funded 

officers led to an increase in the number of police officers that was well 

above what would have been expected in the absence of the passage of 

 1

P.L. 103-322 (1994), 42 U.S.C. § 3796dd. The act contained other provisions to address 

violent crime, such as those encouraging states to increase the use of incarceration for 

violent offenders, enhancing penalties for gang crimes, and expanding the number of 

federal offenses punishable by death. 

2

Frazier, Thomas, C., “Introduction from the Director,” in Attorney General, Report to 

Congress: Office of Community Oriented Policing Services, Washington, D.C.: U.S. 

Department of Justice, 2000. 

United States Government Accountability Office

Washington, DC 20548 
Page 2 GAO-06-104 Community Policing Grants 

VCCLEA, and it cited research that showed that increased police presence 

led to reductions in crime. As evidence that these officers led to 

reductions in crime, the report showed that the average number of violent 

crimes per police department declined as the number of COPS-funded 

officers increased. 

A study funded by the COPS Office and released in 2001, which attempted 

to control for some of the other factors that could influence crime rates 

and also be correlated with the distribution of COPS funds, concluded that 

COPS grants contributed to the reduction in crime in the 1990s.3

 You 

previously asked us to review this study, and we reported that its 

methodological limitations were such that the study’s results should be 

viewed as inconclusive.4

In response to our assessment of the results of the study that we reviewed, 

you asked us to undertake an independent evaluation of the impact of 

COPS grants on the decline in crime that occurred during the 1990s. This 

report provides results from our evaluation of interrelated questions about 

COPS funds, officers, crime, and policing practices. Specifically, regarding 

COPS funds: (1) From 1994 through 2001, how were COPS obligations 

distributed among local law enforcement agencies in relation to the 

populations they served and crimes in their jurisdictions, and how much of 

the obligated amounts did agencies spend? Regarding officers and crime: 

(2) To what extent did COPS grants contribute to increases in the number 

of sworn officers and declines in crime in the nation during the 1990s? 

Regarding policing practices: (3) To what extent were COPS grants during 

the 1990s associated with police departments adopting policing practices 

that the crime literature indicates could contribute to reductions in crime? 

To address our reporting objectives, we created and analyzed a database 

consisting of 12 years of data on local law enforcement agencies for the 

years 1990 through 2001. We included data from the Department of 

Justice’s (DOJ) Office of Justice Programs (OJP) on federal law 

enforcement grant obligations and expenditures (including COPS grants); 

 3

Zhao, J., and Q., Thurman. A National Evaluation of the Effect of COPS Grants on Crime 

from 1994 to 1999. Report submitted to the Office of Community Oriented Policing 

Services, Washington, D.C.: U.S. Department of Justice, December 2001. 

4

We reported our review of this study in GAO, Technical Assessment of Zhao and 

Thurman’s 2001 Evaluation of the Effects of COPS Grants on Crime, GAO-03-867R

(Washington, D.C.: June 13, 2003). 
Page 3 GAO-06-104 Community Policing Grants 

the Federal Bureau of Investigation’s (FBI) Uniform Crime Reporting 

(UCR) Program on crime and sworn officers; the Department of 

Commerce’s Bureau of Economic Analysis on local economic conditions 

such as employment rates and per capita income; and the National Center 

for Health Statistics and U.S. Census Bureau’s estimates of demographic 

characteristics of local populations—such as their age, race, and gender 

composition. The UCR crime data that we used are data on crimes 

reported to or known by the police and reported to the UCR Program. The 

crimes in the UCR are based on the FBI’s crime index. The index crimes 

include the violent crimes of murder and non-negligent manslaughter, 

forcible rape, robbery, and aggravated assault as well as the property 

crimes of burglary, larceny-theft, motor vehicle theft, and arson. The FBI 

reports that there is limited reporting of arson offenses to the UCR 

Program by law enforcement agencies. We therefore excluded arson 

crimes from our analysis.5

Prior to developing and using the database to address our objectives, we 

assessed the reliability of each data source, and in preparing this report, 

we used only the data that we found to be sufficiently reliable for the 

purposes of our report. We also assessed possible biases in our estimates 

of the effects of COPS funds on crime arising from our use of UCR data on 

reported crimes. We concluded from our analysis that our estimates of the 

impacts of COPS funds are likely to understate the effect of COPS funds 

on crime. (See app. I for a more detailed discussion of our approach, 

methods, and database construction.) 

To describe how COPS grant funds were distributed and spent, we 

analyzed data on COPS obligations to and expenditures by local law 

enforcement agencies, comparing them with several characteristics of the 

agencies that received COPS funds, such as population size and crime 

levels. 

To assess the possible relationships between COPS expenditures and 

changes in the number of officers and rates of crime, we analyzed data on 

the agencies that reported complete crime and officer data for at least 1 

year from 1990 through 2001 using a two-stage regression model of these 

relationships. In the first stage, we estimated the relationship between the 

 5

Because of the limited reporting of arson, the FBI also excludes arson from its published 

tables containing national estimates of index crimes. See Federal Bureau of Investigation, 

Crime in the United States, Uniform Crime Reports, Washington, D.C.: U.S. Department 

of Justice, published annually. 
Page 4 GAO-06-104 Community Policing Grants 

variation in the timing and amount of agencies’ expenditures on COPS 

grants that were for hiring officers and changes in the number of officers. 

In the second stage, we estimated the relationship between changes in 

COPS expenditures and changes in crime rates using fixed-effects 

regression models. We used the results from these two sets of regressions 

to calculate the amount of the change in crime (from the second stage) 

due to changes in officers (from the first stage). As the relationship 

between officer levels and crime rates may reflect a complex causal 

relationship, we used COPS hiring grants as a statistical instrument to help 

to identify the relationship between officers and crime. In both sets of 

regression models, we used agency and year fixed effects to control for 

unobserved sources of variation among agencies (within a given year) and 

within agencies (over time). We also included variables to measure 

agencies’ pre-1994 trends in the growth of crime rates and officers. These 

controls allowed us to compare agencies that had similar, pre-COPS trends 

in these variables, thereby reducing further the differences among 

agencies that are not due to COPS expenditures. To control for economic 

factors that may be related to crime—such as employment and income—

we included measures of local economic conditions, and to control for 

changes in the composition of local populations that could be correlated 

with crime, we included measures of age and race composition of local 

populations. Finally, to control for changes in state-level practices that 

could affect crime rates, such as changes in state incarceration rates or 

state sentencing policy, we included state-by-year fixed effects in our 

regression models. (See app. VI for additional details about our regression 

models.) 

To address the relationship between COPS grants and changes in policing 

practices, we analyzed data from two surveys of nationally representative 

samples of local law enforcement agencies on policing practices that they 

reportedly implemented in various years from 1993 to 2000. The first 

survey—the Policing Strategies Survey—was administered in 1993 and 

1997 to provide information on the development and implementation of 

community policing.6

 The second survey—the National Evaluation of 

 6

The first survey was the National Survey of Community Policing Strategies, and it was 

administered in 1993 and 1997. The Police Foundation administered the 1993 wave of the 

survey, and ORC Macro International, Inc. and the Police Executive Research Forum 

administered the 1997 wave of the survey. Both surveys used the same sampling frame. In 

the remainder of this report, we refer to the two waves of this longitudinal survey as the 

Policing Strategies Survey. 
Page 5 GAO-06-104 Community Policing Grants 

COPS Survey—was administered in 1996 and 2000.7 We identified and 

analyzed practices that are associated with problem-solving, placeoriented approaches to policing, community collaboration efforts, and the 

use of crime analysis. We assessed changes in the levels of reported 

practices between agencies that spent COPS grants over particular periods 

with those that did not receive or spend COPS grant funds. To control for 

the underlying trends in reported policing practices, we estimated fixedeffects regression models of the effects of COPS grants expenditures on 

changes in reported policing practices. To assess the possible relationship 

between policing practices and crime, we analyzed systematic reviews of 

the effectiveness of policing practices in reducing crime to identify the 

types of policing practices that have been judged to be effective in 

preventing crime. (See app. VII for details about the surveys and our 

analytic methods.) 

In addition, we reviewed relevant economic and criminological literatures 

that addressed issues related to estimating models of the effects of federal 

grant funds on crime rates. We spoke with officials at the Department of 

Justice about the operation of the COPS program, and we also spoke with 

researchers about our approach and methods. We reviewed our approach 

and methods with a group of experts in the field of policing and crime. The 

group consisted of criminologists, economists, statisticians, and criminal 

justice practitioners, and was convened for us by the National Research 

Council of the National Academies to enable participants to offer their 

individual views as experts in the field. 

We conducted our work between January 2004 and August 2005 in 

accordance with generally accepted government auditing standards. 

Established in October 1994 by the Attorney General to implement the 

administration of community policing grants under VCCLEA, the Office of 

Community Oriented Policing Services announced it first grant programs 

in 1994. Prior to its establishment, in December 1993 the Department of 

 7

The second survey was the National Evaluation of the COPS Program survey, which was 

conducted by the National Opinion Research Corporation for the Urban Institute in its 

evaluation of the implementation of the COPS program. It was a nationally representative 

sample of law enforcement agencies that were contacted in 1996 and again in 2000. In the 

remainder of this letter, we refer to this second survey as the National Evaluation of COPS 

Survey. 

Background 
Page 6 GAO-06-104 Community Policing Grants 

Justice awarded community policing grants to hire officers under the 

Police Hiring Supplement.8

The COPS Office distributed grants in a variety of program funding 

categories. Hiring grants, which required agencies to hire new officers and 

at the same time to indicate the types of community policing strategies 

that they intended to implement with the grants, was the largest COPS 

grant program category in terms of the amounts of grant funds obligated.9

The hiring grants paid a maximum of $75,000 per officer over a 3-year 

period (or at most 75 percent of an officer’s salary) and generally required 

that local agencies cover the remaining salary and benefits with state or 

local funds. From 1994 through 2001, more than $4.8 billion in COPS 

obligations (or about 64 percent of COPS obligations over this period) 

were in the form of hiring grants. The Making Officer Redeployment 

Effective (MORE) grant program, which provided funds to law 

enforcement agencies to purchase equipment, hire civilians, and redeploy 

existing officers to community policing was the second largest COPS grant 

program, obligating more than $1.2 billion. Additional COPS grant 

programs provided funds for specific innovations in policing and for a 

variety of other purposes. 

Each year the COPS Office was required to distribute half of the grant 

funds to agencies in communities whose populations exceeded 150,000 

 8

The Police Hiring Supplement Program was established by the Supplemental 

Appropriations Act of 1993 (P.L. 103-50 (1993)). The grants made under this program were 

funded by DOJ’s Bureau of Justice Assistance. In this report, when we refer to COPS 

grants, we include both the grants made under the Police Hiring Supplement and the 

community policing grants authorized under VCCLEA. 

9

Hiring programs authorized under VCCLEA and administered by the COPS office included 

the Phase I program, which funded qualified applicants who had applied for the Police 

Hiring Supplement but were denied because of the limited funds available; COPS AHEAD 

(Accelerated Hiring, Education, and Deployment) for municipalities with populations of 

50,000 and above; and COPS FAST (Funding Accelerated for Smaller Towns) for towns 

with populations below 50,000. In June 1995, Phase I, COPS AHEAD, and COPS FAST were 

replaced by the Universal Hiring Program. 
Page 7 GAO-06-104 Community Policing Grants 

persons and half of the grant funds to agencies in communities with 

populations of 150,000 or fewer persons.10

In the applications for hiring grants, the COPS Office requested agencies to 

indicate the types of community policing practices that they planned to 

implement with their grants. The various practices related to community 

policing included practices such as identifying crime problems by looking 

at records of crime trends and analyzing repeat calls for service, working 

with other public agencies to solve disorder problems, locating offices or 

stations within neighborhoods, and collaborating with community 

residents by increasing officer contact with citizens and improving citizen 

feedback. These types of policing practices also corresponded with 

general approaches to policing. For example, problem-solving policing 

practices may rely on crime analysis tools to help to identify crime 

problems and develop solutions to them. Place-oriented practices attempt 

to identify locations where crime occurs repeatedly and to implement 

procedures to disrupt these recurrences of crime. By collaborating with 

community residents, agencies attempt to improve citizen feedback about 

crime problems and effectiveness of policing to address these problems. 

In 2000, DOJ reported that COPS-funded officers helped to reduce crime 

and reported that the drop in crime that occurred after 1994 was more 

than what would have been expected in the absence of the passage of 

VCCLEA and the creation of the COPS Office.11 The report suggested that 

COPS had achieved its goal of funding 100,000 officers, and through 

increases in officers and the practice of community policing, the COPS 

program was credited with reducing crime. However, while COPS may 

have funded 100,000 officers, it was not apparent that the funded officers 

had resulted in new officers having been hired. Researchers at the Urban 

Institute reported in 2000, for example, their estimates that by 2003, the 

COPS program would have raised the level of police on the street by the 

 10Of funds available in any fiscal year, up to 3 percent could have been used for technical 

assistance or for evaluations or studies carried out or commissioned by the Attorney 

General. The requirement to allocate the funds by size of agency population applies to the 

remaining funds in any fiscal year (42 U.S.C. § 3793 (a)(11)(B)). In addition, COPS had to 

meet a national coverage requirement to ensure that no state received less than 0.5 percent 

of total funding. 

11Attorney General, Report to Congress: Office of Community Oriented Policing Services, 

Washington, D.C.: U.S. Department of Justice, 2000. 
Page 8 GAO-06-104 Community Policing Grants 

equivalent of 62,700 to 83,900 full-time equivalent officers.12 They also 

indicated that it was unclear whether the program would ever increase the 

number of officers on the street at a single time by 100,000.13 

The COPS Office-funded study of the effect of COPS grants on crime in 

over 6,000 communities from 1995 through 1999 that had received COPS 

grants concluded that COPS grants were effective in reducing crime.14 The 

study also reported that COPS grants that encouraged agencies to 

implement a variety of innovative strategies to improve public safety had 

larger impacts on reducing violent and property crime than did other 

COPS grant types.15 However, a study released by the Heritage Foundation, 

which was based upon an analysis of county-level data, was unable to 

replicate the findings of the COPS Office-funded study.16 Specifically, the 

Heritage study found no effect of COPS hiring grants on crime rates, but it 

did find that the COPS grants for specific problems—such as gangs, 

domestic violence, and illegal use of firearms by youth—were associated 

with reductions in crime. In addition, we questioned whether the sizes of 

the effects of COPS grants on crime that were reported in the COPS 

Office-funded study were large enough to be significant in a practical 

sense and whether they could accurately represent the expected returns 

on the investment of billions of dollars.17

 12Roth, Jeffrey, et al., National Evaluation of the Implementation of the COPS Program, 

Washington, D.C.: National Institute of Justice, August 2000. 

13In a 2002 report, the Urban Institute researchers updated their estimates of the number of 

officers due to COPS and reported an estimate of a permanent increase of between 69,100 

and 92,200 officers post-2005, taking into account post-grant attrition of officers. Koper, 

Christopher, et al., Putting 100,000 Officers on the Street: A Survey-Based Assessment of 

the Federal COPS Program, Washington, D.C.: The Urban Institute, 2002. 

14Zhao and Thurman, 2001. 

15The authors of the COPS Office-funded study revised their report to take into account 

criticism presented by reviews, and in 2004, they released their final report on the effect of 

COPS grants on crime. In their final report, they updated their findings through 2000, and 

their results were comparable to what they reported in their initial report. Zhao, J., and Q. 

Thurman, Funding Community Policing to Reduce Crime: Have COPS Grants Made a 

Difference from 1994 to 2000? Report submitted to the Office of Community Oriented 

Policing Services, U.S. Department of Justice, July 2004. 

16Muhlhausen, D., Do Community Oriented Policing Services Grants Affect Violent Crime 

Rates (Washington, D.C.: The Heritage Foundation, May 25, 2001). 

17GAO Technical Assessment of Zhao and Thurman’s 2001 Evaluation of the Effects of 

COPS Grants on Crime, GAO-03-867R (Washington, D.C.: June 13, 2003). 
Page 9 GAO-06-104 Community Policing Grants 

Assessing the contribution of COPS funds to the decline in crime during 

the 1990s presents challenges for evaluators. Nationwide, crime rates 

began to decline in about 1991, before the COPS program announced its 

first grant programs in 1994 (fig. 1). Hence the factors other than COPS 

grants that were responsible for precipitating the decline in crime could 

have continued to influence its decline throughout the 1990s. Researchers 

have pointed to a number of factors that could have precipitated the 

decline in crime, including increased use of prison as a punishment for 

violent crimes, improved economic conditions, and the subsiding of 

violence that accompanied the expansion of drug markets. To the extent 

that any of these factors are correlated with the distribution of COPS 

grants, they could be responsible for impacts that have been attributed to 

COPS grants. 
Page 10 GAO-06-104 Community Policing Grants 

Figure 1: Total, Violent, and Property Crime Rates per 100,000 Persons, as Reported in the Uniform Crime Reports, 1970-2001 

Prior studies of the impact of COPS grants on crime have correlated COPS 

funds with crime rates, controlling for other factors that could influence 

crime rates. The authors of the prior studies describe various mechanisms 

by which COPS grants may affect crime, but their statistical models do not 

explicitly take these mechanisms into account in estimating the effects of 

the grants. By identifying and explicitly modeling mechanisms through 

1,000

2,000

3,000

4,000

5,000

6,000

7,000

0

200

400

600

800

1970 1975 1980 1985 1990 1994 2001

Calendar year

Index crime rate

Property crime rate

Source: GAO analysis of Uniform Crime Report data as reported on the Bureau of Just ice Statistics online analysis of

 Uniform Crime Report data. Prepared by the National Archive of Criminal Justice Data. Data available at

 http://.bjsdata.ojp.usdoj.gov/dataonline/

Violent crime rate

Total and property crime rates per 100,000 population Violent crime rate per 100,000 population

COPS grant period
Page 11 GAO-06-104 Community Policing Grants 

which COPS funds could affect crimes—such as increasing the number of 

sworn officers on the street who are available for patrolling places or 

contributing to changes in policing practices that may be effective in 

preventing crime—the possibility of a spurious relationship between inputs 

(such as COPS funds) and outcomes (such as crime) can be minimized. 

(For additional background information, see app. II.) 

Our analysis showed that from 1994 through 2001, COPS obligated more 

than $7.32 billion to 10,680 agencies for which we were able to link Office 

of Justice Programs financial data on COPS obligations to the records of 

law enforcement agencies.18 About $4.7 billion (or 64 percent) of these 

obligations were in the form of hiring grants. About half of these funds 

went to agencies serving populations of 150,000 or fewer persons and 

about half was distributed to agencies serving populations of more than 

150,000 persons. This distribution roughly corresponds to the distribution 

of index crimes across the two size categories of jurisdictions. However, in 

relation to violent crimes, the share of COPS funds distributed to larger 

jurisdictions was smaller than the share of violent crimes that they 

contributed to the national total. For example, agencies serving 

populations of more than 150,000 persons contributed about 58 percent of 

all violent crimes reported to the UCR during this time period while 

receiving about half of all COPS funds. To be specific, the smallest 

agencies—those serving populations of fewer than 10,000 persons—

received an average of $1,573 per violent crime reported to UCR. Agencies 

serving populations of more than 150,000 persons received about $418 in 

COPS funds per violent crime. 

By the end of 2001, the COPS grantee agencies in our sample had spent 

about $5 billion (or 68 percent of the $7.3 billion obligated to them) from 

1994 through 2001. Annually, the total amount of COPS expenditures made 

by grantees increased each year from 1994 until 2000, and then declined, 

while the number of agencies that drew down COPS funds peaked in 1998 

at about 7,600 and declined to about 6,000 in 2001. From 1994 through 

2001, a total of about 10,300 agencies spent COPS funds. The maximum 

number of agencies spending funds in any given year occurred during 

1998, when about 7,600 agencies spent funds. From 1998 through 2000, the 

amount of COPS expenditures per person in the jurisdiction served by an 

 18The amount obligated to these agencies was 96.1 percent of the $7.6 billion total in COPS 

obligations reported in the Office of Justice Programs financial data. 

Results 
Page 12 GAO-06-104 Community Policing Grants 

agency increased from about $4 to about $4.80. COPS expenditures 

amounted to an annual average of about 1 percent of total expenditures 

for police services by local law enforcement agencies from 1994 through 

2001. This contribution varied by year. For example, in 1999 and 2000, 

COPS expenditures were about 1.5 percent of total local police 

expenditures. (See app. III for a further discussion of COPS obligations 

and expenditures.) 

For the years 1994 through 2001, we infer from our estimates that COPS 

hiring grant expenditures contributed to increases in sworn officer levels 

above the levels that would have been expected without these funds. The 

additional number of sworn officers stemming from these funds varied 

over the years, and it increased from 1994 though 2000 and declined in 

2001 (fig. 2). For example, for 1997 we estimate that COPS funds 

contributed about 14,000 additional officers in that year—or about 2.4 

percent of the total number of sworn officers nationwide—and for 2000, 

COPS funds contributed about 17,000 additional officers—or about 3 

percent of the total number of sworn officers nationwide. For all years 

from 1994 through 2001, we estimate that COPS expenditures paid for a 

total of about 88,000 additional officer-years over this entire period, where 

the total number of officer-years equals the sum of the number of officers 

due to COPS grant expenditures in each year. An officer-year refers to the 

number of officers in a given year that we could attribute to COPS 

expenditures, and the additional officers in a given year attributable to 

COPS expenditures represent a net addition to the stock of sworn 

officers.19 Using the results from our regression estimates of the effects of 

COPS expenditures on the level of sworn officers, we set the values for 

COPS expenditures to zero to predict the level of officers absent COPS 

funds. The difference between this number and the actual number of 

sworn officers yields the number of officers due to COPS expenditures. 

Our analysis also shows that apart from the COPS hiring and COPS MORE 

grants, other COPS grant types did not have a significant effect on officer 

strength. (See app. IV for more detailed information about the results of 

our analysis of COPS expenditures on officers.) 

 19An officer-year is not equivalent to the total number of officers or full-time officer 

equivalents hired as a result of COPS funds; nor is it equivalent to the total number of 

officers funded by COPS grants. Across years, the COPS funds may have paid for the same 

person. In counting officer-years, this person would be counted one time for each year in 

which we estimated that COPS funds paid for the position. 
Page 13 GAO-06-104 Community Policing Grants 

Figure 2: Estimated Effects of COPS Grant Expenditures on the Number of Sworn 

Officers, 1991-2001 

We estimate that the COPS grant expenditures contributed to the 

reduction in crime in the 1990s independently of other factors that we 

were able to take into account in our analysis. Other factors that could 

have contributed to the reduction in crimes in the 1990s that we took into 

account included federal law enforcement expenditures other than COPS 

grants, local economic conditions and changes in population composition, 

and changes in state-level policies and practices that could be correlated 

with crime, such as incarceration and sentencing policy. Specifically, from 

our model of the effect of changes in sworn officers on crime, we estimate 

that a 1 percent increase in the number of sworn officers per capita would 

lead to a 0.4 percent reduction in the total number of index crimes. 

Through their effects on changes in officers in a given year, COPS 

expenditures led to varying amounts of declines in crime rates over the 

years from 1994 through 2001. For example, the 2.4 percent increase in 

sworn officers due to COPS expenditures in 1997 was responsible for 

about a 1.1 percent decline in the total index crime rate from 1993 to 1997, 

while the roughly 3 percent increase in officers due to COPS expenditures 

Actual number of sworn officers

Predicted number of sworn officers per capita in the absence of COPS grant expenditures 

(if COPS grant expenditures were equal to zero)

Source: GAO analysis of Uniform Crime Report, Office of Justice Programs, National Center for Health Statistics, U.S. Census Bureau, 

 and Bureau of Economic Analysis data.

Estimated number of officers

Pre-COPS program period COPS program period

480,000

500,000

520,000

540,000

560,000

580,000

600,000

620,000

1991 1992 1993 1998 1994 1995 1996 1997 2001 1999 2000

Calendar year
Page 14 GAO-06-104 Community Policing Grants 

in 2000 was responsible for about 1.3 percent decline in the total index 

crime rate from 1993 to 2000. Put into another context, the total crime 

rate declined from 5,904 per 100,000 persons in 1993 to 4,367 per 100,000 

persons in 2000, or by about 26 percent. Of this 26 percent drop, we 

attribute about 5 percent to the effect of COPS. From our analysis of 

violent crimes, we estimated that declines in the violent crime rate due to 

COPS expenditures also varied with the level of officers due to COPS 

funds. The declines in violent crime rates attributable to COPS increased 

from about 2 percent in 1997 to 2.5 percent in 2000, where both of the 

amounts of decline attributable to COPS expenditures are based upon 

comparisons with the 1993 violent crime rate (fig. 3). We further estimate 

that at its peak in 1998, COPS accounted for about a 1.2 percent decline in 

the property crime rate. 

Figure 3: Annual Percentage Changes in the Violent Crime Rate from 1993: Total 

Change and Estimated Change Due to COPS Grants 

Our estimates of the impacts of COPS expenditures on the broad 

categories of crime are supported by our findings from our crime-typespecific regression models. We find significant reductions due to COPS 

expenditures for the crimes of murder and non-negligent manslaughter, 

robbery, aggravated assault, burglary, and motor vehicle theft. Our 

analysis of larceny indicates that while the relationship between COPS 

Estimated percentage change in violent crime rates due to COPS grants

Total percentage change in violent crime rates from 1993

Source: GAO analysis of Uniform Crime Report, Office of Justice Programs, National Center for Health Statistics, U.S. Census Bureau, 

 and Bureau of Economic Analysis data.

1994 1995 1996 1997 1998 1999 2000 2001

Calendar year

-35

-30

-25

-20

-15

-10

-5

0

Percent change in violent crime rate since 1993
Page 15 GAO-06-104 Community Policing Grants 

funds and larceny is a negative one, it is not statistically significant, nor is 

the effect of COPS on rape statistically significant. Further, we estimated 

the effects of COPS grants on the total crime rate under various 

assumptions about lags between the receipt of COPS grants and 

expenditures of COPS funds. The estimates for the amount of the decline 

in the total crime rate that we report here—for example, the 1.3 percent of 

the decline in crime from 1993 to 2000—are among the smallest effects 

that we estimated from our various models. Under different assumptions 

about lags associated with COPS expenditures, the amount attributable to 

COPS could be as high as 3.2 percent. Interestingly, the 1.3 percent 

decline in the index crime rate that we attribute to COPS expenditures in 

2000 is on the same order of magnitude as the contribution of COPS 

expenditures to total local spending on police. In 2000, for example, COPS 

expenditures accounted for about 1.5 percent of total local police 

expenditures. We further find that factors other than COPS expenditures 

account for the majority of the decline in the crime rate. (See app. IV for 

more detailed information about the results of our analysis of COPS 

expenditures on crime.) 

Our regression analysis of the Policing Strategies Survey data for 1993 and 

1997 indicate that receipt of a COPS grant and the amount of per capita 

COPS expenditures by agencies were associated with increases in the 

agencies’ reported use of problem-solving and place-oriented policing 

practices but not crime analysis and community collaboration policing 

practices (fig.4). According to our review studies of the effectiveness of 

policing practices, problem-solving and place-oriented practices are 

among those that the crime literature indicates may be effective in 

reducing crime. With problem-solving practices, police focus on specific 

problems and tailor their strategies to them. Place-oriented practices 

include efforts to identify the locations where crime repeatedly occurs and 

to implement procedures to disrupt these recurrences of crime. Crime 

analysis includes the use of tools such as geographic information systems 

to identify crime patterns. Community collaboration includes attempts to 

improve or enhance citizen feedback about crime problems and the 

effectiveness of policing efforts to address them. In our regressions, we 

controlled for the underlying trends in the reported adoption of policing 

practices, agency characteristics, and local economic conditions. 
Page 16 GAO-06-104 Community Policing Grants 

Figure 4: Reported Levels of Policing Practices in 1993 and 1997 in Agencies That 

Did and Did Not Receive COPS Grants, by Category of Policing Practice 

Our analysis of the National Evaluation of COPS Survey—which measured 

practices in 1996 and again in 2000—showed that while COPS grantee 

agencies increased their reported use of all policing practices combined, 

these changes were not statistically significant in regressions that 

controlled for the underlying trends in the reported adoption of policing 

practices, agency characteristics, and local economic conditions. (See app. 

V for more detailed information about the results of our analysis of COPS 

expenditures and policing practices.) 

While we find that COPS expenditures led to increases in sworn police 

officers above levels that would have been expected without these 

expenditures and through the increases in sworn officers led to declines in 

crime, we conclude that COPS grants were not the major cause of the 

decline in crime from 1994 through 2001. Other factors—which other 

researchers have attempted to sort out—combined to contribute more to 

the reduction in crime than did COPS expenditures. This is not surprising, 

as COPS expenditures—while a large federal investment in local law 

enforcement—made a comparatively small contribution to local law 

enforcement expenditures for policing. 

Nevertheless, our analysis shows that COPS grant expenditures did reduce 

crime during the 1990s. Our models isolate the effects of COPS 

Concluding 

Observations 

Problem-solving: COPS grantee

Problem-solving: Non-COPS agency

Source: GAO analysis of Policing Strategies Survey and Office of Justice Programs financial data.

Place-oriented: COPS grantee

Place-oriented: Non-COPS agency

Mean number of policing practices

1993 1997

Calendar year

0

1

2

3

4

5

6

7
Page 17 GAO-06-104 Community Policing Grants 

expenditures from the effects of other factors. We cannot identify another 

variable that is correlated with changes in COPS expenditures, officers, 

and crime rates in local communities that would explain away our 

findings. Thus, we conclude that the results of our model are sound. 

Further, our results do not address whether the COPS program met its 

goals of putting 100,000 officers on the street—and the evidence suggests 

that while it funded more than 100,000 officers, it may have fallen short of 

achieving this goal. Still, through the increases in officers that we attribute 

to COPS expenditures, we find that COPS grants affected crime rates. 

Therefore, as a demonstration of whether a federal program can affect 

crime through hiring officers and changing policing practices, the evidence 

indicates that COPS contributed to declines in crime above the levels of 

declines that would have been expected without it. 

Our work cannot identify an optimum number of officers needed by any 

individual agency to maximize the effect of officers on reducing crime, nor 

can it identify the specific types of practices that agencies should adopt in 

particular settings. It is highly likely that there is indeed a point where 

additional officers no longer affect crime. The numbers of additional 

officers hired as a result of COPS were relatively small compared with the 

sizes of individual police agencies, and these small increases led to 

commensurate reductions in crime rates. Given resource constraints and 

competing priorities at all levels of government, it is probably unlikely that 

most police agencies would have the resources available to hire large 

enough numbers of officers to go past the point of diminishing returns. 

We provided a draft of this report to the Attorney General for comment on 

September 13, 2005. In its written comments, the Office of Community 

Oriented Policing Services (COPS) drew upon information from both this 

report and our prior correspondence on the effects of COPS grants on 

crime. They said that we were careful and diligent in our research, and 

that our findings support conclusions reached by others and correspond 

with what local law enforcement leaders report. The COPS Office also 

expanded upon some of our main findings, which they characterized 

correctly. In their comments, the COPS Office introduced data and 

opinions about potential effects of the COPS grants that were beyond the 

scope of our work. We therefore cannot corroborate these statements. 

For example, in discussing our findings about the effects of COPS grants 

on sworn officers, the COPS Office introduced data about officers derived 

from the MORE technology grants and reports that 42,058 (or 36 percent) 

of the 118,397 officers that the COPS Office has funded to date are derived 

Agency Comments 

and Our Evaluation 
Page 18 GAO-06-104 Community Policing Grants 

from the MORE grants. Our work does not corroborate either of these 

figures. We point out in Appendix VI that our estimates of a total of 88,000 

additional officer-years takes into account the effects of MORE grant 

expenditures. 

In their comments on our finding about changes in policing practices that 

resulted from COPS, the COPS Office points out that the aggregate counts 

of policing practices that we used in our analysis provide only a superficial 

measure of the level of community policing taking place. We 

acknowledged this point in appendix VII, but chose not to speculate on the 

extent to which police departments increased the amount of problem 

solving or other policing practices they engaged in. By speculating that 

agencies may have increased the quantity of a specific activity, the COPS 

Office provides only one view of what may have happened. Another view, 

proffered by policing researchers, is that there is little evidence to suggest 

that problem-solving policing was implemented with sufficient rigor in 

enough departments to have contributed to declines in violent crime 

during the 1990s. As they point out, problem-solving activities may have 

increased, and they may have contributed to declines in crime, “but we 

simply do not know.”20

We are sending copies of this report to other interested congressional 

committees and the Attorney General. We will also make copies available 

to others upon request. In addition, the report will be available at no 

charge on GAO’s Web site at http://www.gao.gov. 

If you or your staff have any questions concerning this report, please 

contact Laurie Ekstrand at (202) 512-8777 or by e-mail at 

Ekstrandl@gao.gov or Nancy Kingsbury at (202) 512-2700 or by e-mail at 

 20Eck, John, and Edward Maguire, “Have Changes in Policing Reduced Violent Crime? An 

Assessment of the Evidence.” In Blumstein, Alfred, and Joel Wallman (eds.), The Crime 

Drop in America, Cambridge: Cambridge University Press, 2000: p. 245. 
Page 19 GAO-06-104 Community Policing Grants 

Kingsburyn@gao.gov. Contact points for our Offices of Congressional 

Relations and Public Affairs may be found on the last page of this report. 

Key contributors to this report are listed in appendix IX. 

Sincerely yours, 

Laurie E. Ekstrand, Director 

Homeland Security and Justice Issues 

Nancy R. Kingsbury, Managing Director 

Applied Research and Methods 
Appendix I: Objectives, Scope, and 

Methodology 

Page 20 GAO-06-104 Community Policing Grants 

In response to a request from F. James Sensenbrenner, Jr., Chairman, 

Committee on the Judiciary, House of Representatives, this report 

provides the findings of our evaluation of the impact of Community 

Oriented Policing Services (COPS) grants on the decline in crime that 

occurred during the 1990s. Our objectives were to address interrelated 

questions about COPS funds, officers, crime, and policing practices. 

Specifically, regarding COPS funds: (1) From 1994 through 2001, how were 

COPS obligations distributed among local law enforcement agencies in 

relation to the populations they served and crimes in their jurisdictions, 

and how much of the obligated amounts did agencies spend? Regarding 

officers and crime: (2) To what extent did COPS grants contribute to 

increases in the number of sworn officers and declines in crime in the 

nation during the 1990s? Regarding policing practices: (3) To what extent 

were COPS grants during the 1990s associated with police departments 

adopting policing practices that the crime literature indicates could 

contribute to reductions in crime? 

To address our reporting objectives, we analyzed a database consisting of 

12 years of data from 1990 through 2001 on local law enforcement 

agencies. To create this database—our primary analysis database—we 

obtained data from several sources, and we organized the data as a panel 

dataset in that it contained information on multiple law enforcement 

agencies over multiple years. For each agency, we obtained data on COPS 

and other federal law enforcement grant obligations and expenditures 

from the Department of Justice’s (DOJ) Office of Justice Programs (OJP), 

and data on index crimes and the number of sworn officers from the 

Federal Bureau of Investigation’s (FBI) Uniform Crime Reporting (UCR) 

Program. Index crimes include the violent crimes of murder and nonnegligent manslaughter, forcible rape, robbery, and aggravated assault, as 

well as the property crimes of burglary, larceny-theft, motor vehicle theft, 

and arson.1

 As shown in table 1, in 2002, property crimes constituted 88 

percent of the 11,877,218 index crimes. Among violent crimes, robberies 

accounted for 3.5 percent of all index crimes, and aggravated assaults 

accounted for 7.5 percent. 

 1

We excluded arson from our analyses because according to the FBI, there is limited 

reporting of arson offenses to the UCR Program by law enforcement agencies. Also 

because of the limited reporting of arson by law enforcement agencies, the FBI does not 

include estimates for arson in its published tables that contain offense estimates, including 

its table 1, which reports its estimates of index crimes for the nation as a whole. 

Appendix I: Objectives, Scope, and 

Methodology 

Overview of Our 

Approach and 

Methodology 
Appendix I: Objectives, Scope, and 

Methodology 

Page 21 GAO-06-104 Community Policing Grants 

Table 1: Index of Crimes, 2002, as Reported by the FBI, Excluding Arson 

Crime category Number

Percentage of 

index crimesa

Index crimesb11,877,218 100.0%

 Violent crimesc 1,426,325 12.0%

 Murder and non-negligent manslaughter 16,204 0.1%

 Forcible rape 95,136 0.8%

 Robbery 420,637 3.5%

 Aggravated assault 894,348 7.5%

 Property crimesd 10,450,893 88.0%

 Burglary 2,151,875 18.1%

 Larceny theft 7,052,922 59.4%

 Motor vehicle theft 1,246,096 10.5%

Source: Table 1 of Federal Bureau of Investigation, Crime in the United States, 2002, Uniform Crime Reports, Washington, D.C.: 

Department of Justice. Printed annually. 

Note: Although arson is part of the crime index, the FBI does not estimate the number of arson crimes 

for the nation as a whole, and consequently, it does not include an estimate for arson crimes in its 

table 1 of Crime in the United States. 

a

Percentages for specific types of crime within a category may not add up to category totals because 

of rounding. 

b

Sum of violent and property crimes. 

c

Sum of murder and non-negligent manslaughter, forcible rape, robbery, and aggravated assault. 

d

Sum of burglary, larceny theft, and motor vehicle theft. 

We obtained data on some of the factors that the research literature on 

crime suggests are related to changes in crime. From the Department of 

Commerce’s Bureau of Economic Analysis, we obtained data on local 

economic conditions—including employment rates and per capita 

income—and from the National Center for Health Statistics and the U.S. 

Census Bureau—we obtained data on demographic variables—including 

the percentage of the population aged 15 to 24, and the racial and gender 

composition of the population. 

We also analyzed data from two surveys of nationally representative 

samples of police departments on the policing practices that they 

reportedly implemented in various years from 1993 to 2000. We refer to the 

first survey as the Policing Strategies Survey, and it was administered in 
Appendix I: Objectives, Scope, and 

Methodology 

Page 22 GAO-06-104 Community Policing Grants 

1993 and again in 1997.2 We refer to the second survey as the National 

Evaluation of COPS Survey, as it was completed as part of the Urban 

Institute’s national evaluation of the implementation of the COPS program, 

and we used the data from the surveys that were administered in 1996 and 

2000. 3

 The multiple administrations of each survey allowed us to analyze 

changes in policing practices. Using agency and year identifiers, we 

matched and merged data from our primary analysis database with the 

agency-level records in each of the surveys. 

Prior to developing and analyzing our database, we assessed the reliability 

of each data source, and in preparing this report, we used only the data 

that we found to be sufficiently reliable for the purposes of our report. 

In addition, to identify policing practices that are considered to be 

effective in preventing crime, we analyzed reviews of research and 

evaluation literature. We also reviewed relevant economic and 

criminological literatures that addressed issues related to estimating 

models of the effects of federal grant funds on crime rates. We spoke with 

officials at the Department of Justice about the operation of the COPS 

programs, and we also spoke with researchers about our approach and 

methods. We reviewed our approach and methods with a group of experts 

in the field of policing and crime. The group consisted of criminologists, 

economists, statisticians, and criminal justice practitioners, and was 

convened for us by the National Research Council of the National 

Academies to enable participants to offer their individual views as experts 

in the field. 

We conducted our work between January 2004 and August 2005 in 

accordance with generally accepted government auditing standards. 

 2

Rosenthal, Arlen M., and Lorie Fridell. National Survey of Community Policing 

Strategies Update, 1997, and Modified 1992-1993 Data [Computer file]. Inter-university 

Consortium for Political and Social Research (ICPSR) version. Calverton, Maryland: ORC 

Macro International, Inc. [producer], 2002. Ann Arbor, Michigan: ICPSR [distributor], 2002. 

In the remainder of this report, we refer to the two administrations of this longitudinal 

survey as the Policing Strategies Survey. 

3

The second survey was conducted by the National Opinion Research Center for the Urban 

Institute in 1996 and 2000 as part of the National Institute of Justice-funded implementation 

evaluation of the COPS program. See Roth, J., et al., National Evaluation of the COPS 

Program—Title I of the 1994 Crime Act, Washington, D.C.: National Institute of Justice, 

August 2000. In the remainder of this report, we refer to the two administrations of this 

second longitudinal survey as the National Evaluation of COPS Survey. 
Appendix I: Objectives, Scope, and 

Methodology 

Page 23 GAO-06-104 Community Policing Grants 

To address our first objective, we analyzed OJP financial system data on 

grant obligations and expenditures and UCR data on the size of 

populations served by agencies and crimes occurring within the 

jurisdictions of the agencies that reported crime to the UCR. We used the 

OJP financial data to compute the amount of COPS funds obligated by 

COPS grants and the amount expended by local police agencies during the 

period from 1994 through 2001. To describe the overall COPS funding 

trends by grant type, we analyzed the universe of agencies in the OJP data 

that received any federal law enforcement grant during the period from 

1990 through 2001, regardless of whether or not the agency received a 

COPS grant during the period and regardless of whether we were able to 

link the data from these agencies to records in the UCR. For the years 

from 1990 through 2001, the OJP data show that 13,332 agencies received 

any federal law enforcement grant. For analyses of COPS funds by agency 

population sizes and for comparisons of funding levels with levels of 

violent and total index crime, we limited our analysis to the sample of 

agencies whose crime and population data we were able to link to the OJP 

data. This resulted in a sample of 11,187 agencies in our primary analysis 

database. These 11,187 agencies accounted for 86 percent of the reported 

crimes in the UCR data that we received from the FBI. 

The COPS Office distributed grants in a variety of programs. To describe 

the amounts of COPS obligations and expenditures, we organized the 

COPS grant programs into four broader categories of grants, and we 

reported our results at the level of these broader categories. These four 

categories include: Hiring, Making Officer Redeployment Effective 

(MORE), Innovative, and Miscellaneous grants, and the specific grant 

programs within each category, along with obligated amounts from 1994 

through 2001 for each grant program and category, are shown in table 2. 

Methods Used to Address 

the Flow of Funds 

Reporting Objective 
Appendix I: Objectives, Scope, and 

Methodology 

Page 24 GAO-06-104 Community Policing Grants 

Table 2: COPS Obligations, 1994 through 2001, by COPS Grant Categories and 

Types of Grant Programs 

 Obligations 

COPS grant category and 

types of grant programs 

Amount

(in billions 

of dollars)

Percentage

of total

Total, all grant programs $7.616 100.0%

Hiring grant programs $4.863 63.9%

Police Hiring Supplement $0.143 1.9%

COPS Phase I $0.184 2.4%

AHEAD $1.245 16.4%

FAST $1.234 16.2%

Universal Hiring Program $2.055 27.0%

MORE grants $1.262 16.6%

Innovative grant programs $0.418 5.5%

 Advancing Community Policing $0.034 0.5%

 COPS 311 $0.005 0.1%

 Distressed Neighborhoods Pilot Program $0.112 1.5%

 Community Policing to Combat Domestic 

Violence $0.070 0.9%

 Anti-Gang Initiatives $0.011 0.1%

 Integrity Initiative $0.018 0.2%

 Methamphetamine Initiative $0.089 1.2%

 Problem Solving Partnerships $0.038 0.5%

 School-Based Partnership Programs $0.031 0.4%

 Youth Firearm Violence Initiative $0.009 0.1%

Miscellaneous grants programs $1.073 14.1%

 COPS in Schools $0.533 7.0%

 Demonstration Sites Program $0.005 0.1%

 Miscellaneous $0.132 1.7%

 Technology Grants $0.207 2.7%

 Regional Community Policing Initiative $0.084 1.1%

 Small Community Grant Program $0.013 0.2%

 Tribal Grant Program $0.098 1.3%

Source: GAO analysis of Office of Justice Programs financial data. 

In our analysis, we compared the distribution of COPS obligations with the 

distribution of crimes contributed by agencies serving populations of 
Appendix I: Objectives, Scope, and 

Methodology 

Page 25 GAO-06-104 Community Policing Grants 

150,000 or fewer persons and those serving more than 150,000 persons. We 

used UCR population to identify agency size and crimes. The UCR 

population may not reflect the population that agencies provided on the 

applications for COPS grants. Our analysis of the distribution of COPS 

funds describes the extent to which the distribution of funds is related to 

agency size—as measured by populations served—and the distribution of 

violent crimes. 

To assess the effects of COPS expenditures on the number of sworn 

officers and crime, we developed and estimated a two-stage regression 

model of these relationships. In the first stage, we estimated the 

relationship between per capita COPS expenditures and per capita sworn 

officer rates in the agencies included in our sample. The per capita 

measures were based upon the UCR population for the jurisdiction 

covered by an agency. In the second stage, we estimated the relationship 

between changes in per capita COPS expenditures and changes in crime 

rates per 100,000 persons. As the relationship between officer levels and 

crime rates may reflect a complex and interrelated causal relationship, we 

used COPS hiring grants as an instrument to help to identify the 

relationship between officers and crime. To use COPS hiring grant 

expenditures as an instrument for sworn officers, we made use of the fact 

that, unlike the purposes of other COPS grant types, the purpose of hiring 

grants was limited to hiring officers. Given the number of officers, 

variation in hiring grant expenditures should be uncorrelated with other 

changes in crime. From our regression results, we calculated the elasticity 

of crime with respect to officers or the effect of a 1 percent change in the 

levels of officers on the percentage change in crime. To assess the 

robustness of our results, we estimated several specifications of our crime 

rate regression and calculated the elasticities of crime with respect to 

officers for each specification. We estimated these equations separately 

for each type of index crime. We compared the range of our estimated 

elasticities with those in the published literature on officers and crime. To 

estimate COPS’ contribution to the national decline in crime, we projected 

our sample results to the nation as a whole by weighting our results by the 

ratio of the total population in the United States to the population in the 

sample of agencies included in our analysis. 

In our regression models of the effects of COPS grant expenditures on 

officers and crime, we organized our primary analysis database as a panel 

dataset, and we limited our analysis to the 4,509 law enforcement agencies 

serving populations of 10,000 or more persons and that reported complete 

crime data for at least 1 year from 1990 through 2001. The number of 

Methods Used to Address 

the Effects of COPS 

Expenditures on Officers 

and Crime 
Appendix I: Objectives, Scope, and 

Methodology 

Page 26 GAO-06-104 Community Policing Grants 

agencies that reported complete crime data and served populations of 

10,000 or more persons varied over time, as in 1990 about 23 percent of all 

agencies in the UCR data that we received from the FBI met these criteria, 

and in 2001 about 21 percent did. However, these agencies also reported 

the majority of crimes to the UCR. From 1990 through 2001, these 

agencies reported between 86.8 percent and 88.8 percent of all index 

crimes in the UCR data that we received from the FBI. Because of data 

concerns with agencies serving populations of fewer than 10,000 persons, 

we omitted these agencies from our analysis. 

We used fixed-effects regression models to estimate the relationships 

among COPS expenditures, officers, and crime. Given that we included 

agencies based on the completeness of their crime data in each year, and 

agencies provided complete crime data in different numbers of years over 

our 1990 through 2001 analysis period, our models used an unbalanced 

panel approach. In all of our models, we expressed expenditures, officers, 

and crime in per capita amounts. The fixed-effects models provide 

estimates of the amount of change in our dependent variables—the per 

capita sworn officer rate and the per capita crime rates—that can be 

attributed to changes in the per capita COPS hiring grant expenditures, 

controlling for other factors that could also contribute to changes in the 

per capita sworn officer rate. Our models included agency and year fixed 

effects to control for unobserved differences between agencies and 

changes over time within agencies in factors that could contribute to 

declines in crime. We introduced state-by-year fixed effects into our 

regressions to control for factors occurring at the state level—such as 

changes in incarceration or state sentencing practices—that could affect 

crime rates. Further, we included in our models variables that classify 

each agency in categories based upon their pre-1994 trends in the growth 

of officers and crime. These growth cell variables allow us to make 

comparisons between agencies that were similar in their pre-COPS 

program trends but that varied in the timing and amount of COPS 

expenditures. Finally, we included in our models measures of other 

federal law enforcement grant programs that also provided funds to state 

and local law enforcement agencies for hiring officers and other crimeprevention purposes. Specifically, we included measures of the per capita 

expenditures on Local Law Enforcement Block Grants,4

 which local 

governments could use to hire law enforcement officers, pay overtime, 

 4

Local Law Enforcement Block Grant Program (LLEBG), as authorized by the Omnibus 

Consolidated Rescissions and Appropriations Act of 1996. (P.L. 104-134.) 
Appendix I: Objectives, Scope, and 

Methodology 

Page 27 GAO-06-104 Community Policing Grants 

purchase equipment, as well as several other purposes. Because of data 

limitations, we were unable to track amounts of the Edward Byrne 

Memorial State and Local Law Enforcement Assistance (Byrne Formula 

Grant Program) 5 grants that went to local agencies. Byrne Formula Grant 

funds could be used to provide for personnel, equipment, training, 

technical assistance, and information systems, among other purposes. In 

addition to the formula grant program, there was also a Byrne 

discretionary grant program, and we included measures for these grants. 

In appendix VI, we provide the details about the specific models that we 

estimated and our methods for calculating elasticities of the relationship 

between changes in officers and changes in crime rates. 

To assess whether COPS funds contributed to changes in policing 

practices, we analyzed data from the Policing Strategies and National 

Evaluation of COPS surveys, two nationally representative surveys of local 

law enforcement agencies that asked about the types of policing practices 

that the agencies reported implementing in various years. In each survey, 

chief executives or their designees were presented a list of policing 

practices and asked to indicate whether their agency implemented the 

practice. We classified items in the surveys into four categories of policing 

practices corresponding to general approaches to policing identified in the 

criminal justice literature: problem-solving practices, place-oriented 

practices, community collaboration activities, and crime analysis 

activities. Problem-solving practices call for police to focus on specific 

problems and tailor their strategies to the identified problems. Placeoriented practices include attempts to identify the locations where crime 

occurs repeatedly and to implement procedures to disrupt these 

recurrences of crime. Community collaboration practices include 

improving citizen feedback about crime problems and the effectiveness of 

policing efforts to address these problems. Crime analysis includes the use 

of tools such as geographic information systems to identify crime patterns. 

These tools may help an agency support other practices for preventing 

crime, such as problem-solving and place-oriented practices. 

 5

42 U.S.C. § 3750 et seq. The Byrne Formula Grant Program was a variable pass-through 

grant program administered by the Bureau of Justice Assistance. States were required to 

pass through to local jurisdictions amounts of funding based upon a variable pass-through 

formula. 

Methods to Assess 

Changes in Policing 

Practices 
Appendix I: Objectives, Scope, and 

Methodology 

Page 28 GAO-06-104 Community Policing Grants 

For each agency in a survey, we created a summary index of the number 

of such practices that agencies reportedly implemented in the years in 

which the surveys were administered. We then compared mean levels of 

reported practices between groups of agencies that participated in the 

COPS program and those that did not participate in the program. 

We used the data from the Policing Strategies Survey to make pre- and 

within-COPS program comparisons of changes in reported policing 

practices in 1993 and in 1997. Levels of reported practices among agencies 

that received COPS grants were compared with levels among agencies that 

were not funded by COPS grants over this period. We used the National 

Evaluation of COPS Survey to compare levels of practices in 1996 and 

2000 between groups of agencies that received COPS grants and those 

agencies that were not funded by COPS over this period. In appendix VII, 

we provide additional details about the surveys and our methods for 

analyzing the survey data. 

To assess changes in reported practices in relation to participation in the 

COPS program, we estimated separate regression models of the effects of 

the receipt of a COPS grant and per capita COPS expenditures on changes 

in reported policing practices, controlling for various characteristics of 

agencies and underlying trends in the reported adoption of policing 

practices. 

To identify policing practices that may be effective in reducing crime, we 

analyzed six studies that provided summaries of research on the 

effectiveness of policing practices and activities on reducing crime. We 

chose to review studies that reviewed research, rather than reviewing all 

of the original studies themselves, because of the volume of studies that 

have been conducted on the effectiveness of policing practices. (See app. 

VII for a list of the studies that we reviewed and additional details on 

policing practices and crime.) 
Appendix I: Objectives, Scope, and 

Methodology 

Page 29 GAO-06-104 Community Policing Grants 

To construct our primary analysis database, which consisted of 12 years of 

data from 1990 through 2001 for law enforcement agencies that reported at 

least 1 complete year of crime data to the FBI’s Uniform Crime Reporting 

Program, we obtained data from several sources and merge-matched 

information from these various sources to the level of the local law 

enforcement agency. The sources of data that we used to compile the 

annual observations from 1990 through 2001 on local police departments 

included: 

• Office of Justice Programs Financial Data—Annual data on the 

obligation and expenditures on each grant awarded by OJP. Obligations 

refer to the funds that are expected to be paid on a grant, and 

expenditures refer to the grant funds that have been paid to a recipient. 

Because OJP and the COPS Office share data on awards, the OJP data 

also included COPS grant obligation and expenditure amounts. We 

used data on grant obligation amounts to and annual amounts 

expended by each recipient of a community-oriented policing (or 

COPS) grant,6

 and annual amounts of other federal local law 

enforcement grants expended both by agencies that received COPS 

funds and those that did not. We used information about place codes 

and OJP vendors to link these data to our other sources. 

• The UCR—Annual data files on the number of crimes and sworn 

officers reported by each agency to the UCR. The data on sworn 

officers represent the reported number of full-time officers in each 

agency on October 31 of each year. We analyzed the number of sworn 

officers per 10,000 persons in the covered jurisdiction. We analyzed 

data on the violent crimes of murder and non-negligent manslaughter, 

forcible rape, robbery, and aggravated assault, and the property crimes 

of burglary, larceny-theft, and motor vehicle theft. We analyzed the 

crime rate per 100,000 persons in the covered jurisdiction for each type 

of crime, as well as the rates for all index crimes, violent crimes, and 

property crimes. We used the originating agency identifier (ORI) 

variable and place codes to link crime and officer data to other data 

sources.7

 6

In this report, COPS grants refer both to DOJ grants awarded through the Police Hiring 

Supplement Program and the COPS Office’s community policing grants authorized under 

the Violent Crime Control and Law Enforcement Act of 1994. 

7

We used Federal Information Processing Standards codes (or FIPS codes), which identify 

named population places and are issued by the National Institute of Standards and 

Technology. 

Database 

Construction and 

Samples Used in Our 

Analyses 
Appendix I: Objectives, Scope, and 

Methodology 

Page 30 GAO-06-104 Community Policing Grants 

• Bureau of Economic Analysis (U.S. Department of Commerce)—

Annual county-level estimates of per capita income and employment 

for each year from 1990 through 2001. We included in our analysis of 

officers, crime, and policing practices, measures of economic factors 

that are related to crime, such as the employment-to-population ratio 

and per capita income. We linked these data to agency-level data using 

place codes. Local economic conditions within each county are applied 

to each agency within a county. 

• National Center for Health Statistics (NCHS) and U.S. Census Bureau—

Annual estimates of the United States resident population for each 

county from 1990 through 2001. Data obtained include population 

totals and population breakdowns by gender, race, and age. Under a 

collaborative arrangement with the U.S. Census Bureau and with 

support from the National Cancer Institute, NCHS prepared postcensal 

population estimates for 2000 through 2001. The Census estimates of 

county population from 1990 through 1999 are updated to take into 

account these postcensal estimates. We included in our analysis of 

officers, crime, and policing practices measures of demographic factors 

that are related to crime, such as the percentage of total population in 

the 15-to-24 age group—an age group associated with high crime 

rates—and the racial composition of populations. We linked these data 

to agency-level data using place codes. 

• Law Enforcement Agency Identifiers Crosswalk (Bureau of Justice 

Statistics)—The crosswalk file provides geographic and other 

identification information for each record included in either the 

Federal Bureau of Investigation’s Uniform Crime Reporting Program 

files or in the Bureau of Justice Statistics (BJS) Directory of Law 

Enforcement Agencies (DLEA). The main variables each record 

contains are the UCR originating agency identifier number, agency 

name, mailing address, Census Bureau’s government identification 

number, and Federal Information Processing Standards (FIPS) state, 

county, and place codes. We utilized FIPS codes to merge records from 

the crosswalk with OJP financial data and then used agency ORI codes 

to merge the crosswalk and financial data with crime data from the 

UCR. 

To report on COPS obligations and expenditures, we first analyzed the 

amounts reported in OJP financial data before we merged the financial 

information onto the agency-level crime records in the UCR. In the OJP 

data, each record represents either an obligation or an expenditure 

amount, and an agency appears in the database each time it has either an 

Data Used in Our Analysis 

of Obligations and 

Expenditures 
Appendix I: Objectives, Scope, and 

Methodology 

Page 31 GAO-06-104 Community Policing Grants 

obligation or an expenditure. The total amount of obligations for COPS 

grants for the 1990- through 2001- period in the OJP data was $7.62 billion. 

Second, we linked the OJP financial data to agency information in the BJS 

crosswalk file. We used agency identifying information in the OJP financial 

data—such as FIPS state, county, and place codes—to link OJP records 

with agencies in the crosswalk file. This resulted in our identifying 13,332 

agencies that had at least one record of an obligation in the OJP financial 

data. Of these, 10,680 (or 80 percent) received at least one COPS grant, 

and among the agencies that received COPS grants, the total amount of 

COPS obligations was $7.32 billion (or 96 percent of all COPS obligation 

amounts). 

Third, to describe the distribution of obligations relative to agency 

population and crime, we selected agencies that reported complete crime 

data—12 months of crime data within a given year—in at least 1 year from 

1990 through 2001, and we merged their records onto the records of the 

agencies for which we had OJP financial information. This last group 

contained 11,187 agencies, and 8,819 (or 78.8 percent) of these agencies 

received at least one COPS grant. The total amount of COPS obligations 

among these agencies was $6.01 billion (or 79 percent of the total amount 

of COPS obligations from 1994 through 2001). 

To analyze the impacts of COPS expenditures on officers and crime, we 

started with the UCR data and included in our samples agencies that met 

specific criteria. First, we identified and included agencies that reported at 

least 1 year of complete crime data—that is, 12 months of crime data in a 

given year—to the UCR from 1990 through 2001, and we included agencies 

only in the years in which they provided complete crime data. 

Second, we excluded from our analysis agencies that the UCR classifies as 

“zero-population” agencies. To avoid double counting of citizens within 

geographic areas, the UCR program assigns population counts only to the 

primary law enforcement agency within each jurisdiction. Consequently, 

transit police, park police, university police, and similar agencies that are 

contained within these jurisdictions are assigned a value of zero for 

population. Because of the fact that jurisdictions among zero-population 

agencies overlap with primary agencies, calculation of precise per capita 

crime rates for these nonprimary agencies is problematic. Many state 

police agencies also enforce laws among populations that are policed by 

other local agencies, which also makes problematic calculating per capita 

crime rates for state police agencies. Additionally, given that state police 

Data Used in Our Analysis 

of Officers and Crime 
Appendix I: Objectives, Scope, and 

Methodology 

Page 32 GAO-06-104 Community Policing Grants 

agencies often have multiple substations in varied locations throughout 

the state, the correct allocation of the proportion of federal dollars to each 

substation is unknown. As a result, we excluded zero-population and state 

police agencies from our analysis. Further, we included in our analysis 

agencies whose crime records we were able to merge-match and link with 

OJP financial data about COPS and other federal law enforcement grant 

expenditures, as well as link with Bureau of Economic Analysis and 

Census data on economic and population characteristics. 

Overall, we identified 13,133 agencies that provided complete crime data 

for at least 1 year from 1990 through 2001, that were not zero-population 

agencies, and that we were able to link to our other data sources. For 

example, in 1990, we found 10,160 agencies out of 17,608 that met our 

conditions. These 10,160 agencies represented 57.7 percent of the agencies 

that were included in the 1990 data that we obtained from the FBI, but 

they contained 93.2 percent of the crimes included in the 1990 data. That 

the agencies that we included in our sample in 1990 represented about 58 

percent of all agencies but 93 percent of all crimes indicates that most of 

the agencies that we omitted with our criterion of providing complete 

crime data within a year were small agencies that reported relatively small 

amounts of crime to the national total. For 2001, the 9,733 agencies that 

reported complete crime data and were not zero-population agencies 

represented 49.1 percent of all agencies in the UCR data in 2001 and 

covered 94.8 percent of all crimes (table 3). 

In our analysis of officers and crime, we further limited our sample to 

agencies that covered populations serving 10,000 or more persons. 

Complete crime data for agencies serving populations of fewer than 10,000 

persons were missing for a large percentage of agencies, and we 

determined that the data for these smaller agencies were unreliable for the 

purposes of this report. In 1990, we found 4,051 of agencies serving 

populations of 10,000 or more persons, which represented 23 percent of 

the agencies included in the data that we received from the UCR for 1990 

but also represented 86.8 percent of the crimes (table 3). 
Appendix I: Objectives, Scope, and 

Methodology 

Page 33 GAO-06-104 Community Policing Grants 

Table 3: Law Enforcement Agencies Reporting to the UCR and in Our Analysis 

Dataset 

 Year 

Database 1990 2001 

 

Uniform Crime Report data provided by the FBI

Number of agencies 17,608 100.0% 19,820 100.0%

Number of index crimesa 13,962,575 100.0% 11,092,578 100.0%

Agencies in the UCR data that reported complete crime data in at least 1 yearb

Number of agencies 12,168 69.1% 11,802 59.5%

Number of index crimes 13,456,345 96.4% 10,902,718 98.3%

GAO primary analysis dataset—agencies reporting complete crime data in at least 

1 year and not zero population agenciesb

Number of agencies 10,160 57.7% 9,733 49.1%

Number of index crimes 13,010,329 93.2% 10,520,533 94.8%

Percentage of population 

in UCR data covered by 

agencies c 86.6% c 84.5%

GAO dataset used in the analysis of officers and crime—from the primary analysis 

dataset, agencies serving populations of 10,000 and more persons

Number of agencies 4,052 23.0% 4,247 21.4%

Number of index crimes 12,113,789 86.8% 9,797,096 88.3%

Percentage of population 

in UCR data covered by 

agencies c 76.6% c 76.8%

Source: GAO analysis of Uniform Crime Report data. 

a

The number of index crimes reported in the data that we received from the FBI is less than the 

number of index crimes that appears in Crime in the United States: Uniform Crime Reports. For 

example, for 2001, Crime in the United States reported a total of 11,876,669 index crimes, while the 

data that we received from the UCR reported 11,092,578 index crimes. The totals reported in Crime 

in the United States are the estimated total numbers of index crimes in the nation. These totals are 

based upon the crime reports that the FBI receives from individual agencies and upon the 

methodology that the FBI uses to estimate crimes occurring in agencies that did not submit complete 

crime reports. The data that we received from the FBI contain the crimes actually reported by law 

enforcement agencies to the FBI. 

b

“Complete crime data” means that an agency reported 12 months of crime data in a given year. 

c

Not applicable. 

To assess changes in reported policing practices, we analyzed data from 

two separate surveys of nationally representative samples of local law 

enforcement agencies. The surveys asked key officials at agencies about 

the types of policing practices that they reportedly used. Both surveys 

Data Used in Our Analysis 

of Reported Changes in 

Policing Practices 
Appendix I: Objectives, Scope, and 

Methodology 

Page 34 GAO-06-104 Community Policing Grants 

consisted of two administrations or waves of observations on the agencies 

in their respective samples. The first survey, the National Survey of 

Community Policing Strategies (or Policing Strategies Survey), was 

administered in 1993 and again in 1997. A total of 1,269 agencies in the 

1993 and 1997 samples responded to both waves of the survey. We limited 

our analysis to the 1,188 agencies that had complete data on each of the 

policing practices items that we included in our analysis and that we were 

able to link to our larger database on crime, officers, money, and 

economic conditions. These agencies amounted to about 94 percent of the 

agencies that responded to both waves of the survey. For comparability 

with our analysis of the effects of COPS grants on officers and crime, we 

limited our analysis to the sample of agencies that served jurisdictions 

with populations of 10,000 or more persons. 

The second survey, which we call the National Evaluation of COPS Survey, 

was conducted by the National Opinion Research Center for the Urban 

Institute in its national evaluation of the implementation of the COPS 

program.8

 Of the 1,270 agencies that responded to both the 1996 and 2000 

administrations of the survey, we were able to link the data from 1,067 

agencies to our larger database on crime, officers, money, and economic 

conditions. We restricted our analysis to agencies that served jurisdictions 

having populations of 10,000 or more persons, and we excluded from our 

analysis state police agencies and other special police agencies. (See app. 

VII for more information about the sample of agencies that we analyzed.) 

Prior to developing our database, we assessed the reliability of each data 

source. To assess the reliability of the various data sources, we (1) 

performed electronic testing for obvious errors in accuracy and 

completeness; (2) reviewed related documentation, including data 

dictionaries, codebooks, and published research reports that made use of 

the data sources; and (3) worked closely with agency officials to identify 

any data problems. When we found discrepancies (such as nonpopulated 

fields or what appeared to be data entry errors) we brought them to the 

agencies’ attention and worked with them to correct the discrepancies 

before conducting our analyses. We determined that the data were 

sufficiently reliable for the purposes of our report. 

 8

See Roth, Jeffrey., et al., National Evaluation of the COPS Program—Title I of the 1994 

Crime Act. 

Reliability and 

Validity of the Data 

That We Used 
Appendix I: Objectives, Scope, and 

Methodology 

Page 35 GAO-06-104 Community Policing Grants 

In our regression analysis of the effects of COPS expenditures on crime, 

we use the UCR reported crime rates as our dependent variables. Crimes 

reported to the UCR are those brought to the attention of law enforcement 

agencies and subsequently reported to the UCR, or reported crimes. 

Reported crimes are a subset of all crimes committed, which is the sum of 

reported crimes plus crimes that are not reported to the police. Our 

ultimate interest, however, lies in determining whether COPS 

expenditures affected the crime rate for all crimes, whether or not they 

were reported to the UCR. This raises issues related to analyzing reported 

crimes to learn about all crimes. 

Because data on all crimes—reported and unreported—committed within 

local jurisdictions are unavailable in national data systems, we use the 

data on reported crimes. The nature of the relationship between reported 

crimes and all crimes therefore determines whether the results of our 

analysis of COPS expenditures on reported crime would lead to biased 

estimates of the effects of COPS expenditures on all crimes. Under certain 

circumstances, it is possible that our analysis of the effects of COPS on the 

reported crime rate could lead to overestimates of the effect of COPS on 

the crime rate for all—reported plus unreported—crimes. This would lead 

us to overstate the effect of COPS in reducing crime. 

Several conditions could lead to overestimates of the effects of COPS 

expenditures on reducing crime. If the reported crime rate and the crime 

rate for all crimes diverge, we would attribute to COPS a larger reduction 

in crime than is warranted. If these crime rates diverge, the reported crime 

rate would either decline at a faster rate or increase at a slower rate than 

the rate for all crimes, and our analysis of the effects of COPS on the 

reported crime would reveal either larger declines or smaller increases 

than would occur if we had data on the rate for all crimes. A divergence 

between the reported crime rate and rate for all crimes could arise for 

either or both of two reasons: Citizens do not report all of the crimes they 

experience to the police, or the police do not record and send to the UCR 

all of the crimes that citizens report to them. 

To assess whether citizens decreased the rate at which they reported 

crimes to the police, we reviewed data from the National Crime 

Victimization Survey (NCVS). These data are drawn from a nationally 

representative sample of households and are gathered independently of 

the police agencies that report crime to the UCR. They therefore provide a 

measure of crime that is independent of the reporting practices of police 

agencies. Respondents in the NCVS are asked about their experiences as 

victims of crimes. If respondents were victims of crime, they are asked if 
Appendix I: Objectives, Scope, and 

Methodology 

Page 36 GAO-06-104 Community Policing Grants 

they or others reported the criminal victimization to the police. Using the 

NCVS data, it is possible to assess whether the rate at which citizens 

report crimes to the police has changed over time. These data show that 

during the 1990s, victims generally increased the rate at which they 

reported crimes to the police. As figure 5 shows, the decline in violent 

crime over the decade was steeper for all crimes reported in the survey 

than for the violent crimes reported to the police. Consequently, because 

the rates diverged rather than converged, victims’ practices of reporting of 

crime to the police during the 1990s are not likely to lead us to 

overestimate the effects of COPS grants on the crime rate. 

Figure 5: Violent Crimes and Violent Crimes Reported to the Police, as Reported in 

the National Criminal Victimization Survey and Including Homicides from the 

Uniform Crime Reports, 1990-2001 

For police recording practices to lead to overestimates of the effects of 

COPS grants on crime, it would be necessary for the agencies that 

received COPS grants to decrease the rate at which they recorded and 

reported crimes to the UCR. Research on police recording practices 

Actual number of sworn officers per capita

Predicted number of sworn officers per capita in the absence of COPS grant expenditures 

(if COPS grant expenditures were equal to zero)

Source: GAO analysis of Uniform Crime Report, Office of Justice Programs, National Center for Health Statistics, U.S. Census Bureau, 

 and Bureau of Economic Analysis data.

1991 1992 1993 1997 1998 1999 2000 2001 1994 1995 1996

Calendar year

Estimated number of officers per 10,000 persons

18.0

18.5

19.0

19.5

20.0

20.5

21.0

21.5

22.0

22.5

Pre-COPS program period COPS program period
Appendix I: Objectives, Scope, and 

Methodology 

Page 37 GAO-06-104 Community Policing Grants 

suggests that agencies are unlikely to underreport serious crimes, such as 

murder, rape, robbery, and aggravated assault. Other studies found, 

second, that as police agencies adopt computer technology and become 

more sophisticated in recording crimes, they became more likely to 

increase the rate at which they included all citizen-reported crimes to the 

UCR.9

 As COPS MORE grants provided funds for technology—such as 

laptop computers in police cars—that would have increased the level of 

sophistication within agencies, COPS grantee agencies would be more 

likely to report a larger percentage of the crimes that citizens drew to their 

attention. Consequently, changes in police reporting practices that stem 

from COPS grants and lead to increases in police reporting of crimes to 

the UCR are likely to lead us to underestimate the magnitude of effects of 

COPS grants on reducing crime. 

Two other conditions that could affect our estimates include the following: 

(1) Criminals who commit the crimes that are not reported to the police 

are unresponsive to the effects of COPS expenditures, and (2) as the 

number of police increase, the number of reported crimes increases, 

independently of the true crime rate. 

If criminals who commit crimes that go unreported to the police are 

unresponsive to police presence, then we would overestimate the effects 

of COPS on crime only if criminals changed their behavior to victimize 

more persons who would be unlikely to report crimes to the police. This 

appears to be an unlikely occurrence, as the NCVS data show a 

convergence between the total number of criminal victimizations, 

especially for violent crimes, and the number of crimes reported to the 

police. 

Second, if the size of the police force systematically affects the willingness 

of victims to report crime to the police or a police department’s likelihood 

of recording and reporting to the UCR crime victims’ reports, then these 

changes could lead to biased estimates of the impact on the crime rate. 

However, if changes in reporting behaviors occurred as the result of the 

COPS program, the likely impact on our estimates of the effect of COPS 

 9

Lynch, James P., “Exploring the Sources of Non-response in the Uniform Crime Reports.” 

Paper presented at the Annual Meetings of the American Society of Criminology Research 

Conference, November 19, 2003. 
Appendix I: Objectives, Scope, and 

Methodology 

Page 38 GAO-06-104 Community Policing Grants 

grants on crime through their effects on the number of officers is that we 

would underestimate the effects of the grants on crime.10

Given these considerations, our analysis of the effects of COPS 

expenditures on crime is more likely to underestimate than overestimate 

the effect of COPS funds on changes in the true crime rate. 

 10Levitt uses three methods to estimate the bias associated with changes in reporting 

practices in efforts to estimate the effects of changes in the size of the police force on 

crime rates. He concludes that ignoring this effect will lead researchers to understate the 

benefits associated with increases in the size of the police force. See Levitt, Steven D., “The 

Relationship between Crime Reporting and Police: Implications for the Use of Uniform 

Crime Reports,” Journal of Quantitative Criminology, Vol. 14, No. 1,1998: pp. 61-81. 
Appendix II: Background on the COPS 

Program and Studies of the Impacts of COPS 

Grants on Crime 

Page 39 GAO-06-104 Community Policing Grants 

Established in October 1994 by the Attorney General to implement the 

administration of community policing grants under the Violent Crime 

Control and Law Enforcement Act (VCCLEA) of 1994,1

 the Office of 

Community Oriented Policing Services announced its first grant program 

in November 1994. Prior to its establishment, in December 1993 the 

Department of Justice began making community policing grants to state 

and local law enforcement agencies that the COPS Office monitored. In 

1993, DOJ awarded community policing grants under the Police Hiring 

Supplement Program, which was established by the Supplemental 

Appropriations Act of 1993 (P.L. 103-50 (1993)). The grants made under 

this program were funded by DOJ’s Bureau of Justice Assistance.2

Two goals of the COPS Office were to advance community policing by 

providing funding for 100,000 community policing officers and to promote 

the practice of community policing, an approach to policing that involves 

the cooperation of law enforcement and the community in identifying and 

developing solutions to crime problems. COPS attempted to achieve these 

goals by providing law enforcement agencies with grants to hire officers, 

purchase equipment, and implement innovative policing practices. 

According to our analysis of Office of Justice Programs data, from 1994 

through 2001, the COPS Office distributed more than $7.6 billion in grants. 

Grants were made in a variety of grant program funding categories. Table 

2 in appendix I contains more information about these funding categories. 

The largest amount of COPS grant funds obligated—about $4.8 billion, or 

64 percent of the total—was in the form of hiring grants. These grants 

required agencies to hire new officers and at the same time to indicate the 

types of community policing strategies that they intended to implement. 

Hiring grants paid a maximum of $75,000 per officer over a 3-year period 

(or at most 75 percent of an officer’s salary) and generally required that 

local agencies cover the remaining salary and benefits with state or local 

funds. Hiring programs authorized under VCCLEA and administered by the 

COPS Office included the Phase I program, which funded qualified 

applicants who had applied for the Police Hiring Supplement but were 

denied because of the limited funds available; COPS AHEAD (Accelerated 

Hiring, Education, and Deployment) for municipalities with populations 

 1

P.L. 103-322 (1994), 42 U.S.C. § 3796dd. 

2

In this report, when we refer to COPS grants, we include both the grants made under the 

Police Hiring Supplement and the community policing grants authorized under VCCLEA. 

Appendix II: Background on the COPS 

Program and Studies of the Impacts of COPS 

Grants on Crime 

COPS and Other Local 

Law Enforcement 

Grants Distributed 

throughout the 1990s 
Appendix II: Background on the COPS 

Program and Studies of the Impacts of COPS 

Grants on Crime 

Page 40 GAO-06-104 Community Policing Grants 

50,000 and above; and COPS FAST (Funding Accelerated for Smaller 

Towns) for towns with populations below 50,000. In June 1995, Phase I, 

COPS AHEAD, and COPS FAST were replaced by the Universal Hiring 

Program. 

The next largest grant category was the Making Officer Redeployment 

Effective (MORE) grant program, which provided funds to law 

enforcement agencies to purchase equipment and hire civilians, with the 

goal of expanding the amount of time spent on community policing. COPS 

obligated more than $1.3 billion—or about 17 percent of total 

obligations—as MORE grants. Additional COPS grant programs provided 

funds for specific innovations in policing. For example, the Distressed 

Neighborhoods Pilot Project grants provided funds to communities with 

high levels of crime or economic distress to hire officers and implement a 

variety of strategies to improve public safety, and the Methamphetamine 

Initiative provided funds to state and local agencies to support a variety of 

enforcement, intervention, and prevention efforts to combat the 

methamphetamine problem. About $418 million—or about 5.5 percent of 

the total—was obligated under these innovative grant programs. The 

COPS Office also provided grants for a variety of other purposes, including 

funding to meet the community policing training needs of officers and 

representatives of communities and local governments (through a network 

of Regional Community Policing Institutes), and grants to law enforcement 

agencies to hire and train school resource officers to help prevent school 

violence and improve school and student safety (the COPS in Schools 

Program). Over $1 billion—or about 14 percent of total obligations—was 

obligated among these miscellaneous grant programs. 

In each year, the COPS Office was required to distribute half of the grant 

funds to agencies in communities whose populations exceeded 150,000 

persons and half of the grant funds to agencies in communities with 

populations of 150,000 or fewer persons.3

During the 1990s, other federal law enforcement grant programs also 

provided funds to state and local law enforcement agencies for hiring 

 3

Of funds available in any fiscal year, up to 3 percent were available for use for technical 

assistance or for evaluations or studies carried out or commissioned by the Attorney 

General. The requirement to allocate the funds by size of agency population applies to the 

remaining funds in any fiscal year (42 U.S.C. § 3793 (a)(11)(B)). In addition, the COPS 

Office had a national coverage requirement to ensure that no state received less than 0.5 

percent of total funding. 
Appendix II: Background on the COPS 

Program and Studies of the Impacts of COPS 

Grants on Crime 

Page 41 GAO-06-104 Community Policing Grants 

officers and other crime prevention purposes. The Edward Byrne 

Memorial State and Local Law Enforcement Assistance (Byrne Formula 

Grant Program) 4 was a variable pass-through grant program administered 

by the Bureau of Justice Assistance (BJA). According to our analysis of 

data that we obtained from OJP, from 1990 through 2001, the Byrne 

Formula Grant Program distributed between $415 million and $520 million 

in grants. States were required to pass through to local jurisdictions 

amounts of funding based upon a variable pass-through formula. Byrne 

Formula Grant funds could be used to provide for personnel, equipment, 

training, technical assistance, and information systems, among other 

purposes. According to an evaluation of the Byrne formula grant program, 

about 40 percent of Byrne subgrant funds—the amounts passed through 

the states to local jurisdictions—were for multijurisdictional task forces.5

In addition to the formula grant program, there also was a Byrne 

discretionary grant program. According to an official at the Bureau of 

Justice Statistics (BJS), a large percentage of the Byrne discretionary 

funds were targeted for specific programs. 

The Local Law Enforcement Block Grant (LLEBG) Program was also 

administered by BJA.6

 The LLEBG grant funds amounted to about an 

average of $475 million per year from 1996 through 2000. According to BJS 

officials, these funds were allocated by a formula based upon violent 

crimes as reported in FBI’s crime index. LLEBG funds were available to 

local governments for hiring law enforcement officers, paying overtime, 

purchasing equipment, as well as several other purposes. According to the 

Urban Institute’s evaluation of the implementation of the COPS program, 

agencies that received COPS grants reported using both Byrne and LLEBG 

funds to support their transitions to community policing.7

Additional grant programs that provided funds to local law enforcement 

agencies included the Juvenile Accountability Incentive Block Grants, 

 4

42 U.S.C. § 3750 et seq. 

5

Dunworth, Terence, Peter Haynes, and Aaron J. Saiger, National Assessment of the Byrne 

Formula Grant Program, Washington, D.C.: National Institute of Justice Research in Brief, 

June 1997. 

6

Local Law Enforcement Block Grant Program, as authorized by the Omnibus Consolidated 

Rescissions and Appropriations Act of 1996 (P.L. 104-134). 

7

Roth, Jeffrey A., et al., National Evaluation of the COPS Program—Title I of the 1994 

Crime Act, Washington, D.C.: National Institute of Justice Research Report, August 2000. 
Appendix II: Background on the COPS 

Program and Studies of the Impacts of COPS 

Grants on Crime 

Page 42 GAO-06-104 Community Policing Grants 

Weed and Seed Grants, and several Office on Violence Against Women 

grants, according to a BJS official. 

The amount of COPS funding was more than sufficient to fund the federal 

portion for 100,000 officers. According to the Attorney General’s report, 

from 1994 through 2000, the COPS Office awarded more than 30,000 grants 

to over 12,000 law enforcement agencies and funded more than 105,000 

community policing officers.8

 However, a research report by the Heritage 

Foundation questioned how effective the COPS Office had been in putting 

100,000 officers on the street.9

 The study analyzed trends in the number of 

officers and concluded that the COPS program had not added 100,000 

additional officers above historic trends. In its review of the COPS Office’s 

performance for the fiscal year 2004 budget, the Office for Management 

and Budget (OMB) indicated that by 2002, COPS grants funding was 

sufficient for almost 117,000 officers, a number that exceeded the 

program’s original commitment to fund 100,000 officers.10 At the same 

time, OMB acknowledged that fewer than 90,000 officers had been hired or 

redeployed to the street. OMB reported that the COPS Office counted 

88,028 COPS-funded officers on duty as of August 2002—or about 75 

percent of funded officers. In their report of October 2002 on the COPS 

program, researchers at the Urban Institute updated earlier estimates of 

COPS-funded officers.11 They projected that over the years from 1994 

through 2005, COPS-funded officers would add between 93,400 and 

102,700 officers to the nation’s communities on a temporary basis, but that 

not all of these officers would be available for service at any one point in 

time. They further estimated that the permanent impact of COPS, after 

taking into account postgrant attrition of officers and civilians, would be 

between 69,100 and 92,200 officers. 

 8

Attorney General of the United States, Report to Congress: Office of Community Oriented 

Policing Services, Washington, D.C.: U.S. Department of Justice, September 2000. 

9

Davis, Gareth, et al., “The Facts about COPS: A Performance Overview of the Community 

Oriented Policing Services Program,” Washington, D.C.: The Heritage Foundation, 

September 25, 2000. 

10Executive Office of the President, Performance and Management Assessments: Budget 

of the United States Government, Fiscal Year 2004, Washington, D.C.: White House, 2003. 

11Koper, Christopher S., et al., Putting 100,000 Officers on the Street: A Survey-Based 

Assessment of the Federal COPS Program, Washington, D.C.: The Urban Institute, October 

2002. 

Debates over whether 

the COPS Office Met 

Its Goals for Officers 

and Promoted 

Community Policing 
Appendix II: Background on the COPS 

Program and Studies of the Impacts of COPS 

Grants on Crime 

Page 43 GAO-06-104 Community Policing Grants 

In addition to promoting the hiring of officers, the COPS Office sought to 

promote community policing. COPS hiring grant applications asked 

agencies to report the types of practices that they planned to implement 

with their grants, such as identifying crime problems by looking at records 

of crime trends and analyzing repeat calls for service, working with other 

public agencies to solve disorder problems, locating offices or stations 

within neighborhoods, and collaborating with community residents by 

increasing officer contact with citizens and improving citizen feedback. In 

2000, the Attorney General reported that 87 percent of the country was 

served by departments that practiced community policing.12

Studies that have addressed the extent to which the COPS Office grants 

caused the spread of community policing suggest that COPS grants 

accelerated the adoption of these practices but did not launch the spread 

of community policing. The Police Foundation’s study of community 

policing practices during 1993—1 year before the COPS Office began 

making grants—indicated that the practice of community policing was 

fairly widespread, especially in larger police departments.13 The Police 

Foundation researcher reported that 47 percent of the agencies surveyed 

in 1993 reported that they either were in the process of adopting or had 

adopted community policing, but that 86 percent of municipal agencies 

with more than 100 sworn personnel were either in the process of 

implementing or had implemented community policing. In their evaluation 

of the implementation of the COPS program, Urban Institute researchers 

credited COPS with promoting community policing, but the researchers 

concluded that COPS funds seemed to have fueled movements that were 

already accelerating rather than have caused the acceleration. In a later 

report, they pointed out that for large agencies, the problem-solving 

practices that they examined were already widespread by 1995, and almost 

no COPS grantees reported adopting problem-solving practices for the 

first time between 1998 and 2000.14

Some of the types of practices that agencies planned to implement with 

their COPS grants correspond with approaches to policing that recent 

 12Attorney General of the United States, Report to Congress, 2000. 

13Wycoff, Mary Ann, Community Policing Strategies: A Comprehensive Analysis, 

Washington, D.C.: The Police Foundation, November 1994. 

14Johnson, Calvin C., and Jeffrey A. Roth, The COPS Program and the Spread of 

Community Policing, 1995-2000. Washington, D.C.: The Urban Institute, June 2003. 
Appendix II: Background on the COPS 

Program and Studies of the Impacts of COPS 

Grants on Crime 

Page 44 GAO-06-104 Community Policing Grants 

reviews of policing practice suggest are effective in preventing crime. 15

For example, our review of policing practices indicates that problemsolving policing and place-oriented policing practices—such as those in 

which officers attempt to identify the locations where crime occurs 

repeatedly and to implement procedures to affect crime—are among the 

types of practices that research has demonstrated to be effective in 

preventing crime. These practices were among the types that agencies 

could implement with their COPS grants. 

In 2000, the Attorney General reported that COPS-funded officers helped 

to reduce crime.16 The Attorney General’s report to Congress asserted that 

the drop in crime that occurred after 1994 was more than would have been 

expected in the absence of the passage of VCCLEA and the creation of the 

COPS Office. As evidence of the impact of COPS grants on crime, it 

proffered the inverse relationship between increases in the per agency 

number of police officers and decreases in the per agency levels of violent 

crimes. 

Studies of the impact of COPS grants on crime that attempted to take into 

account factors other than just the underlying trends in crime were 

released in 2001. A COPS Office-funded study examined the impact of 

COPS grants on local crime rates in over 6,000 communities from 1995 

through 1999.17 Analyzing changes in crime rates in communities that had 

received COPS grants, the study concluded that COPS hiring grants were 

effective in reducing crime and that COPS grants for innovative policing 

practices had larger impacts on reducing violent and property crime than 

did other types of COPS grants. However, a study released by the Heritage 

Foundation, which was based upon the analysis of county-level data, was 

 15Skogan, Wesley, and K. Frydl, “The Effectiveness of Police Activities in Reducing Crime, 

Disorder, and Fear,” in Skogan, W., and K. Frydl, (eds.) Fairness and Effectiveness in 

Policing: The Evidence, Washington, D.C.: National Academies Press, pp. 217-251, 2004. 

16Attorney General of the United States, Report to Congress, 2000. 

17Zhao, J., and Q. Thurman, A National Evaluation of the Effect of COPS Gants on Crime 

from 1994 to 1999. Report submitted to the Office of Community Oriented Policing 

Services, Washington, D.C.: U.S. Department of Justice, December 2001. In 2004, Zhao and 

Thurman released a revised report on the impacts of COPS grants on crime covering the 

years from 1994 through 2000. In their 2004 report, the estimated effects of hiring grants 

were larger and the estimated effects of innovative grants were smaller than they reported 

in 2001. 

Debates about COPS’ 

Contribution to the 

Decline in Crime in 

the 1990s 
Appendix II: Background on the COPS 

Program and Studies of the Impacts of COPS 

Grants on Crime 

Page 45 GAO-06-104 Community Policing Grants 

unable to replicate the findings of the COPS-funded study.18 Specifically, 

the Heritage study found no effect of COPS hiring grants on crime rates, 

but it found that grants for specific problems—such as gangs, domestic 

violence, and illegal use of firearms by youth—were associated with 

reductions in crime. In addition, our review of the COPS-funded study 

found that its methodological limitations were such that the study’s results 

should be viewed as inconclusive.19

The inconclusiveness of the findings of studies was reflected in OMB’s 

assessment of the performance of the COPS program. According to OMB, 

although the COPS Office used evaluation studies to assess whether its 

grants had an impact on crime, the results of the findings were 

inconclusive, and OMB rated the COPS program as “Results Not 

Demonstrated” in 2004 using its Program Assessment Rating Tool (PART). 

Assessing whether COPS funds contributed to the decline in crime during 

the 1990s is complicated by many factors. Nationwide, the decline in crime 

began before 1993, which was before the COPS program made its first 

grants. According to the FBI’s data on index crimes—the violent crimes of 

murder, rape, aggravated assault, and robbery and the property crimes of 

burglary, larceny, and motor vehicle theft—the decline in the overall index 

crime rate, as well as the property and violent crime rates started as early 

as 1991 or 1992 (fig. 6).20

 18Muhlhausen, David. Do Community Oriented Policing Services Grants Affect Violent 

Crime Rates (Washington, D.C.: The Heritage Foundation, May 25, 2001). 

19Our review of this study was reported in GAO, Technical Assessment of Zhao and 

Thurman’s 2001 Evaluation of the Effects of COPS Grants on Crime, GAO-03-867R 

(Washington, D.C.: June 13, 2003). 

20Although arson is included in the crime index, the FBI reports that it excludes arson 

crimes from its estimates of national crime totals because of limited reporting of arson by 

law enforcement agencies to the UCR. 

Issues in Assessing 

the Contribution of 

COPS Grants to the 

Decline in Crime in 

the 1990s 
Appendix II: Background on the COPS 

Program and Studies of the Impacts of COPS 

Grants on Crime 

Page 46 GAO-06-104 Community Policing Grants 

Figure 6: Total Index, Violent, and Property Crime Rates per 100,000 Persons, 1990-2001 

As COPS grants cannot be the cause of the start of the decline in crime 

rates, the other factors that led to the decline in the crime rate could also 

have affected the decline in crime during the period that the COPS Office 

made its grants. Factors such as a downturn in handgun violence, the 

expansion of imprisonment, a steady decline in adult violence, changes in 

drug markets, and expanding economic opportunities are among those 

suggested as related to the decline in crime—especially violent crime—in 

3,500

4,200

4,900

5,600

6,300

7,000

100,000 100,000

1990 1994 1995 2000 2001

Index and property crime rates per 100,000 population Violent crime rate per 100,000 population

Pre-COPS grant period COPS grant period

Calendar year

Violent crime rate

Index crime rate

Property crime rate

Source: GAO analysis of Uniform Crime Report data.

0

200

400

600

800
Appendix II: Background on the COPS 

Program and Studies of the Impacts of COPS 

Grants on Crime 

Page 47 GAO-06-104 Community Policing Grants 

the 1990s. To the extent that these factors also are correlated with the 

disbursement of COPS funds, this increases the challenges involved in 

isolating the effects of COPS grants. 

Other federal funds for local law enforcement could also have contributed 

to expanding the number of police officers and contributed to declines in 

crime. If the distribution of non-COPS funds such as LLEBG and Byrne 

grants is correlated with that of COPS funds, and if research does not take 

these funds into account, a study could attribute some of the effect on 

crime of these other grant funds to COPS grants. 

COPS grants were distributed in ways that make rigorous evaluations of 

their causal impacts difficult to implement. Receipt of a COPS grant was 

not randomly assigned; therefore, it is difficult to determine whether the 

agencies that received grants are the same ones that, in the absence of the 

grant, would have experienced reductions in crime. The amount of funding 

certain agencies receive may also relate to the agency’s ability to combat 

crime. For example, certain police chiefs may be more capable than others 

at acquiring funds and also more up-to-date on policing methods. This 

underlying capacity of an agency to organize policing, rather than the 

receipt of a particular grant, would then be the cause of a crime decline as 

opposed to a particular grant. Additionally, COPS grants were fairly 

widespread throughout police departments and the nation as a whole. This 

distribution of grants leaves relatively few unfunded agencies to serve as 

comparison groups against which to assess the performance of the 

agencies that received COPS grants. The roughly 12,000 agencies that the 

former Attorney General reported received COPS grants by 2000 represent 

about 61 percent of the agencies that reported crime to the Uniform Crime 

Reports. 

The mechanisms by which COPS funds could affect crime have not been 

explicitly examined. For example, the two prior studies that we cited did 

not examine whether COPS grants potentially affect crime through 

changes in police officers or through changes in policing practices, both of 

which may have been affected by COPS funds. Additional officers may 

affect crime by increasing police presence, by increasing arrests that lead 

to incapacitation of offenders, or by deterring offenders by increasing the 

likelihood of capture. Changes in policing practices toward problemsolving or place-oriented practices that focus police resources on 

recurring crime problems could also lead to reductions in crime. 

Appropriate methodologies from research on crime have been developed 

to address issues that could confound efforts to assess the impacts of 
Appendix II: Background on the COPS 

Program and Studies of the Impacts of COPS 

Grants on Crime 

Page 48 GAO-06-104 Community Policing Grants 

COPS grants on crime rates. For example, if COPS grants are to affect 

crime through their impacts on the number of officers, then isolating the 

effects of increases in officers on crime presents a challenge in assessing 

the direction of the relationship between officers and crime. If additional 

officers are hired in response to increases in crime rates, then it could 

appear that crime causes officers. Alternatively, if additional officers lead 

to reductions in crime below the levels that they would have been without 

the officers, then it would appear that officers caused changes in crime. To 

isolate the causal effect of COPS grants, researchers employ the use of 

instruments for causal variables. One suggestion in the research literature 

for an instrument for police officers is COPS hiring grants.21 To the extent 

that COPS hiring grants buy only officers, COPS hiring grants can be used 

as an instrument for the actual number of police officers and therefore be 

used to estimate the relationship between crime and police officers in a 

way that takes into account the possibility of this simultaneous 

relationship. 

Second, particular forms of statistical models take advantage of 

information about the variation in the amount and timing of COPS grants 

among agencies to assess how changes in the number of sworn officers 

and crime rates are associated with these two sources of variation. These 

fixed-effects regression models use a panel of data—or repeated 

observations on the same units, in this case, police agencies, over several 

time periods—to assess the effects of changes in the number of sworn 

officers and crime rates that are associated with variation in the timing 

and amount of COPS grant expenditures. These regression methods also 

allow for the introduction of controls for unobserved preexisting 

differences between units (agencies) and differences over time within 

units. Incorporating each agency’s underlying trajectories (or growth rate 

trends) in crime rates and sworn officers into the modeling of the effects 

of COPS funds allow for explicit comparisons within groups of agencies 

sharing similar trajectories, which helps to control for potential biases 

associated with preexisting trends.22 By identifying and explicitly modeling 

the mechanisms through which a program could have its effects—such as 

COPS funds leading to increases in the number of officers and their effects 

 21Evans, William N. and Emily Owens. “Flypaper COPS,” College Park, Maryland: University 

of Maryland. Available online at 

www.bsos.umd.edu/econ/evans/wpapers/Flypaper%20COPS.pdf, 2005. 

22This methodology was implemented by Evans and Owens (2005). 
Appendix II: Background on the COPS 

Program and Studies of the Impacts of COPS 

Grants on Crime 

Page 49 GAO-06-104 Community Policing Grants 

on crime—the possibility of a spurious relationship between inputs (such 

as COPS funds) and outcomes (such as crime) can be minimized. 
Appendix III: COPS Grant Obligation and 

Expenditure Patterns 

Page 50 GAO-06-104 Community Policing Grants 

This appendix addresses how COPS obligations were distributed among 

local law enforcement agencies in relation to the populations they served 

and the crimes in their jurisdictions. It also addresses how much of the 

obligated amounts agencies spent. Specifically, it covers (1) the amount of 

COPS obligations between 1994 and 2001, (2) the distribution of grant 

funds to larger and smaller agencies relative to total index and violent 

crimes, (3) the number of agencies in our sample that received COPS 

grants, (4) the amounts of COPS expenditures, and (5) the amount of these 

expenditures relative to total local law enforcement expenditures. 

Our analysis showed that from 1994 through 2001, COPS obligated more 

than $7.32 billion to 10,680 agencies for which we were able to link OJP 

financial data on COPS obligations to the records of law enforcement 

agencies.1

 As shown in table 4, about $4.7 billion (or 64 percent) of these 

obligations were for hiring grants. Equipment and redeployment grants 

made under the MORE category of grants amounted to about $1.2 billion 

(or about 17 percent) of total obligations. 

Table 4: COPS Grant Obligations 1994-2001, by COPS Grant Program 

COPS grant program category Obligations 

Amount 

(in billions of dollars)a

Percentage

of totalb

Total, all grants $7.32 100.0%

Hiring grants $4.69 64.1%

MORE grants $1.22 16.7%

Innovative grants $0.42 5.7%

Miscellaneous grants $1.00 13.7%

Source: GAO analysis of Office of Justice Programs financial data. 

Note: Table 2 in appendix I identifies the specific grant programs that we classified into these four 

categories of grants. 

a

Amounts for each grant program category may not add up to total because of rounding. 

b

The percentages may not add up to 100 percent because of rounding. 

As shown in table 5, from 1994 through 2001, slightly more than half of the 

COPS obligations in the sample of agencies for which we were able to link 

 1

The amount obligated to these agencies was 96.1 percent of the $7.6 billion total in COPS 

obligations reported in the OJP financial data. 

Appendix III: COPS Grant Obligation and 

Expenditure Patterns 

Smaller Agencies 

Received Larger 

Amounts of COPS 

Obligations per Crime 

than Did Larger Ones 
Appendix III: COPS Grant Obligation and 

Expenditure Patterns 

Page 51 GAO-06-104 Community Policing Grants 

OJP financial data to the records of agencies that reported crime and 

population to the FBI’s Uniform Crime Reporting Program2

 went to those 

agencies serving populations of 150,000 or fewer persons and slightly less 

than half went to those agencies serving populations of more than 150,000 

persons, roughly consistent with the requirements of COPS authorizing 

legislation.3

The largest agencies—those serving populations of 150,000 or more 

persons—accounted for more than half of all violent crimes reported to 

the UCR. Specifically, in our sample, these agencies accounted for about 

58 percent of all violent crimes reported in the UCR from 1994 through 

2001. Their share of all violent crimes declined slightly from 60 percent 

from 1994 through 1997 to 57 percent from 1998 through 2001. These 

agencies received about 47 percent of all COPS obligations, a share that is 

disproportionately small relative to their contribution to all violent crimes. 

However, as shown in table 5, the amount of COPS obligations going to 

agencies serving populations of 150,000 or fewer persons and those 

serving populations of more than 150,000 persons was about equal to the 

distribution of all index crimes occurring within these agencies. 

 2

The population data that we used in our analysis came from the UCR, and they may not 

reflect the population information that agencies submitted to the COPS Office on their 

applications. 

3

Each year, the COPS Office was required to allocate half of its grant funds in each year to 

agencies serving populations of 150,000 or fewer persons and half to agencies covering 

populations of more than 150,000 persons. 
Appendix III: COPS Grant Obligation and 

Expenditure Patterns 

Page 52 GAO-06-104 Community Policing Grants 

Table 5: Percentage Distribution of COPS Obligations and Crime from 1994 through 2001, by Population Size Group 

Population size group (number 

of persons) 

Percentage of 

total COPS 

obligations

Percentage of total 

crimes

Percentage of all 

violent crimes 

Percentage of all 

property crimes

Fewer than 10,000 15% 7% 5% 7%

10,000 to fewer than 25,000 13% 11% 8% 12%

25,000 to fewer than 50,000 11% 12% 9% 13%

50,000 to 150,000 15% 22% 19% 22%

Subtotal (150,000 or fewer) 54%a52% 41% 54%

More than 150,000 47%a48% 58% 46%

Total 100% 100% 100% 100%

Source: GAO analysis of Office of Justice Programs financial and Uniform Crime Report data. 

a

The subtotal for agencies serving 150,000 or fewer persons and those serving populations of more 

than 150,000 may not add to 100 percent because of rounding. 

Table 6 shows that law enforcement agencies serving the smallest 

populations received the largest amounts of COPS obligations on a per 

crime basis. For example, agencies serving populations of fewer than 

10,000 persons received, on average, $1,573 per violent crime reported 

from 1994 through 2001. By comparison, agencies serving populations of 

more than 150,000 persons received $418 per reported violent crime. 

Table 6: Per Crime COPS Obligations, by Population Size Group and Category of 

Crime, 1994 through 2001 

Population size group Ratio of total COPS obligations to total crimes 

All index crimes 

Violent 

crimes

Property 

crimes

Fewer than 10,000 $146 $1,573 $160

10,000 to fewer than 25,000 $78 $844 $86

25,000 to fewer than 50,000 $61 $625 $68

50,000 to 150,000 $47 $404 $53

More than 150,000 $67 $418 $80

Total $69 $525 $79

Source: GAO analysis of Office of Justice Programs financial and Uniform Crime Report data. 

Note: Ratios are computed as COPS obligations over the number of each type of crime. The ratio for 

all index crimes is not weighted by the contribution of violent and property crimes to the total. 
Appendix III: COPS Grant Obligation and 

Expenditure Patterns 

Page 53 GAO-06-104 Community Policing Grants 

As shown in table 7, of the 10,680 agencies included in our analysis, just 

under half (49 percent) had received at least their first COPS grant by 

1995, and 71 percent had received at least their first grant by 1996. Of the 

9,845 agencies that received at least one COPS hiring grant, 53 percent had 

received their first hiring grant by 1995, and 73 percent had done so by 

1996. 

Table 7: Number of Agencies That Received at Least One COPS Grant Obligation, 1994-2001, by COPS Grant Program, and 

Year of First COPS Obligation 

Year of first 

COPS grant 

At least one 

COPS grant Hiring grants MORE grants Innovative grants 

Miscellaneous 

grants

1994 241 241 0 0 0

1995 4,989 4,988 0 3 1

1996 2,319 1,965 1,394 265 255

1997 825 750 624 200 17

1998 910 941 231 234 18

1999 803 605 1,010 131 1,339

2000 241 141 216 3 678

2001 352 214 378 13 476

Total number 

of agencies 10,680 9,845 3,853 849 2,784

Source: GAO analysis of Office of Justice Programs financial and Uniform Crime Report data. 

Note: The sum of agencies across specific COPS program categories does not equal the total 

number of agencies that received at least one COPS grant because some agencies may have 

received more than one type of COPS grant in the same year. 

We estimated that about 67 percent of the agencies that reported complete 

crime data to the UCR for at least 1 year from 1990 through 2001 received 

a COPS grant by 2001.4

 The percentages of agencies that received COPS 

grants varied by the size of agencies, as measured by the size of the 

population in the jurisdictions served by the agencies. As table 8 shows, as 

the population served by the agencies increased, the percentage of 

agencies that received a COPS grant also increased. Among the largest 

agencies—those serving populations of more than 150,000 persons—about 

95 percent received a COPS grant. By comparison, among agencies serving 

populations of fewer than 10,000 persons, about 61 percent in our sample 

of agencies received at least one COPS grant. 

 4

According to our definition, an agency reports complete crime data if its reports to the 

UCR contain crime data for all 12 months within a year. 

Most Agencies Had 

Received Their First COPS 

Grant by 1996 
Appendix III: COPS Grant Obligation and 

Expenditure Patterns 

Page 54 GAO-06-104 Community Policing Grants 

Table 8: Percentage of Agencies in GAO’s Primary Analysis Sample That Received 

at Least One COPS Grant Obligation from 1994 through 2001, by Size of Population 

Served by Agencies 

Size of population served by agencies 

(number of persons) 

Number of 

agencies 

Percentage receiving

at least 1 COPS grant

Fewer than 10,000 7,940 60.6%

10,000 to fewer than 25,000 2,673 76.2%

25,000 to fewer than 50,000 1,127 81.7%

50,000 to 150,000 702 85.2%

More than 150,000 185 94.6%

Total, all agenciesa 13,133 67.2%

Source: GAO analysis of Office of Justice Programs financial and Uniform Crime Report data. 

Note: GAO’s primary analysis sample consists of 13,133 agencies that reported at least 12 months of 

crime data in at least 1 year from 1990 through 2001. (See app. I.) 

a

The sum of the agencies in each population size group does not add up to the total of 13,133 

because data on the size of the population served were missing for 506 agencies. Among these 506 

agencies, 276, or 54.5 percent, received at least one COPS grant. 

By 2001, agencies had drawn down about $5 billion in COPS funds (or 

roughly 68 percent of all obligations awarded from 1994 through 2001). As 

figure 7 shows, total COPS expenditures increased annually from 1994 to 

2000. Total expenditures exceeded $900 million per year in each year from 

1998 through 2001, and in 2000, they exceeded $1 billion. COPS hiring 

grant expenditures totaled $3.5 billion (or roughly 70 percent of the 

roughly $5 billion in hiring grant obligations made from 1994 through 

2001). Hiring grant expenditures peaked in 1998—exceeding $690 

million—and declined slightly in 1999 and 2000. 

Total COPS 

Expenditures and Per 

Capita Expenditures 

Peaked in 2000, and 

Smaller Agencies 

Spent More than 

Larger Ones on a Per 

Capita Basis 
Appendix III: COPS Grant Obligation and 

Expenditure Patterns 

Page 55 GAO-06-104 Community Policing Grants 

Figure 7: Annual Expenditures of COPS Grant Funds, by Year 

The number of agencies that spent COPS funds peaked in 1998 and 

declined thereafter, as figure 8 shows. In 1998, more than 7,500 agencies 

were spending COPS funds. However, by 2001, the number had fallen to 

about 6,000. 

All COPS grants expenditures

Hiring grant expenditures

Other COPS grants expenditures

Source: GAO analysis of Office of Justice Programs financial and Bureau of Justice Statistics crosswalk data.

0

250

500

750

1,000

$1,250

Expenditures (in millions of dollars)

1994 1995 1996 1997 1998 1999 2000 2001

Calendar year
Appendix III: COPS Grant Obligation and 

Expenditure Patterns 

Page 56 GAO-06-104 Community Policing Grants 

Figure 8: Number of Agencies That Spent COPS Funds, 1994 through 2001 

COPS expenditures per population in the jurisdictions that spent funds—

per capita expenditures—also increased as the total amount of COPS 

expenditures increased. Total per capita COPS expenditures peaked in 

2000 at $5.6 per person. Hiring grant expenditures per capita similarly 

peaked at $4.8 per person in 2000. The per capita expenditure amounts 

varied by size of agency, as smaller agencies generally spent more on a per 

capita basis than did larger agencies. Agencies serving populations of 

fewer than 10,000 persons spent about twice as much COPS grant monies 

on a per capita basis than did the larger agencies. For example, per capita 

COPS expenditures for agencies serving fewer than 10,000 persons 

averaged $6.6 as compared with about $3.4 for agencies serving 

populations of more than 150,000 persons. 

Spent COPS funds during the current year

Ever spent COPS funds

Source: GAO analysis of Office of Justice Programs financial and Bureau of Justice Statistics crosswalk data.

Number of agencies

1994 1995 1996 1997 1998 1999 2000 2001

Calendar year

0

2,000

4,000

6,000

8,000

10,000

12,000
Appendix III: COPS Grant Obligation and 

Expenditure Patterns 

Page 57 GAO-06-104 Community Policing Grants 

From 1994 through 2001, COPS expenditures amounted to about 1 percent 

of total local expenditures for nationwide police services, based upon BJS 

data on criminal justice expenditures and our analysis of OJP data on 

COPS grant expenditures.5

 From 1994 through 2001, total local 

expenditures for police services increased from about $46 billion to $72 

billion. During the years from 1998 through 2000, when COPS 

expenditures neared and then exceeded $1 billion per year, the 

contribution of COPS expenditures to local police expenditures increased 

to about 1.5 percent of total local expenditures for police services. 

 5

This includes total expenditures for jurisdictions with agencies that received COPS grants 

as well jurisdictions with agencies that did not receive COPS grants. 

COPS Expenditures 

Amounted to about 1 

Percent of All Local 

Law Enforcement 

Expenditures 
Appendix IV: COPS Expenditures Led to 

Increases in Sworn Officers and Declines in 

Crime 

Page 58 GAO-06-104 Community Policing Grants 

This appendix addresses our second reporting objective, which has two 

parts: determining the extent to which COPS grant expenditures 

contributed to increases in the number of sworn officers in police 

agencies, and determining the extent to which COPS grant expenditures 

led to reductions in crime through their effects on sworn officers. 

We found that COPS hiring grants were significantly related to increases in 

sworn officers above levels that would have been expected without the 

expenditures, after controlling for economic conditions in the counties in 

which agencies were located, population composition, and preexisting 

trends in agencies in the growth rate of sworn officers. Further, the effects 

of COPS hiring grants were consistent across several different regression 

models, including those that controlled for state-level factors that could 

affect the size of local police forces—such as state-level differences in the 

amount of funding provided to local departments. Overall, the parameter 

estimates from our models indicate that each $25,000 in COPS hiring grant 

expenditures was associated with roughly an additional 0.6 officers in any 

given year.1

 With the exception of MORE grants, no other types of COPS 

grant expenditures were associated with increases in officers. 

Using the results from our regression models, we calculated for each year 

from 1994 through 2001 the number of sworn officers nationwide that 

would have been on the street absent the COPS expenditures in each year. 

The difference between this amount and the actual level of sworn officers 

yielded the number of officers due to COPS expenditures in a given year. 

The number of officers due to COPS increased from 84 in 1994 to 17,387 in 

2000, and then declined to 12,226 in 2001 (table 9). The increase and 

decrease in the number of officers due to COPS followed the pattern of 

COPS expenditures, which peaked in 2000 and then declined (see fig. 7 in 

app. III). Adding up the number of officers due to COPS in each year 

across the years from 1994 through 2001, we arrive at a total of about 

88,000 sworn officer-years due to COPS expenditures. 

From 1997 through 2000, when COPS expenditures neared or exceeded $1 

billion per year, we estimated that the expenditures led to increases in 

 1

Our estimate of the effect of COPS expenditures on officers is consistent with those in the 

research conducted by Evans and Owns, who used COPS hiring grants to estimate the 

relationship between changes in sworn officers and crime. They estimated that each 

$25,000 in COPS hiring grant expenditures produced an additional 0.7 of an officer in a 

given year. Evans and Owens, “Flypaper COPS,” 2005. 

Appendix IV: COPS Expenditures Led to 

Increases in Sworn Officers and Declines in 

Crime 

COPS Expenditures 

Led to Increases in 

Sworn Officers above 

Levels That Would 

Have Been Expected 

without Them and 

Were Responsible for 

about 88,000 OfficerYears 
Appendix IV: COPS Expenditures Led to 

Increases in Sworn Officers and Declines in 

Crime 

Page 59 GAO-06-104 Community Policing Grants 

sworn officers of between 2.4 percent and 2.9 percent above levels 

expected without them. In years prior to 1997, and in 2001, when COPS 

expenditures were lower, the percentage of officers due to COPS 

expenditures were lower than occurred from 1997 through 2000. 

Table 9: Estimated Effect of COPS Expenditures on the Number of Sworn Officers 

Nationwide in Each Year, 1994-2001 

Year 

Estimated number of officers 

due to COPS expenditures 

Percentage of total number of 

officers in the United States

1994 84 0.02%

1995 1,916 0.35%

1996 8,639 1.55%

1997 13,897 2.42%

1998 17,630 3.02%

1999 16,415 2.72%

2000 17,387 2.91%

2001 12,226 2.05%

Total, officer-yearsa 88,195 b 

Source: GAO analysis of Uniform Crime Report, Office of Justice Programs financial, Bureau of Economic Analysis, National Center for 

Health Statistics, and U.S. Census Bureau data. 

a

The total number of officer-years due to COPS expenditures is the sum of the number of officers due 

to COPS in each year. We call this total the number of officer-years due to COPS expenditures. It is 

not directly comparable with estimates of the number of sworn officers on the street as a result of 

COPS funds or with estimates of the number of officers funded by the COPS Office. 

b

Not applicable. 

An officer-year is the number of officers in a given year that were 

associated with COPS expenditures. According to this measure, an 

individual officer—or person—might be included in our counts of officers 

due to COPS in several years. Therefore, our estimate of the total number 

of officer-years arising from COPS expenditures is not equivalent to the 

number of officers that the COPS Office reportedly funded, nor does it 

represent an estimate of the total number of officers as a result of COPS 

grants. For a given year, however, our estimate represents the number of 

COPS-funded officers on the street. (For additional details on the methods 

we used to estimate the effects of COPS expenditures on officers, see 

app. VI.) 
Appendix IV: COPS Expenditures Led to 

Increases in Sworn Officers and Declines in 

Crime 

Page 60 GAO-06-104 Community Policing Grants 

In addition to our findings of the effects of COPS expenditures on the level 

of sworn officers, we found that Local Law Enforcement Block Grants 

expenditures also contributed to increases in officers above levels 

expected without them. Our finding about LLEBG grants effects on sworn 

officers is consistent with interview and survey responses reported by 

Urban Institute researchers in their evaluation of the implementation of 

the COPS program.2

 In their interviews with police chiefs, they found that 

the chiefs reported that they used LLEBG to supplement COPS funds. 

LLEBG grants could be used for a variety of purposes in addition to 

funding officers. 

Estimating the impact of COPS expenditures on changes in crime rates 

through their effects on the number of sworn officers, we found that COPS 

expenditures were associated with declines in crime rates for total, 

violent, and property crimes, as compared with their baseline levels in 

1993, the year prior to the distribution of COPS grants. The amounts of 

decline in crime rates varied among crime types and across years. The 

variation in the decline in crime rates in various crime types arose from 

our estimates of the effects of changes in officers on crime rates, and the 

variation over time within crime types arose from the variation in COPS 

expenditures. For example, for the total crime rate, we found that the 

impact of COPS peaked in 1998, as for that year, we estimated that COPS 

led to a reduction in the total crime rate of almost 1.4 percent from the 

level of crime in 1993. From 1999 and 2000, COPS expenditures of between 

$920 million and about $1 billion led to reductions in the total crime rate of 

about 1.3 percent, again, as compared with the 1993 level. In years prior to 

1998 and in 2001, when COPS expenditures were lower than their levels in 

1998 through 2000, the declines in total crime arising from COPS 

expenditures also were less than 1.3 percent (table 10). 

Similarly, for violent and property crimes, we found that the amount of 

decline associated with COPS expenditures varied from year to year, and 

for both of these crime categories, the largest decline in crime occurred 

during 1998. COPS expenditures led to a decline in violent crime of almost 

2.6 percent in 1998, compared with violent crime levels in 1993. For 1999 

and 2000, COPS expenditures led to about a reduction of about 2.4 percent 

in violent crime, from the 1993 level. For property crimes, the impact of 

 2

Roth, Jeffrey, et al. National Evaluation of the COPS Program, 2000. 

LLEBG Funds Also 

Contributed to Increases in 

Officer Strength 

COPS Expenditures 

Led to Reductions in 

Crime through 

Increases in Officers 
Appendix IV: COPS Expenditures Led to 

Increases in Sworn Officers and Declines in 

Crime 

Page 61 GAO-06-104 Community Policing Grants 

COPS expenditures from 1998 through 2000 was between 1.1 percent and 

1.2 percent, as compared to the 1993 level (table 10). 

Table 10: Estimated Percentage Change in Crime Rates from 1993 Levels Due to 

COPS Expenditures, 1994-2001, by Crime Type Category 

 Crime category 

Year Total crimes Violent crimes Property crimes

1994 –.01 –.01 –.01

1995 –.16 –.29 –.13

1996 –.70 –1.29 –.60

1997 –1.11 –2.05 –.95

1998 –1.39 –2.57 –1.19

1999 –1.28 –2.36 –1.10

2000 –1.34 –2.48 –1.15

2001 –0.93 –1.73 –.80

Source: GAO analysis of Uniform Crime Report, Office of Justice Programs financial, Bureau of Economic Analysis, National Center for 

Health Statistics, and U.S. Census Bureau data. 

Note: All estimates of the magnitude of the impact of COPS on crime are made with respect to the 

level of crime in 1993, the baseline year for our comparisons. The crime rates in 1993 in the data in 

our sample were as follows: the total crime rate was 5,904 per 100,000 persons; the violent crime 

rate was 846 per 100,000 persons; and the property crime rate was 5,058 per 100,000 persons. 

Our estimates of the impact of COPS expenditures on crime through their 

effects on the number of officers represent the effects of COPS 

expenditures on crime net of the effects of other factors that we controlled 

for in our model—including changes in economic conditions, population 

composition, and pre-COPS program trends in police agencies’ growth rate 

of sworn officers and growth rate in crime. By controlling for pre-COPS 

program growth rates in officers and crime, we made comparisons 

between agencies within population size categories that had similar 

growth rates in officers and crime but which differed on the timing and 

amount of COPS expenditures. In addition, through the use of state-byyear fixed effects, we controlled for state-level factors that could affect 

crime rates, such as changes in sentencing policy or state incarceration. 

As our estimates of the impact of COPS expenditures on crime come, in 

part, from our estimates of the effects of changes in officers on crime, we 

compared our estimates of the effect of changes in officers on changes in 

crime with estimates of these effects that appear in recent research. We 

found that each 1 percent increase in sworn officers was associated with 

about a 0.4 percent decline in total crime, about a 0.8 percent decline in 

violent crime, and a slightly less than 0.4 percent decline in property 
Appendix IV: COPS Expenditures Led to 

Increases in Sworn Officers and Declines in 

Crime 

Page 62 GAO-06-104 Community Policing Grants 

crime. Our estimates of this relationship—the elasticity of crime with 

respect to officers—is consistent with estimates that appear in recent 

literature of the effects of changes in police officers on changes in crime 

rates. Others report elasticities that are similar to ours. For example, in a 

study that used COPS granted officers to estimate the effect of increases in 

officers on crime, the authors reported an estimated elasticity for violent 

crime of –0.99 (a 1 percent increase in officers led to a 0.99 percent decline 

in violent crimes) and a property crime elasticity of –0.26.3

 In another 

paper that used electoral cycles to estimate the effect of increases in 

officers on crime, the author provides a set of elasticities under different 

model specifications.4

 The elasticity for property crimes was calculated to 

be about –0.3, and the elasticity for violent crimes was about –1.0. (See 

app. VI for more information on the methods that we used to calculate our 

elasticities and to estimate the impact of COPS expenditures on crime.) 

While we found that COPS expenditures were associated with reductions 

in total crime and the violent and property crime categories, when we 

examined the effects of COPS expenditures on specific types of index 

crimes, we found significant reductions in murder, robbery, aggravated 

assault, burglary, and motor vehicle theft. We found a negative association 

between COPS expenditures and larceny, but this effect was not 

statistically significant. Finally, we found a positive but statistically 

insignificant association between COPS expenditures and rape. (See table 

17 in app. VI.) 

Additionally, for agencies that served populations of 10,000 or more 

persons, we found that the effects of COPS expenditures on the total 

crime rate were consistent across agencies that served populations of 

varying sizes with the exception of agencies that served populations of 

between 25,000 and 50,000 persons. The magnitude of the effects tended to 

increase with the size of agencies, where agency size refers to the 

population served by the agency. In general, as the size of agencies 

 3

Evans and Owens, “Flypaper COPS,” 2005. 

4

Levitt, Steven D. “Using Electoral Cycles in Police Hiring to Estimate the Effect of Police 

on Crime: Reply” American Economic Review, September 2002, 92(4), pp. 1244-50. Justin 

McCrary found that Levitt’s original estimates of the effect of officers on crime suffered 

from a computation error. Levitt was able to confirm his results after correcting the error 

using an alternative instrument. See McCrary, Justin, “Do Electoral Cycles in Police Hiring 

Really Help Us Estimate the Effect of Police on Crime: Comment.” American Economic 

Review. June 2002, 92(4), pp. 1236-43. 

Various Specifications of 

Our Regressions Yielded 

Consistent Findings about 

the Effect of COPS 

Expenditures on Crime 
Appendix IV: COPS Expenditures Led to 

Increases in Sworn Officers and Declines in 

Crime 

Page 63 GAO-06-104 Community Policing Grants 

increased, we found that the impact of COPS expenditures on the total 

crime rate also increased. For agencies serving populations between 

25,000 and 50,000, we observed a negative relationship between COPS 

expenditures and crime. However, the estimated effect was not 

statistically significant. (See table 18 in app. VI.) 

As there are uncertainties associated with formulated regression models, 

and point estimates derived from a single regression model can give 

misleading information, we estimated our regressions under different 

assumptions about how COPS expenditures could affect crime. Under the 

various models, we introduced lagged effects, nonlinear effects for COPS 

hiring grants, and effects for the year of receipt of COPS grants—to test 

whether the impact of COPS occurred in the years in which the money 

was spent. From the various specifications, we estimated the elasticity of 

crime with respect to officers. We found that the elasticity for total crimes 

ranged from –0.41 to –0.95. The elasticity that we used to calculate the 

impact of COPS on the decline in index crimes was –0.42, which is at the 

lower end of the range of elasticities that we estimated. Therefore, under 

assumptions different from the preferred specification about how COPS 

expenditures are related to officers and crime, we would arrive at a larger 

estimated impact of COPS on the decline in crime than we report above. 

Also, under the varying assumptions about how COPS expenditures are 

related to crime, we estimated elasticities of violent crimes with respect to 

officers and elasticities of property crimes with respect to officers. For 

violent crimes, the elasticities derived from these regressions ranged from 

–0.76 to –1.8. The elasticity that we used to estimate the impact of COPS 

on the decline in violent crimes was –0.8. This elasticity is at the lower end 

of the range of elasticities that we estimated, which implies that the 

impacts of COPS on violent crimes could be larger than the impacts that 

we reported. For property crimes, the range of estimated elasticities was 

from –0.35 to –0.80. (See table 20 in app. VI.) 

In addition to our findings of the effects of COPS expenditures on crime, 

we found that LLEBG expenditures were consistently associated with 

declines in total crime rates and declines in the murder, rape, robbery, 

aggravated assault, burglary, and larceny crime rates. Only for motor 

vehicle theft did we not find a significant effect of LLEBG expenditures. 

However, because LLEBG grant funds are related to the levels of violent 

crime occurring within a jurisdiction, the relationship between LLEBG 
Appendix IV: COPS Expenditures Led to 

Increases in Sworn Officers and Declines in 

Crime 

Page 64 GAO-06-104 Community Policing Grants 

expenditures and crime may be one of bidirectional causality.5 By this, we 

mean because LLEBG grant amounts were determined in part on the levels 

of violent crime, violent crime in a community can be construed as a cause 

of LLEBG grants in addition to an effect of having received them. (See 

table 17 in app. VI.) 

The decline in crimes attributable to COPS expenditures accounted for at 

most about 10 percent of the total drop in crime from 1993 to 1998, and 

about 5 percent of the drop from 1993 to 2000. Therefore, various factors 

other than COPS expenditures were responsible for the majority of the 

total decline in crime during the 1990s. While in our regression models of 

the effects of COPS funds on crime, we were able to control for the effects 

of many factors that could be related to the decline in crime, we did not 

attempt to estimate the amount that each of these factors individually had 

contributed to the overall drop in crime.6

 Rather, by isolating the amount 

by which crime rates declined because of COPS and comparing that 

amount with the total decline in crime from our 1993 baseline year, we 

calculated COPS contribution to the overall decline in crime. The amount 

of the total drop in crime not associated with COPS expenditures reflects 

the amount due to factors other than COPS. 

While COPS’ contributions to the decline in crime rates did not account 

for the majority of the total drop in crime rates, the amounts of declines in 

crime rates attributable to COPS were on the same order of magnitude as 

were COPS expenditures’ contributions to local law enforcement 

expenditures for police. From 1994 through 2001, COPS expenditures 

amounted to slightly more than 1 percent of total local expenditures for 

 5

According to officials at the Bureau of Justice Statistics, the formula for determining 

LLEBG grant amounts is based in part upon the level of violent crime occurring within a 

jurisdiction. By comparison, there was no requirement for COPS funding to be related to 

violent crime. Therefore, without an instrument to isolate the relationship between LLEBG 

expenditures and crime rates, we cannot conclude that the estimated effects of LLEBG 

expenditures on crime would hold if we were able to isolate statistically the causal 

direction of effects. 

6

Some of the factors associated with the crime drop have been discussed in Blumstein and 

Wallman (2002). See Blumstein, A., and J. Wallman (eds.), The Crime Drop in America, 

Cambridge, United Kingdom: Cambridge University Press, 2000. 

Factors other than COPS 

Expenditures Contributed 

Larger Amounts to the 

Reduction in Crimes, but 

COPS Contribution Was in 

Line with COPS 

Expenditures 
Appendix IV: COPS Expenditures Led to 

Increases in Sworn Officers and Declines in 

Crime 

Page 65 GAO-06-104 Community Policing Grants 

police services nationwide. As we found and reported, COPS expenditures 

were responsible for about a 1.4 percent decline in the total crime rate. 
Appendix V: COPS Expenditures Associated 

with Policing Practices That Crime Literature 

Indicates Are Effective in Preventing Crime 

Page 66 GAO-06-104 Community Policing Grants 

This appendix addresses our third reporting objective: determining the 

extent to which COPS grant expenditures during the 1990s were 

associated with police departments adopting policing activities or 

practices that the crime literature indicates could contribute to reductions 

in crime. Specifically, it describes the results of our analyses of the 

relationships between COPS grant expenditures and changes in policing 

practices reported in two surveys of local law enforcement agencies, and it 

summarizes our assessment of studies that conducted systematic reviews 

of research on the effectiveness of various policing practices. Our analysis 

of the first of the two surveys of policing practices compares changes in 

reported policing practices between 1993 and 1997, that is, prior to the 

distribution of COPS grants and after many COPS grants had been 

distributed. In our analysis of the second survey, we compare changes 

from 1996 to 2000, or during the implementation COPS program. In 

addition, we provide a limited summary of our analysis of systematic 

reviews of evaluations of policing practices that could contribute to 

reductions in crime. (See app. VII for the details related to our 

methodology for analyzing policing practices.) 

Prior to the implementation of COPS grants, many local law enforcement 

agencies had adopted a number of problem-solving, place-oriented, crime 

analysis, and community collaboration policing practices. Problem-solving 

practices refer to efforts by the police to focus on specific problems and 

tailor their strategies to the identified problems. Place-oriented practices 

include attempts to identify the locations where crime repeatedly occurs 

and to implement procedures to disrupt these recurrences of crime. Crime 

analysis includes the use of tools such as geographic information systems 

to identify crime patterns. Community collaboration includes attempts to 

improve or enhance citizen feedback about crime problems and the 

effectiveness of policing efforts to address them. 

Our analysis of the Policing Strategies Survey data for 1993—the year 

before COPS grants were distributed—indicates that surveyed agencies 

that received a COPS grant between 1994 and 1997 reported higher mean 

levels of the above policing practices than agencies that did not receive a 

COPS grant between 1994 and 1997. For example, in 1993, the mean 

number of all practices reported by grantee agencies was about 13 out of a 

possible 38 practices, while the mean number of all practices reported by 

nongrantee agencies was about 11 practices. However, among the 

agencies that received a COPS grant between 1994 and 1997, there were 

larger increases in the mean level of all reported practices between 1993 

and 1997 except for those related to crime analysis. COPS grantee 

Appendix V: COPS Expenditures Associated 

with Policing Practices That Crime Literature 

Indicates Are Effective in Preventing Crime 

Comparisons of Preand Within-COPS 

Grant Program Levels 

of Reported Policing 

Practices Show That 

COPS Grantee 

Agencies Reported 

Larger Increases than 

Non-COPS Agencies 
Appendix V: COPS Expenditures Associated 

with Policing Practices That Crime Literature 

Indicates Are Effective in Preventing Crime 

Page 67 GAO-06-104 Community Policing Grants 

agencies reported in 1997 an increase of about 3.5 practices overall, as 

compared with a mean increase of less than 2 practices by the agencies 

that did not receive COPS grants during this period. The largest 

differences between COPS grantees and nongrantee agencies in the 

reported increase in practices occurred for the problem-solving and placeoriented practices (table 11). 

Table 11: Mean Levels of Policing Practices in 1993 and 1997, by Category of Policing Practices and whether Agencies 

Received a COPS Grant between 1994 and 1997 

 COPS grantee agencies 

Agencies that did not 

receive a COPS grant 

Category of 

policing practice 1993 1997 Difference 1993 1997 Difference

Problem solving 4.57 5.80 1.24 4.16 4.68 0.52

Place oriented 2.98 4.21 1.23 2.38 2.84 0.47

Community collaboration 3.48 4.41 0.93 2.69 3.45 0.76

Crime analysis 1.88 1.93 0.05 1.66 1.71 0.05

Total 12.90 16.34 3.44 10.89 12.69 1.80

Source: GAO Analysis of Policing Strategies Survey, Office of Justice Programs financial, Bureau of Economic Analysis, National

Center for Health Statistics, U.S. Census Bureau, and Uniform Crime Report data. 

From a series of regression models of the effects of COPS grants on 

changes in policing practices, we found that both the receipt of a COPS 

grant, and the amount of per capita COPS expenditures by agencies were 

associated with increases in the levels of reported policing practices 

between 1993 and 1997. Our regressions control for the underlying trend in 

the reported use of policing practices, for differences in agency 

characteristics that could be associated with increases in reported levels 

of policing practices—such as the size of the jurisdiction—and changes in 

the economic and social characteristics of the county in which the agency 

was located. We estimated separate regressions of the effect of the receipt 

of a COPS grant and of the cumulative per capita amount of COPS 

expenditures on the levels of reported policing practices. 

Our regression models for estimating the effects of receipt of a COPS grant 

on the change in police practices between 1993 and 1997 show that 

agencies that received at least one COPS grant had significantly larger 

changes in the overall number of practices than did agencies that did not 

receive a COPS grant during this period. Specifically, according to our 

analysis of the survey data, the average number of practices increased by 

2.9 over this period, and the receipt of a COPS grant accounted for 1.8 of 

this reported increase. Further, when we examined our results from 
Appendix V: COPS Expenditures Associated 

with Policing Practices That Crime Literature 

Indicates Are Effective in Preventing Crime 

Page 68 GAO-06-104 Community Policing Grants 

separate regressions for the different categories of practices, we found 

that receipt of a COPS grant was associated with significant increases in 

reported levels of problem-solving and place-oriented practices, but was 

not related to changes in community collaboration or crime analysis 

practices. (See app. VII for details.) 

Our regression models further show that changes in practices were also 

associated with the cumulative amount of per capita spending on COPS 

grants. All other things being equal, a $1 increase in per capita spending 

was associated with an increase of 0.23 policing practices. As we found for 

the effects of the receipt of a grant on changes in police practices, these 

regressions also showed that the level of per capita spending on COPS 

grants was significantly associated with increases in problem-solving and 

place-oriented practices. However, per capita spending on COPS grants 

was also associated with increases in crime analysis practices. (See app. 

VII for details.) 

Receipt of a COPS grant was associated with increases in the overall 

adoption of policing practices among agencies serving populations of 

different sizes. Regardless of the size of populations served, agencies that 

received COPS grants adopted almost twice as many practices between 

1993 and 1997 as agencies that did not receive COPS grants. However, in 

both years, agencies serving larger populations also reported higher mean 

levels of policing practices (table 12 and fig. 9). 

Table 12: Mean Levels of Policing Practices in 1993 and 1997, by Size of Agency and whether Agencies Received a COPS 

Grant between 1994 and 1997 

 COPS grantee agencies 

Agencies that did not 

receive a COPS grant 

Jurisdiction population (number of 

persons) 1993 1997 Difference 1993 1997 Difference

10,000 to fewer than 50,000 11.87 15.14 3.27 10.12 11.80 1.68

50,000 to 150,000 14.58 18.70 4.12 14.40 16.81 2.41

More than 150,000 19.30 22.82 3.52 19.00 20.91 1.91

Source: GAO Analysis of Policing Strategies Survey and Office of Justice Programs financial data. 

The Effects of COPS 

Grants on Agencies’ 

Reported Increases in 

Policing Practices Differed 

across Agencies Serving 

Populations of Different 

Sizes 
Appendix V: COPS Expenditures Associated 

with Policing Practices That Crime Literature 

Indicates Are Effective in Preventing Crime 

Page 69 GAO-06-104 Community Policing Grants 

Figure 9: Reported Levels of Policing Practices in 1993 and 1997 in Agencies That 

Received and Did Not Receive COPS Grants, by Size of Population Served 

Our regressions of the effect of COPS expenditures on changes in reported 

levels of policing practices between 1993 and 1997, indicate, however, that 

the effects of receiving a COPS grant were larger in agencies in 

jurisdictions serving fewer than 50,000 persons and in jurisdictions serving 

more than 150,000 persons, than in agencies in jurisdictions serving 

populations of between 50,000 and 150,000 persons. 

Our analysis of the National Evaluation of COPS Survey data on policing 

practices in 1996 and in 2000 also showed that agencies that received 

COPS grants reported larger increases in the mean level of policing 

practices than did non-COPS grantee agencies, but that the effects were 

not statistically significant. The findings suggest that there was no 

continued overall increase in reported policing practices in the period 

from 1996 to 2000. 

Regardless of when agencies received COPS grants and made COPS 

expenditures, we found that COPS grantee agencies reported larger 

increases in policing practices between 1996 and 2000 than did the 

agencies that did not have COPS grants in these years. For example, for 

the agencies that received their first COPS grant in 1996 or before, the 

average increase in reported use of policing practices from 1996 to 2000 

was about 21 percent, and for the agencies that made COPS grant 

Reported Levels of 

Policing Practices 

among COPS 

Grantees Did Not 

Increase Overall from 

1996 to 2000 

Problem-solving: COPS grantee

Problem-solving: Non-COPS agency

Source: GAO analysis of Policing Strategies Survey and Office of Justice Programs financial data.

Place-oriented: COPS grantee

Place-oriented: Non-COPS agency

Mean number of policing practices

1993 1997

Calendar year

0

1

2

3

4

5

6

7
Appendix V: COPS Expenditures Associated 

with Policing Practices That Crime Literature 

Indicates Are Effective in Preventing Crime 

Page 70 GAO-06-104 Community Policing Grants 

expenditures after 1996, the average increase in reported use of policing 

practices was about 17 percent. By contrast, for the agencies that had not 

made any COPS grant expenditures by 2000, there was about a 0.2 percent 

decrease in the reported use of policing practices from 1996 to 2000, and 

for the agencies that did not make any COPS grant expenditures after 

1996, there was about a 3 percent increase in the reported use of policing 

practices from 1996 to 2000 (table 13). 

Table 13: Difference in Mean Levels of Reported Policing Practices in 1996 and 2000, by Category of Policing Practices and 

Timing of COPS Grant Expenditures 

Made COPS 

expenditures 

after 1996 

Made COPS 

expenditures in 1996 

or before 

Did not make COPS 

expenditures after 1996 

Did not make COPS 

expenditures between 

1994 and 2000 

Category of policing 

practice 

1996 Change 1996 Change 1996 Change 1996 Change

Problem solving and 

place oriented 6.09 1.00 6.08 1.45 6.91 0.11 7.08 -0.13

Community 

collaboration 

3.36 0.53 3.42 0.56 3.28 0.47 3.33 0.38

Crime analysis 1.67 0.32 1.70 0.39 1.87 -0.20 1.88 -0.26

Total 11.12 1.86 11.21 2.38 12.06 0.38 12.30 -0.02

Source: GAO analysis of National Evaluation of COPS Survey and Office of Justice Programs financial data. 

Although we observed larger average increases in reported policing 

practices among agencies that spent COPS grant funds than among 

agencies that did not spend COPS grant funds, when we controlled for 

underlying trends in the reported adoption of policing practices and 

agency characteristics, we found that changes in per capita COPS 

expenditures made between the period preceding wave 1 of the survey 

(1994 through 1996) and the period following wave 1 of the survey (1997 

through 2000) were not associated with changes in reported overall 

policing practices between 1996 and 2000 (app. VII). This suggests that 

there was no continued overall increase in reported policing practices in 

the period from 1996 to 2000, as a function of COPS grant expenditures. 

Our analysis of six systematic reviews of evaluations of the effectiveness 

of various policing practices in preventing crime indicates that the current 

evidence ranges from moderate to strong that problem-oriented policing 

practices and place-oriented practices are either effective or promising as 

strategies for addressing crime problems. For example, problem-oriented 

approaches that focus on criminogenic substances such as guns and drugs 

Crime Literature 

Provides Evidence for 

Effectiveness of Some 

Policing Practices 
Appendix V: COPS Expenditures Associated 

with Policing Practices That Crime Literature 

Indicates Are Effective in Preventing Crime 

Page 71 GAO-06-104 Community Policing Grants 

appear to be effective in reducing both violent and property crimes. And 

hot spots approaches—place-oriented approaches that temporarily apply 

police resources to discrete locations where crime is concentrated at 

much higher rates than occur jurisdictionwide—have also been found to 

be effective in reducing crime. However, the magnitudes of the effects of 

these interventions are difficult to estimate, especially on citywide crime 

rates, as the interventions that were reviewed as effective generally were 

concentrated in comparatively small places. Further, the enduring nature 

of these interventions is not fully understood. It is not known, for example, 

how long the effects of a problem- or place-oriented intervention persist. 

In addition, some of the reviews point out that research designs 

undertaken to date make it difficult to disentangle the effects of problemoriented policing from hot spots policing. There is suggestive, but limited, 

evidence that the combination of these practices may be more effective in 

preventing or reducing crime than any one strategy alone. 

In contrast to the findings on problem-oriented and place-oriented policing 

practices, there is little evidence in the literature for the effectiveness of 

community collaboration practices—such as increasing foot patrol, 

establishing community partnerships, and encouraging citizen 

involvement—in reducing or preventing crime. 
Appendix VI: Methods Used to Estimate the 

Effects of COPS Funds on Officers and Crime 

Page 72 GAO-06-104 Community Policing Grants 

In this appendix, we describe the methods we used to address our 

reporting objective regarding the impacts of the COPS funds on officers 

and crime: determining (1) the extent to which COPS grant expenditures 

contributed to increases in the number of sworn officers in police agencies 

in the 1990s and (2) the extent to which COPS expenditures contributed to 

declines in crime in the 1990s through their effects, if any, on officers. 

In examining the effect of COPS funds on crime, we estimate the impacts 

of the funds on crime through their impacts on officers. The effect of 

police on crime has a theoretical basis in the economics literature. 

Economic models posit that criminals weigh the gains from criminal 

activity against its costs—the possibility of arrest and incarceration. 

Anything that increases the probability of arrest, such as additional police, 

will thus deter criminal activity; we might call this the deterrence effect. A 

second effect stems from arrests directly. If criminals are arrested and 

incarcerated, they will not be able to commit street crimes; we might call 

this the incapacitation effect. 

The relationship between police and crime has been studied empirically, 

with mixed results. Several reviews of research that investigated this 

relationship have reported that a minority of papers find a significant 

negative relationship between increases in the number of officers and 

crime.1

 However, these reviews also point out that many of the studies 

have methodological flaws. In a report to Congress on what works in 

crime prevention, Lawrence Sherman and others drew upon a limited body 

of research that addressed the methodological concerns and concluded 

that increases in the number of police officers work to prevent crime.2

One of the major methodological issues associated with estimating the 

relationship between police officers and crime is the issue of reverse 

causality. This issue revolves around determining how to disentangle the 

relationship between the number of police officers and crime, as 

 1

For example, see: Marvell, Thomas, and Carlisle Moody. “Specification Problems, Police 

Levels, and Crime Rates,” Criminology 1996, 34. pp. 609-46. Eck, John, and Edward 

Maguire, 2000. “Have Changes in Policing Reduced Violent Crime? An Assessment of the 

Evidence.” in A. Blumstein and J. Wallman, eds., The Crime Drop in America. New York: 

Cambridge University Press, 2000. pp 207-65. 

2

Sherman, Lawrence, 1998. “Policing for Crime Prevention,” in Sherman, L., et al. (eds.) 

Preventing Crime: What Works, What Doesn’t, What’s Promising: A Report to the United 

States Congress. Washington, D.C.: National Institute of Justice, Chapter 8. 

Appendix VI: Methods Used to Estimate the 

Effects of COPS Funds on Officers and Crime

Prior Literature on the 

Relationship between 

Officers and Crime 

Addresses Issues 

Relating to Estimating 

the Effects of COPS 

Funds on Crime 
Appendix VI: Methods Used to Estimate the 

Effects of COPS Funds on Officers and Crime 

Page 73 GAO-06-104 Community Policing Grants 

municipalities having higher crime rates generally also have more officers. 

For example, Detroit has twice as many police per capita as Omaha and 

four times the violent crime rate, but it would be incorrect to conclude 

that the additional officers in Detroit were the cause of its higher crime 

rate than Omaha’s.3

 By simply comparing a municipality’s police force and 

crime rate to those in other municipalities, one would incorrectly infer 

that Detroit’s higher crime rate was caused by its additional police 

officers. 

Repeated observations on crime and police in a locality lead to a more 

robust research design by controlling for the time-invariant differences in 

rates of crime and police between areas. This is done by introducing fixed 

effects into regression models. Using this approach, the question that the 

analysis attempts to address becomes: Do we see the crime rate fall as the 

number of police rises? By controlling for the “baseline” crime rates in 

different areas, some researchers have estimated a negative relationship 

between police and crime.4

However, if the rise in the number of police in a locality is a response to 

increasing crime rates, including fixed effects does not resolve the issue of 

reverse causality raised by the Detroit example. A next step is to introduce 

an instrument—for example, a variable that affects the size of the police 

force but that, given this size, does not affect crime. In one study, the 

researcher made use of the fact that the size of a police force increases 

before an election. If the only way that crime is affected by the election is 

through the number of police, then this approach can be used to estimate 

the relationship between crime and police. In this study, the researcher 

found that crime fell in several index categories before an election.5

A series of more recent papers that used instruments found a negative 

relationship between police and crime. Two studies used an increase in 

 3

Levitt, Steven D. “Using Electoral Cycles in Police Hiring to Help Estimate the Effect of 

Police on Crime.” American Economic Review, 87 (1997): 270-290. 

4

See, for example, Levitt (1997) and Marvel and Moody (1996). 

5

McCrary (2002) found that Levitt’s estimation of standard errors suffered from a 

computational error. Levitt (2002) was able to confirm his results when the error was 

corrected by using an alternative instrument—the number of municipal workers and 

firemen. McCrary, Justin. “Using Electoral Cycles in Police Hiring to Estimate the Effect of 

Police on Crime: Comment.” American Economic Review. June 2002, 92(4), pp. 1236-43. 

Levitt, Steven D. “Using Electoral Cycles in Police Hiring to Estimate the Effects of Police 

on Crime: Reply” American Economic Review, September 2002, 92(4), pp. 1244-50. 
Appendix VI: Methods Used to Estimate the 

Effects of COPS Funds on Officers and Crime 

Page 74 GAO-06-104 Community Policing Grants 

police presence because of a terrorist alert and showed declines in 

nonterrorist-related crimes within a single city. In a study of Buenos Aires, 

the researchers found that police stationed in response to a terrorist threat 

on Jewish centers caused a decline in automobile theft.6

 In another paper, 

the researchers showed that crime fell in Washington, D.C., on days when 

the Department of Homeland Security increased the terror alert level.7

 At 

the national level, researchers at the University of Maryland used the 

number of police officers granted through the COPS program as an 

instrument for the actual number of police and estimated negative 

relationships between increases in police officers and crime.8

We adopted a two-stage approach to estimating the effects of COPS 

expenditures on crime. Much as the University of Maryland researchers 

did, we used COPS funds as a source of variation to explain officers. 

However, while the University of Maryland researchers used officers 

granted by COPS funds, we used COPS expenditure amounts—the actual 

COPS dollars spent by agencies in given years—as the source of variation. 

We began with an analysis of the “first stage” and tested whether COPS 

funds had an effect on the number of officers. To the extent that hiring 

funds affected the number of police but did not affect crime in any other 

way, these funds would be a valid instrument for estimating the effect of 

officers on crime. We then estimated the “reduced form,” or the 

relationship between COPS expenditures and crime. Using parameters 

estimated from these regressions, we are able to calculate the relationship 

between police and crime. 

This approach has limitations, however. For example, we learn very little 

about how agencies operate. If agencies were to use the additional officers 

to employ different police tactics, and were able to reduce crime, we 

would be unable to say whether it was the increase in officer numbers or 

tactics that was the true cause of the decrease. Thus, we would be unable 

 6

Di Tella, Rafael, and Ernesto Schargrodsky. “Do Police Reduce Crime? Estimates Using 

the Allocation of Police Forces after a Terrorist Attack.” American Economic Review. 

March 2004, 94(1). pp. 115-133. 

7

Klick, Jonathan, and Alexander Tabarrok. “Using Terror Alert Levels to Estimate the 

Effect of Police on Crime.” Journal of Law and Economics, April 2005, vol. XLVIII. 

8

Evans, William N., and Emily Owens. “Flypaper COPS,” College Park, Maryland: University 

of Maryland. Available online 

www.bsos.umd.edu/econ/evans/wpapers/Flypaper%20COPS.pdf, 2005. 

Our Approach to 

Estimating the Effects 

of COPS 

Expenditures on 

Officers and Crime 
Appendix VI: Methods Used to Estimate the 

Effects of COPS Funds on Officers and Crime 

Page 75 GAO-06-104 Community Policing Grants 

to contribute to the question of whether increases in officer strength are 

either necessary or sufficient to reduce crime, without a change in police 

tactics. 

A second concern is that agencies that were more likely to take initiative 

in applying for and receiving COPS grants might be those that were also 

more effective in preventing crime. These agencies might also be those 

that achieved larger or more rapid declines in crime. If this were the case, 

we might incorrectly associate declines in crime with COPS grant 

expenditures because of other possible factors. To assess this potential, 

we estimated a regression that predicted whether an agency spent COPS 

funds in a given year from 1994 through 2001 based on demographic 

characteristics, economic conditions, and lagged property and violent 

crime rates. From the regressions, we predicted the probability of 

spending COPS grant funds—or the propensity of agencies to spend COPS 

funds. Whether or not an agency actually spent COPS funds, it received a 

propensity score, based upon the values of its characteristics in the model 

that predicated the probability of spending COPS funds. Agencies that 

actually spent COPS funds can then be compared to similar agencies—

those with similar propensity scores—that did not spend COPS funds. We 

grouped agencies into five categories based on their propensity scores. 

Within each of these five categories, we compared the patterns of violent 

crime rates and property crime rates between the agencies that spent 

COPS funds and those that did not spend them. Our analysis showed that 

within these groupings of agencies having similar propensity scores, the 

agencies that actually spent COPS funds generally had larger declines in 

crime rates than did those that did not spend COPS funds. 

Another question is whether a drop in a specific crime type, such as 

automobile theft, in a certain locality is a net gain for society as a whole. 

For example, the rationality of criminals may lead them to respond to an 

increase in the number of police by moving to an area with fewer police or 

switching to a different type of crime.9

 In addition, there is the possibility 

that an increase in the number of police increases the reporting rate of 

crimes, and not the crimes themselves.10 This possibility, however, would 

 9

Cook, Philip, “The Clearance Rate as a Measure of Criminal Justice System Effectiveness,” 

Journal of Public Economics, Vol. 11, 1979, pp. 135-142. 

10Swimmer, Eugene, “The Relationship of Police and Crime: Some Methodological and 

Empirical Results,” Criminology, Vol. 12, 1974: pp. 293-314. 
Appendix VI: Methods Used to Estimate the 

Effects of COPS Funds on Officers and Crime 

Page 76 GAO-06-104 Community Policing Grants 

lead us to underestimate the effects of COPS funds on crime, as discussed 

in appendix I. 

Our main specification estimated the effect of COPS funds on officers, 

using the following control variables: 

(1) POLICEit = β1

HIREit+ β2MOREit+ β3INNOVit+ β4MISCit + β5BYRNEDISit + 

β6

LLEBGit + β7NONCOPSit + γXit + αi + αt + αst + (quartile of prior growth 

rates) * (population stratification) * year 

Where 

• POLICEit is the dependent variable, the sworn officers per 10,000 in 

population in agency i in year t; 

• HIREit is the amount of money paid in Hiring grants; and 

• MOREit are COPS MORE grants; INNOVit are COPS grants for 

innovative policing, and MISCit refers to the remaining types of COPS 

grants; all are expressed as expenditure in per capita amounts. 

• BYRNEDISit are Byrne discretionary grant expenditures,11 LLEBGit are 

LLEBG grant amounts, and NONCOPSit are all other federal non-COPS 

law enforcement grants; all are expressed in per capita amounts. We 

introduce these variables to control for other federal funds. 

• Xit contains a number of demographic and economic control variables, 

including local employment rates, per capita income, and population 

composition variables that measured the percentage of population 15 

to 24 years old and the percentage of the population that was nonwhite. 

The economic and demographic controls were measured at the level of 

 11Because Byrne formula grants are passed through states to local agencies and the 

methods to track the amount of Byrne dollars going to local agencies are unreliable, we 

were unable to include Byrne formula grant amounts in our models. Moreover, according 

to an Abt Associates evaluation of Byrne formula grants, about 40 percent of the amounts 

passed through the states to local law enforcement agencies went to multijurisdictional 

task forces, thereby further complicating the task of tracking Byrne discretionary grant 

expenditures to local law enforcement agencies. See Dunworth, Terence, and Aaron J. 

Saiger, National Assessment of the Byrne Formula Grant Program: Where the Money 

Went—An Analysis of State Subgrant Funding Decisions Under the Byrne Formula 

Grant Program, Report 1, Washington, D.C.: National Institute of Justice Research Report, 

December 1996. 

Model of the Effect of 

COPS Expenditures on the 

Number of Police Officers 
Appendix VI: Methods Used to Estimate the 

Effects of COPS Funds on Officers and Crime 

Page 77 GAO-06-104 Community Policing Grants 

the county within which a particular agency was located. The 

parameters for these variables are represented by γ.

We included state-by-year fixed effects—represented by αst—to correct for 

changes in crime policy at the state level, such as changes in the number 

incarcerated and changes in sentencing policy. We included agency fixed 

effects—represented by αi

—to capture time invariant differences across 

agencies, and time fixed effects—represented by αt

—to capture changes 

affecting the entire nation. 

Because of how the money was distributed, there may be some concern 

that our estimate of the effect of the COPS money on officers is biased. 

For example, it might be that agencies that received a disproportionate 

share of the money relative to their populations had the benefit of 

preexisting positive growth of numbers of officers, in addition to possible 

declines in crime. If the trends continued, we might be incorrectly 

associating increases in officers or decreases in crime with the amount of 

COPS money received, rather than these preexisting trends. 

To address this concern, we separated the agencies into four groups, 

based on the growth rate in both officers and crime during 1990–1993, 

when the COPS program was introduced. We constructed each 

combination of these groups, producing 16 cells. These cells were then 

“interacted” with each year and four population categories, for a total of 

768 effects. In essence, each agency was compared with another agency 

that had a similar “trajectory” of crime and officers in the pre-COPS 

period.12 These growth trends are represented by the (quartile of prior 

growth rates) expression in equation (1). 

Finally, to obtain estimates of the effects of COPS expenditures on officers 

relative to the average person in the United States, we estimated weighted 

regressions where the weights were the population served by an agency. 

Because of these effects, the parameters of interest, β1

 though β4, are the 

effect of the COPS funds once other federal funds, demographic and 

economic conditions, time and agency fixed effects, and these “growth 

rate” effects are controlled for. 

 12This approach was proposed by Evans and Owens (2005). 
Appendix VI: Methods Used to Estimate the 

Effects of COPS Funds on Officers and Crime 

Page 78 GAO-06-104 Community Policing Grants 

As with our methodology in estimating the effect of COPS funds on 

officers, we estimate the effect of COPS funds on crime. Our main 

specification used the following controls in the following equation: 

(2) CRIMEit = μ1

HIREit + μ2MOREit + μ3INNOVit+ μ4MISCit + μ5BRYNEDISit + 

μ6

LLEBGit + μ7NONCOPSit + πXit + δi + δt + δst + (quartile of prior growth 

rates) * (population stratification) * year 

The independent variables are identical to those defined for equation (1). 

The dependent variable (CRIMEit) is the UCR total—or index—crime rate. 

We also estimate separate equations for the crime rates of components of 

the crime index: murder and non-negligent manslaughter, forcible rape, 

robbery, aggravated assault, burglary, larceny theft, and motor vehicle 

theft.13 Again, the parameters of interest are μ1

 through μ4. 

As in equation (1), the economic and demographic covariates in equation 

(2) are represented by Xit; δi

, δt, and δst represent the agency, year, and 

state-times-year fixed effects; and we also include the pre-1993 growth rate 

variables. 

Unlike the other COPS grant types, COPS hiring grants were to be used 

specifically for hiring officers. Consequently, variation in the number of 

officers coming from COPS hiring grants should be unrelated to other 

changes in police expenditures. In this sense, it may be a valid instrument 

for officers. 

Using the coefficients of officers in equations (1) and (2), we calculated an 

estimate of the change in crime with respect to change in officers: (μ1

/β1), 

μ1

 and β1 are the coefficients from equations (1) and (2). 

The elasticity is a measure of the percentage change in crime derived from 

a percentage change in police. We used coefficients of officers in 

equations (1) and (2) to calculate an estimate of the elasticity of crime 

with respect to officers in 1993: 

(3) ELASTICITY = (μ1

 / β1)*(POLICE1993/CRIME1993) 

 13We excluded arson from our analysis, because of limited reporting of this crime to the 

UCR, as indicated by the FBI. (See app. I.) 

Model of the Effect of 

COPS Expenditures on 

Crime 

The Implied Relationship 

between Police Officers 

and Crime 
Appendix VI: Methods Used to Estimate the 

Effects of COPS Funds on Officers and Crime 

Page 79 GAO-06-104 Community Policing Grants 

where 

• μ1 and β1 are the coefficients from equations (1) and (2) and 

• POLICE1993 and CRIME1993 are average police strength and crime rates for 

1993. 

To test the robustness of our estimates under different assumptions about 

how COPS grant expenditures are related to officers and crime, we 

estimated the elasticity of crime with respect to officers under a number of 

different specifications, as described in table 14. 

Table 14: Alternate Specifications of the Relationship between COPS Expenditures 

and Crime 

Variable in specification 1 2 3 4 5 

MORE, Innovative, and Miscellaneous COPS expenditures x x x 

LLEBG, Byrne discretionary, and other federal non-COPS 

expenditures 

x x x 

“Got grant” specification x 

Lagged values of MORE, Innovative, and Miscellaneous COPS 

expenditures 

 x x 

Lagged values of LLEBG, Byrne discretionary, and other federal 

non-COPS expenditures 

 x x 

Demographic and economic controls x x x x x 

Growth rate cells x x x 

Lagged value of Hiring grant expenditures x 

Quadratic term for Hiring grant expenditures x 

State by year fixed effects x x x x 

Source: GAO analysis. 

Note: An X indicates that a variable was included in a specification. 

Other than the “got grant” specification, all variables are as defined above. 

Including the “got grant” variable provides a test for whether the effects of 

COPS grants occurred in the year in which the money was actually 

spent—as we specified in equations (1) and (2)—or whether the 

announcement of a grant award led to changes in officers and, 

subsequently, crime. If the announcement of the award were more 

important than the actual expenditures, it would imply that estimates of 

the effect of changes in expenditures on officers or crime in equations (1) 

and (2) would overstate the effects. To address this, we added indicator 

variables for the year in which a grant was received. Additionally, the 
Appendix VI: Methods Used to Estimate the 

Effects of COPS Funds on Officers and Crime 

Page 80 GAO-06-104 Community Policing Grants 

quadratic term for COPS hiring grant expenditures provides a test for 

nonlinear effects of COPS hiring grants on crime. This specification 

examines whether the effects of officers on crime diminish as the number 

of officers rises above certain levels. 

We use data on 4,247 police agencies that reported complete crime (12 

months of crime) in any year and that served populations of 10,000 or 

more persons. These agencies represented about 23 percent of the 

agencies that appeared in the UCR data that we received from the FBI. 

However, they also covered more than 86 percent of the crimes and they 

represented about 77 percent of the population in the UCR data that we 

received. Because of concerns about data quality, we restricted our sample 

to agencies that met these criteria of complete crime reporters and serving 

populations larger than 10,000 persons. Across years, the number of 

agencies that met these conditions varies, so our panel of data is 

unbalanced. We used grant expenditure data from the OJP financial data, 

which we linked to the crime and officer records of agencies. We included 

county level demographic and economic data from the Census Bureau, the 

National Center for Health Statistics, and the Bureau of Economic 

Analysis. (See app. I for more information regarding the construction of 

the dataset.) 

Table 15 provides the means and standard deviations of the variables 

included in the regression models. As shown in the table, the per capita 

expenditures derived from COPS hiring grants exceeded the per capita 

amounts from other federal grants. 

Data Used in Our 

Analysis 
Appendix VI: Methods Used to Estimate the 

Effects of COPS Funds on Officers and Crime 

Page 81 GAO-06-104 Community Policing Grants 

Table 15: Means and Standard Deviations of Variables Used in Regression Models 

Variables Mean

Standard 

deviation

Officers per 10,000 persons 20.31 12.37

Federal grant expenditures per capita 

 COPS hiring 0.978 2.18

 COPS MORE 0.292 1.35

 COPS innovative 0.082 0.496

 COPS miscellaneous 0.003 0.043

 Byrne discretionary 0.045 0.471

 LLEBG 0.770 1.93

Crime rate variables (per 100,000 persons) 

 Total index crime 5,349 3,170

 Murder 8.7 10.9

 Forcible rape 38 31

 Robbery 247 317

 Aggravated assault 424 391

 Burglary 1,034 647

 Larceny theft 2,990 1,752

 Motor vehicle theft 608 593

Other control variables 

 Log per capita income 10.12 0.33

 Employment-to-population ratio 0.631 0.453

 Fraction of population aged 15 through 24 0.141 0.027

 Fraction of population nonwhite 0.186 0.136

Source: GAO analysis of Uniform Crime Report, Office of Justice Programs financial, Bureau of Economic Analysis, National Center for 

Health Statistics, and U.S. Census Bureau data. 

In this section, we discuss our regression analyses and describe how we 

arrived at the results that are discussed in this report. 

To arrive at the effects of COPS expenditures on officers, we estimated 

specifications for equation (1), as shown in table 16. With only the fixed 

effects, the models explain more than 90 percent of the variation in officer 

strength. In specification 1, we added only the COPS hiring grant 

Explanation of the 

Results of Our 

Analysis 

The Effect of COPS 

Expenditures on the 

Number of Police Officers 
Appendix VI: Methods Used to Estimate the 

Effects of COPS Funds on Officers and Crime 

Page 82 GAO-06-104 Community Policing Grants 

expenditures per capita to the model that contained only the fixed effects. 

The effects of hiring grants are significant at the 1 percent level, and the 

coefficient indicates that an additional dollar of hiring grant expenditures 

per capita changes the officer rate (measured per 10,000 persons) by 0.317. 

In specifications 2 through 5, we introduce various combinations of the 

growth rate cells, demographic and economic conditions, and the other 

grant types. Across specifications 2 through 5, the estimated coefficient on 

the hiring grant variable remains fairly consistent, ranging from 0.227 in 

specification 5 to 0.261 in specification 3, where the interpretation of the 

coefficient is the effect of a $1 increase in per capita COPS hiring grant on 

the per 10,000 person rate of officers. Specification 5 presents our 

preferred specification, in that it includes all of the relevant controls. 

Using the coefficient on COPS hiring grant expenditures from 

specification 5, we calculate the effect of $25,000 in COPS hiring grant 

expenditures in a given year to produce roughly 0.6 additional officers in a 

given year.14 Finally, in addition to the COPS hiring grant expenditures, 

COPS MORE and LLEBG grant expenditures also consistently predict 

officer strength, as indicated by the MORE and LLEBG parameter 

estimates in specifications 2 through 5. 

 14Bearing in mind that the officer strength is per 10,000 in the population, we arrive at this 

result by the following calculation: (25,000)*(.227/10,000) = 0.57 officers. 
Appendix VI: Methods Used to Estimate the 

Effects of COPS Funds on Officers and Crime 

Page 83 GAO-06-104 Community Policing Grants 

Table 16: Parameter Estimates from Regressions of Officers Per Capita on COPS 

Hiring Grant Expenditures and Other Outside Funds (Standard Errors in 

Parentheses) 

Variable 1 2 3 4 5 

Hiring 0.317 

(0.055)

0.231 

(0.025) 

0.261 

(0.047) 

0.247 

(0.028)

0.227 

(0.025)

MORE 0.124 

(0.043) 

0.238 

(0.090) 

0.159 

(0.054)

0.121 

(0.043)

Innovative 0.0477 

(0.050) 

–0.029 

(0.075) 

0.042 

(0.054)

0.047 

(0.050)

Miscellaneous 1.46 

(1.20) 

0.906 

(1.30) 

1.13 

(1.28)

1.43 

(1.19)

Byrne 0.001 

(0.06) 

0.169 

(0.129) 

0.148 

(0.102)

0.0003 

(0.06)

LLEBG 0.172 

(0.05) 

0.259 

(0.065) 

0.201 

(0.049)

0.168 

(0.049)

Federal non-COPS 0.056 

(0.045) 

0.022 

(0.066) 

0.033 

(0.047)

0.053 

(0.045)

Demographic and economic 

covariatesa

No No Yes Yes Yes

Population weights Yes Yes Yes Yes Yes

Growth rate cells No Yes No Yes Yes

State-by-year fixed effects No Yes No No Yes

Source: GAO analysis of Uniform Crime Report, Office of Justice Programs financial, Bureau of Economic Analysis, National Center for 

Health Statistics, and U.S. Census Bureau data. 

Notes: Officers per capita is measured in terms of officers per 10,000 persons; all expenditure 

variables are in per capita amounts. All regression specifications include agency and year fixed 

effects. Bold-face parameter estimates and standard errors indicate that a parameter estimate is 

statistically significant at the 5 percent level using robust standard errors. 

a

Demographic and economic covariates include log per capita income, employment to population 

ratio, percentage of population between 15 and 24 years of age, and percentage of population that is 

nonwhite. 

Our reduced-form estimates of the effects of COPS expenditures on crime, 

the result of our estimating equation (2) appear in table 17. This first 

column (labeled “Officers”) repeats the results from specification 5 of 

table 16. The other columns of table 17 show the parameter estimates for 

the effects of hiring grants and outside funds on the crime rate for index 

crimes and separately for type of index crime (except for arson). With the 

exception of rape, COPS hiring grant expenditures per capita have a 

negative effect on index crime rates and the crime rate for each type of 

index crime. Further, while the direction of the effect of the hiring grant 

variable on the larceny rate is negative, the effect is not significant at the 5 

Effect of COPS 

Expenditures on Crime 
Appendix VI: Methods Used to Estimate the 

Effects of COPS Funds on Officers and Crime 

Page 84 GAO-06-104 Community Policing Grants 

percent level. LLEBG expenditures have a negative and significant effect 

on all crime types. The other grant fund types have a negative effect on 

some crime types. 

We estimated the effect of COPS hiring grant expenditures on index 

crimes to be -29.19. In other words, $1 in COPS hiring grant expenditures 

per capita translates into a reduction of almost 30 index crimes per 

100,000 people. 

Table 17: Parameter Estimates from Regressions of Crime Rates on COPS Hiring Grant Expenditures and Other Outside 

Funds (Standard Errors in Parentheses) 

 Officers Index Murder Rape Robbery Assault Burglary Larceny

Motor 

vehicle

1 2 3 4 5 6 7 8 9

Variable 

Hiring 0.227 

 (0.025) 

–29.19 

(6.67) 

–0.133

 (0.028)

0.128

 (0.075)

–4.94 

(1.07)

–2.77

 (1.08)

–8.01 

(1.33) 

–4.18 

(3.05)

–9.26 

(3.44)

MORE 0.121 

 (0.043) 

–17.14 

 (6.55) 

–0.083 

(0.031)

0.008

 (0.063)

–2.80

(0.919)

–1.72

 (0.86)

–2.04 

(1.14)

–6.91 

(3.43)

–3.58

 (1.51)

Innovative 0.047 

 (0.050) 

–88.25 

(17.80) 

–0.219

(.081)

–0.102

(.255)

–8.45

(2.13)

–9.71

(3.80)

–17.62 

(4.81) 

–23.30

(11.5)

–28.8

(6.77)

Miscellaneous 1.43 

(1.19) 

–123.7 

(18.79)

1.13

(.887)

2.37

(2.31)

41.2

(29.74)

–13.56

(33.27)

–90.61 

(36.15)

–121.8

(101.4)

57.51

(46.98)

Byrne 0.0003 

(0.06) 

11.72 

(16.03) 

-.099

(.069)

–0.388

(.280)

.270

(1.61)

7.01

(1.33)

–0.172 

(3.87) 

10.16

(10.14)

–5.25

(3.39)

LLEBG 0.168 

(0.049) 

–73.13 

(10.60) 

–0.365

(.051)

–0.784

(.132)

–13.07

(1.68)

–16.00

(2.09)

–16.06 

(2.31) 

–15.2

(3.87)

–11.59

(2.20)

Federal nonCOPS 0.053 

(0.045) 

22.96 

(9.14)

.027

(.038)

.082

(.090)

2.25

(1.07)

1.57

(1.34)

1.34 

(1.60) 

10.40

(5.07)

7.28 

(1.90)

Source: GAO analysis of Uniform Crime Report, Office of Justice Programs financial, Bureau of Economic Analysis, National Center for 

Health Statistics, and U.S. Census Bureau data. 

Notes: All regressions include agency and year fixed effects, state-by-year fixed effects, and growth 

rate cells. Additionally, regressions include log per capita income, employment over population ratio; 

percentage of county population aged 15 to 24; and percentage nonwhite. Officers are per 10,000 

persons; all grant expenditures are per capita amounts. Observations are weighted by the population 

of the agency to obtain the national effect. Bold-face parameter estimates and standard errors 

indicate that a parameter estimate is statistically significant at the 5 percent level using robust 

standard errors. 
Appendix VI: Methods Used to Estimate the 

Effects of COPS Funds on Officers and Crime 

Page 85 GAO-06-104 Community Policing Grants 

Given the variation in per capita COPS expenditures that occurred across 

agencies serving populations of different sizes, we explored whether 

COPS hiring grants had different effects on crime rates based on the size 

of the population served by agencies. We stratified agencies into four 

population size groups: those serving populations of between 10,000 and 

25,000 persons; between 25,000 and 50,000 persons; between 50,000 and 

150,000 persons; and more than 150,000 persons. We found that the effect 

of the hiring grant was consistent across all population categories less 

than 150,000, but insignificant in the population category of more than 

150,000 persons. We found that negative effect of COPS hiring grants on 

index crime rates ran across all population size categories. However, the 

effects of hiring grants were largest in the 50,000 to 150,000 population 

category, and insignificant in the 25,000 to 50,000 population category 

(table 18). 

Table 18: Parameter Estimates from Regressions of Index Crime Rates and Officers Per Capita on COPS Hiring Grant 

Expenditures and Other Outside Funds, by Population Size Category (Standard Errors in Parentheses) 

 Population 

10,000 to fewer than 

25,000 

25,000 to fewer 

than 50,000 

50,000 to fewer than 

150,000 More than 150,000 

Officers Index Officers Index Officers Index Officers Index

1 2 3 4 5 6 7 8

Grant 

Hiring .180 

(.019) 

-10.11 

(4.74) 

.288

(.032)

-8.79

(10.00)

.245

(.034)

-39.1 

(10.1) 

.095

(.074)

-31.5

(15.2)

MORE .043 

(.021)

2.86 

(2.32) 

.027

(.027)

-14.67

(13.25)

.102

(.069)

3.79 

(14.16) 

.053

(.148)

-35.2

(24.0)

Innovative -.007 

(.043) 

-19.94 

(20.67) 

-.058

(.137)

-28.8

(36.9)

.036

(.052)

-87.7 

(23.3) 

-.043

(.130)

-108

(48.32)

Miscellaneous -.282 

(.360) 

-379 

(179)

-.338

(.692)

-473

(234)

-.996

(.574)

-145 

(231) 

4.79

(1.97)

-161

(368)

Byrne -.010 

(.074) 

-7.87 

(12.74) 

.440

(.516)

-4.37

(55.52)

-.084

(.084)

24.88 

(29.91) 

.173

(.153)

40.2

(26.5)

LLEBG .010 

(.013) 

-23.08 

(6.87)

.032

(.046)

-141.3

(18.28)

-.012

(.069)

-109 

(15.6)

.492

(.176)

-90.4

(22.6)

Federal nonCOPS .031 

(.016) 

-1.177 

(4.74) 

-.087

(.113)

20.06

(16.79)

-.016

(.096)

36.06 

(13.03)

.045

(.127)

11.4

(32.6)

Source: GAO analysis of Uniform Crime Report, Office of Justice Programs financial, Bureau of Economic Analysis, National Center for 

Health Statistics, and U.S. Census Bureau data. 

The Effects of Different 

Population Sizes across 

Agencies 
Appendix VI: Methods Used to Estimate the 

Effects of COPS Funds on Officers and Crime 

Page 86 GAO-06-104 Community Policing Grants 

Notes: All regressions include agency and year fixed effects, state-by-year fixed effects, and growth 

rate cells. Additionally, regressions include log per capita income, employment over population ratio; 

percentage of county population aged 15 to 24; and percentage nonwhite. Officers are per 10,000 

persons; all grant expenditures are per capita amounts. Observations are weighted by the population 

of the agency to obtain the national effect. Bold-face parameter estimates and standard errors 

indicate that a parameter estimate is statistically significant at the 5 percent level using robust 

standard errors. 

As COPS hiring grants were to be used only to hire officers, we explored 

their use as an instrument to predict the effect of officers on crime. 

Assuming that COPS grants were used in that way, our preferred 

specification from our regressions crime on COPS hiring grants and other 

outside funds would produce estimates of the elasticity of crime with 

respect to officers that are shown in table 19. 

To assess the degree to which the elasticities that we calculated were in 

line with those appearing in the economics of crime literature, we 

compared our elasticities with those estimated by Evans and Owens 

(2004), Levitt (1997), Levitt (2002), and Klick and Tabarrok (2005). Our 

estimates are in line with those in the literature (table 19). 

Table 19: Elasticities of the Impact of Police Officers on the Crime Rate 

Elasticity Murder Rape Robbery Assault Burglary Larceny

Motor 

vehicle

1 2 3 4 5 6 7

Estimate 

Average crime rate 1993 11 40 311 484 1183 3173 703

Levitt 1997a –1.98 –0.27 –0.79 –1.09 –0.05 –0.43 –0.50

Levitt 2002 –0.91 –0.03 –0.45 0.40 –0.20 –0.14 –1.70

Evans and Owens 2005b –0.84 –0.42 –1.34 –0.96 –0.59 –0.08 –0.85

GAO (this report) –1.04 0.28 –-1.36 –0.49 –0.58 –0.11 –1.12

Klick and Tabarrok 2005 –0.30

GAO aggregate elasticity, by crime category 

Index –0.42 

Violent –0.78 

Property –0.36 

Source: GAO analysis of Uniform Crime Report, Office of Justice Programs financial, Bureau of Economic Analysis, National Center for 

Health Statistics, and U.S. Census Bureau data. 

Notes: Estimates are derived from the parameter estimates in tables 16 and 17. The average police 

count per 10,000 in 1993 is 19.38. Crime is per 100,000. 

a

Levitt’s (1997) elasticities are taken directly from his regression specification. Levitt calculates 

elasticities for a range of alternate specifications that are not reported here. 

Calculations of the 

Elasticity of Crime with 

Respect to Officers 
Appendix VI: Methods Used to Estimate the 

Effects of COPS Funds on Officers and Crime 

Page 87 GAO-06-104 Community Policing Grants 

b

Evans and Owens’ (2005) elasticities were evaluated at the same mean level of crime as were 

GAO’s. 

In addition, Evans and Owens report aggregate point elasticities for violent 

and property crimes of –0.99 and –0.26, respectively, and Levitt reports 

aggregate point elasticities for violent and property crimes of –0.44 and 

–0.50, respectively. Our aggregate elasticities for violent and property 

crimes fall between these two sets of estimated point elasticities. 

Equations (1) and (2) depend on certain assumptions about the way that 

COPS hiring grant expenditures and other outside funds affect officers and 

crime. For example, the specifications reported previously only allow the 

effect of the federal funds to affect crime contemporaneously. However, it 

may take a certain amount of time for the expenditures to have an effect 

on either officers or crime, as it may take a certain amount of time for new 

officers to become fully acclimated to a department, or to become 

proficient in their duties. To explore the robustness of our findings under 

varying assumptions about how COPS hiring grant expenditures could 

affect officers and crime, we recalculated our elasticities after estimating 

our regressions under the specifications outlined previously in table 20. 

We report the elasticities that we calculated from these various regression 

models (in the last three rows of the table). The elasticities for index 

crimes range from –0.41 to –0.95; those for violent crimes range from –0.76 

to –1.8; and those for property crimes range from –0.35 to –0.8. The 

elasticities that we report in our results all fall at the lower end of the 

range of elasticities that we estimated. 
Appendix VI: Methods Used to Estimate the 

Effects of COPS Funds on Officers and Crime 

Page 88 GAO-06-104 Community Policing Grants 

Table 20: Elasticity of Violent and Property Crime with Respect to Officers under 

Alternate Specifications of the Relationship between COPS Expenditures and Crime 

Variables in specification 1 2 3 4 5

MORE, Innovative, and Miscellaneous COPS 

expenditures 

x x x

LLEBG, Byrne discretionary, and other federal nonCOPS expenditures x x x

“Got grant” specification x

Lagged values of MORE, Innovative, and 

Miscellaneous COPS expenditures 

 x x

Lagged values of LLEBG, Byrne discretionary, and 

other federal non-COPS expenditures 

 x x

Demographic and economic controls x x x x x

Growth rate cells x x x x

Lagged value of Hiring grant expenditures x

Quadratic term for Hiring grant expenditures x 

State by year fixed effects x x x x

Elasticity 

Violent crimes –1.17 –.76 –1.8 –.81 –.76 

Property crimes –.51 –.35 –.80 –.37 –.35 

Index crimes –.61 –.41 –.95 –.44 –.41 

Source: GAO analysis of Uniform Crime Report, Office of Justice Programs financial, Bureau of Economic Analysis, National Center for 

Health Statistics, and U.S. Census Bureau data. 

Note: An X indicates that a variable was included in a specification. 

We used our regression results to derive estimates of the net number of 

officers paid for by COPS grant expenditures separately for each year. By 

net number of officers, we refer to the increase in the number of officers 

on the street attributable to COPS net of attrition. For example, if at the 

beginning of a year, there were 100 officers on the street, while during a 

year COPS grants were responsible for hiring 10 officers and 5 officers left 

the force, the net number of officers due to COPS would be 5. 

To obtain the total number of officer-years due to COPS expenditures, we 

summed the number of officers across years. Table 21 presents the 

estimated number of officers that COPS expenditures funds paid for in 

each year. In column 1 we present the actual number of per capita officers 

used in our regressions that generated the results in table 21. Not shown in 

the table, but used in the calculation of the number of officers due to 

COPS expenditures are the per capita amounts of COPS expenditures, 

Estimating the Net 

Number of Officers Paid 

for by COPS Expenditures 
Appendix VI: Methods Used to Estimate the 

Effects of COPS Funds on Officers and Crime 

Page 89 GAO-06-104 Community Policing Grants 

including COPS hiring, MORE, innovative, and miscellaneous grant 

expenditures. Column 2 presents our estimate of what the per capita 

number of officers would have been absent the COPS expenditures. 

Columns 3 and 4 show the number of officers per capita and the 

percentage of officers per capita explained by COPS expenditures. 

Column 5 presents our estimates of the number of officers in each year in 

the sample of agencies that we analyzed that were explained by COPS 

expenditures. To arrive at the number of officers in the United States due 

to COPS expenditures, we weighted the numbers in column 5 up to the 

U.S. population total (in column 6). On the basis of this analysis, in year 

2000, for example, when they peaked, the COPS expenditures per capita 

were responsible for about 2.9 percent of the net increase in officers in the 

United States, or more than 17,000 officers. Across all years, we estimate 

that COPS was responsible for an increase of about 88,000 officer-years 

during the years from 1994 through 2001. 

Table 21: Estimated Per Capita Effect of COPS Expenditures on the Number of Officers 

Police per 

10,000 population 

Police explained by 

COPS funds Number of police in 

Number Minus COPS funds Per capita

Percentage 

difference Sample United States

Year 1 2 3 4 5 6

1991 19.32 19.32 0 0 0 0

1992 19.32 19.32 0 0 0 0

1993 19.38 19.38 0 0 0 0

1994 19.65 19.65 0.003 0.02 64 84

1995 20.55 20.47 0.07 0.35 1,407 1,916

1996 20.71 20.39 0.32 1.55 6,210 8,639

1997 21.05 20.54 0.51 2.42 10,085 13,897

1998 21.18 20.54 0.64 3.02 12,900 17,630

1999 21.61 21.02 0.59 2.72 12,153 16,415

2000 21.15 20.53 0.62 2.91 13,335 17,387

2001 20.89 20.46 0.43 2.05 9.535 12,226

Total 65,688 88,195

Source: GAO analysis of Uniform Crime Report, Office of Justice Programs financial, Bureau of Economic Analysis, National Center for 

Health Statistics, and U.S. Census Bureau data. 
Appendix VI: Methods Used to Estimate the 

Effects of COPS Funds on Officers and Crime 

Page 90 GAO-06-104 Community Policing Grants 

On the basis of our analysis of the increase in officers attributable to COPS 

expenditures, we estimated the amount of crime that could be attributable 

to COPS, given the estimated effect of COPS expenditures on officers. On 

the basis of our analysis of the number of officers due to COPS 

expenditures and our estimated elasticities of crime with respect to 

officers, we can estimate the number of crimes associated with COPS 

expenditures through the increase in officers attributable to these 

expenditures. In table 22, we show our calculations of the decline in crime 

attributable to COPS for each year, compared with the 1993 levels of 

crime, the pre-COPS baseline year. 

Columns 1 through 3 of table 22 give the average crime rates per 100,000 

persons in the agencies in our sample. Columns 4 through 6 give the 

percentage change from 1993 in crime rates for each category of crime. 

Columns 7 though 9 report data on officers. Column 7 reports the growth 

in the officer rate from 1993 due to the change in COPS expenditures. 

Column 8 presents the growth (from column 7) as a percentage change 

from 1993. Columns 9 through 11 provide estimates of the percentage 

change in crime rates from 1993 using the elasticities shown in table 22. 

Finally, columns 12 through 14 provide the estimated amount of change in 

crime rates from 1993 that arise from COPS expenditures. 

Estimating the Number of 

Crimes Reduced by COPS 

Expenditures 
Appendix VI: Methods Used to Estimate the 

Effects of COPS Funds on Officers and Crime 

Page 91 GAO-06-104 Community Policing Grants 
Appendix VI: Methods Used to Estimate the 

Effects of COPS Funds on Officers and Crime 

Page 92 GAO-06-104 Community Policing Grants 

Table 22: Estimated Per Capita Growth of COPS Expenditures on Police Officers 

and Crime from 1993 

Average number 

of crimesa 

Percentage change 

in crimeb

Violent Property Total Violent Property Total

Year 1 2 3 4 5 6

1991 868 5519 6,387 

1992 854 5235 6090 

1993 846 5058 5904 

1994 816 4973 5789 -3.55 -1.68 -1.95

1995 784 4919 5703 -7.33 -2.75 -3.42

1996 723 4718 5440 -14.54 -6.72 -7.86

1997 697 4593 5290 -17.61 -9.19 -10.40

1998 649 4313 4962 -23.29 -14.73 -15.96

1999 588 3947 4535 -30.50 -21.97 -23.19

2000 568 3799 4367 -32.86 -24.91 -26.03

2001 561 3845 4406 -33.69 -23.98 -25.37
Appendix VI: Methods Used to Estimate the 

Effects of COPS Funds on Officers and Crime 

Page 93 GAO-06-104 Community Policing Grants 

Number of officersc

Expected percentage change 

in crime due to COPS funds 

Change in crime per 

100,000 persons 

Predictedd

Percentage 

change Violent Property Total Violent Property Total

7 8 9 10 11 12 13 14

 

19.38 

19.38 .02 -.01 -.01 -.01 -.09 -.25 -.34

19.45 .37 -.29 -.13 -.16 -2.08 -5.90 -8.01

19.70 1.65 -1.29 -.60 -.70 -9.56 -27.11 -36.75

19.89 2.63 -2.05 -.95 -1.11 -15.48 -43.86 -59.47

20.02 3.30 -2.57 -1.19 -1.39 -19.67 -55.74 -75.58

19.97 3.04 -2.36 -1.10 -1.28 -19.26 -54.57 -74.00

20.00 3.18 -2.48 -1.15 -1.34 -20.19 -57.22 -77.59

19.81 2.21 -1.72 -.80 -.93 -14.08 -39.90 -54.10

Source: GAO analysis of Uniform Crime Report, Office of Justice Programs financial, Bureau of Economic Analysis, National Center for 

Health Statistics, and U.S. Census Bureau data. 

a

Average number of crimes per 100,000 for the agency; means are weighted by population. 

b

Percentage change in crime from 1993. 

c

Column 7 is the predicted level in the number of officers from only a change in COPS funds from 

1993; column 8 is the percentage change from 1993. 

d

Predicted number of officers due to growth in COPS funds, from base 1993 level of officers of 19.38 

per 10,000 persons. 
Appendix VII: Methods Used to Assess 

Policing Practices 

Page 94 GAO-06-104 Community Policing Grants 

Our objective in assessing policing practices was to determine the extent 

to which COPS grant expenditures were associated with police 

departments’ adoption of policing activities or practices that may have 

contributed to reduction in crime during the 1990s. To determine whether 

COPS grants were associated with changes in policing practices, we 

analyzed data from two national surveys of local law enforcement 

agencies on the policing practices that they reportedly implemented in 

various years from 1993 to 2000. In addition, we analyzed systematic 

reviews of research on the effectiveness of policing practices in preventing 

crime. 

To address whether COPS grants were associated with changes in policing 

practices that may be associated with preventing crime, we analyzed data 

from the two administrations of the Policing Strategies Survey (in 1993 

and 1997) and two of the four administrations of the National Evaluation 

of COPS Program Survey (in 1996 and 2000). Because the purposes of the 

surveys differed, each used different samples of agencies (with some 

agencies appearing in both surveys). The Policing Strategies Survey drew a 

sample representative of all municipal police, county police, and county 

sheriff agencies in the United States with patrol functions and with more 

than five sworn officers in 1992, and the National Evaluation of COPS 

Program Survey drew a sample that was representative of all law 

enforcement agencies believed to be in existence in the United States that 

had received, or were eligible to receive a COPS grant. Each survey 

provided respondents in police agencies with lists of items that identified 

specific types of policing practices, and respondents were asked whether 

they had implemented each of the practices on the list. Survey responses 

were obtained from knowledgeable officials within each agency, such as 

the police chief or the chief’s designee. The number of items related to 

policing practices differed between the two surveys. 

We classified items in the surveys into four categories of policing practices 

corresponding to general approaches to policing identified in the criminal 

justice literature: problem-solving practices, place-oriented practices, 

community collaboration activities, and crime analysis activities. Problemsolving practices call for police to focus on specific problems and tailor 

their strategies to the identified problems. Place-oriented practices include 

attempts to identify the locations where crime occurs repeatedly and to 

implement procedures to disrupt these recurrences of crime. Community 

collaboration practices include improving citizen feedback about crime 

problems and the effectiveness of policing efforts to address these 

problems. Crime analysis includes the use of tools such as geographic 

Appendix VII: Methods Used to Assess 

Policing Practices 

Methods to Address 

Changes in Policing 

Practices 
Appendix VII: Methods Used to Assess 

Policing Practices 

Page 95 GAO-06-104 Community Policing Grants 

information systems to identify crime patterns. These tools may help an 

agency support other practices for preventing crime, such as problemsolving and place-oriented practices. 

Three social science analysts with research experience in criminal justice 

independently reviewed the list of policing practice items in each survey 

and placed each item in one of the four categories or determined that the 

item did not fit in any of the four categories. Following initial 

classification, the analysts met to discuss and address any inconsistencies 

in their classification of items. 

After classifying practices, we created an index to represent the total 

number of problem-solving, place-oriented, community collaboration, and 

crime analysis practices, and we gave each agency that responded to both 

waves of a survey a score equal to the number of these practices that the 

agency reportedly implemented in the survey years. We also identified, for 

each agency, the number of practices in each of the four categories. 

We then analyzed the levels and changes in reported practices within each 

survey. Our analysis focused on the differences in levels of practices 

reported by agencies that received COPS grants and those that did not 

receive them. To assess the influence of COPS grant expenditures on 

reported practices, we analyzed changes in reported practices as a 

function of the per capita amounts of COPS dollars spent by agencies. For 

agencies that did not receive COPS grants, we set their per capita COPS 

expenditure amounts to zero. 

A limitation of our analysis is that the surveys did not ask explicitly about 

the extent to which each listed practice was implemented by law 

enforcement agencies. Thus agencies that report that they had 

implemented a specific practice may vary considerably, from sporadic use 

of the practice among a subset of officers in the agency to more frequent 

use of the practice throughout the agency. 
Appendix VII: Methods Used to Assess 

Policing Practices 

Page 96 GAO-06-104 Community Policing Grants 

The Policing Strategies Survey was administered in 1993 and again in 1997. 

The Police Foundation administered the 1993 wave of the survey, and ORC 

Macro International, Inc. and the Police Executive Research Forum 

administered the 1997 wave of the survey.1

 The sampling frame for both 

the 1993 and 1997 waves consisted of 11,824 local police and sheriffs’ 

departments listed in the Law Enforcement Sector portion of the 1992 

Justice Agency list developed by the U.S. Bureau of the Census. In 

constructing the sampling frame, state police departments, special police 

agencies, agencies that did not perform patrol functions, and agencies 

with fewer than five sworn personnel were excluded from the larger list of 

all law enforcement agencies. A total of 2,337 police and sheriffs’ 

departments were selected to be in the main sample for the 1993 survey, 

and surveys were mailed to 2,314 of them after 23 agencies were found to 

be out of scope before the surveys were mailed.2

 Follow-up mailings and 

facsimile reminders were sent to nonrespondents. The overall response 

rate for the 1993 survey was 71.3 percent. All of the agencies in the first 

sample were then selected for participation in the 1997 survey. The survey 

employed a multiphased data collection approach, using postal mail for 

the first phase, followed by facsimile reminders, a second mailing, and 

computer-assisted telephone interviewing for nonrespondents. The 

response rate for the 1997 survey was 74.7 percent. A total of 1,269 

agencies were present in both the 1993 and 1997 surveys. The sample was 

a stratified random sample with probability of inclusion varying by the 

number of sworn personnel (5-9; 10-49; 50-99; and 100 or more sworn 

personnel).3

 1

The 1993 survey was designed to provide information on what was occurring and what 

needed to occur in the development and implementation of community policing. The 1997 

survey was designed to provide information on the most current practices and trends in 

community policing. See: A. Rosenthal et al, Community Policing: 1997 National Survey 

Update of Police and Sheriffs’ Departments, ORC Macro and Police Executive Research 

Forum, Washington D.C.: National Institute of Justice, April 2001. 

2

Agencies were considered out of scope if they had fewer than five sworn officers, no 

patrol function, or were a state police agency or other “special” police agency. 

3

When ORC Macro and the Police Executive Research Foundation drew the sample for the 

1997 wave of the survey, they discovered that instead of excluding agencies with fewer 

than five sworn officers, the Police Foundation had used information on the agencies’ total 

number of employees to select the agencies for the sampling frame and had excluded 

agencies with fewer than five employees. Thus some agencies were misclassified, and 

some were included that should not have been. In addition, the weights provided with the 

1993 data were incorrect for agencies with 10 to 49 employees. ORC Macro and PERF were 

able to assign the appropriate weights retroactively to the 1993 sample and were able to 

exclude agencies with fewer than five sworn officers. 

Characteristics and 

Analysis of the Policing 

Strategies Survey 
Appendix VII: Methods Used to Assess 

Policing Practices 

Page 97 GAO-06-104 Community Policing Grants 

We identified agencies in the Policing Strategies Survey that responded to 

both waves of the survey and had complete data on each of the policing 

practices items, and of these, we were able to link the data from 1,188 

agencies to our larger database on crime, officers, money, and economic 

conditions.4

 For comparability with the analyses of the effects of funding 

on officers and crime, we limited our analysis to those agencies serving 

jurisdictions with populations of 10,000 or more persons. This resulted in 

usable data on 1,003 agencies. 

We used the Policing Strategies Survey data to compare reported changes 

in the types and levels of policing practices that occurred during the COPS 

program with pre-COPS levels of practices. The analyses reported in this 

appendix are weighted to adjust for the sample design effects. The findings 

are generalizable to all municipal police agencies, county police agencies, 

and county sheriff agencies in the United States with patrol functions and 

serving jurisdictions with populations of 10,000 or more persons. 

We used 38 items on policing practices from the Policing Strategies 

Survey. We combined 12 practices pertaining to increasing officer contact 

with citizens and improving citizen feedback into a community 

collaboration index. We used 6 items on the crime analysis units within 

police departments to create our index of crime analysis. We combined 8 

practices pertaining to increasing enforcement activity or place 

management in buildings, neighborhoods, or other specific places into an 

index of place-oriented practices. And we compiled the data on 12 items 

that reflected organizational efforts to reduce or interrupt recurring 

mechanisms that may encourage crime into a problem-solving practices 

index. The classification of items from the Policing Strategies Survey into 

our four indexes of types of policing practices is shown in table 23. 

 4

These agencies represented about 94 percent of the agencies that responded to both 

waves of the Policing Strategies Survey. 
Appendix VII: Methods Used to Assess 

Policing Practices 

Page 98 GAO-06-104 Community Policing Grants 

Table 23: Categories of Policing Practices and Specific Items within Each Category 

in the Policing Strategies Survey 

Community collaboration 

Agency uses foot patrol as a specific assignment 

Agency uses foot patrol as a periodic expectation for officers assigned to cars 

Agency uses citizen surveys to determine community needs and priorities 

Agency uses citizen surveys to evaluate police service 

Patrol officers conduct surveys in area of assignment 

Patrol officers meet regularly with community groups 

Supervisors maintain regular contact with community leaders 

Agency has permanent, neighborhood-based offices or stations 

Agency has mobile, neighborhood-based offices or stations 

Patrol officers make door-to-door contacts in neighborhoods 

Patrol officers develop familiarity with community leaders in area of assignment 

Patrol officers assist in organizing community 

Crime analysis 

Agency has a decentralized crime analysis unit/function 

Agency has a centralized crime analysis unit/function 

Supervisors manage crime analysis for geographic area of responsibility 

Geographically based crime analysis made available to officers at the beat level 

Patrol officers conduct crime analysis for area of assignment 

Agency has means of accessing other city or county databases to analyze 

community or neighborhood conditions 

Place-oriented practices 

Agency designates some officers as “community” or “neighborhood” officers 

Agency uses building code enforcement as a means of helping remove crime 

Agency has landlord/manager training programs for order maintenance and drug 

reduction 

Command or decision-making responsibility tied to neighborhoods or beats 

Patrol officers enforce civil and code violations in area 

Fixed assignment of patrol officers to specific beats or areas 

Agency uses other regulatory codes to combat drugs and crime 

Agency has beat or patrol boundaries that coincide with neighborhood boundaries 

Problem-solving practices 

Agency prepares agreements specifying work to be done on problems by citizens 

and police 

Specific training provided to officers for problem identification and resolution 

Training for citizens in problem identification or resolution 
Appendix VII: Methods Used to Assess 

Policing Practices 

Page 99 GAO-06-104 Community Policing Grants 

Patrol officers teach residents how to address community problems 

Interagency involvement in problem identification and resolution 

Line supervisors elicit input from officers/deputies about solutions to community 

problems 

Multidisciplinary teams to deal with special problems such as child abuse and 

neglect 

Specialized problem-solving unit 

Patrol officers work with citizens to identify and resolve area problems 

Citizens work with police to identify and resolve community or neighborhood 

problems 

Organization has been redesigned to support problem solving efforts 

Patrol officers work with other city agencies to solve neighborhood problems 

Source: Policing Strategies Survey, 1993 and 1997. 

Note: Each individual item is coded dichotomously (yes/no) to indicate whether an agency 

implemented the specific practice. 

The Policing Strategies Survey provided us with an opportunity to assess 

changes in reported policing practices using a pre-COPS grant and withinCOPS grant program framework. The 1993 administration of this survey 

occurred several months prior to the distribution of the first COPS grants, 

while the 1997 administration occurred after COPS grants had been made 

to about 75 percent of the agencies in the sample. To implement the prewithin examination of the effects of COPS grants on policing practices, we 

first compared the levels of practices in 1993 and 1997 between the group 

of agencies that had received a COPS grant by 1997 and the group that had 

not received a COPS grant by 1997. 

Second, we estimated separate regressions of the effect of the receipt of a 

COPS grant and of the cumulative per capita amount of COPS 

expenditures on the levels of reported policing practices. To assess the 

extent to which COPS grant expenditures were associated with changes in 

reported policing practices, we estimated regressions of the changes in 

reported policing practices that occurred within agencies as a function of 

the cumulative per capita amount of COPS grant expenditures that they 

made during the years from 1994 through 1997. We used two-factor fixedeffects regression techniques, which allowed us to control for unobserved 

characteristics of agencies and underlying trends in the adoption of 

policing practices. We also controlled for economic conditions and 

population changes in the localities in which the agencies were located. In 

addition, we used weighted regressions to address nonresponse patterns 

and the probability with which the original sampling units were drawn. 
Appendix VII: Methods Used to Assess 

Policing Practices 

Page 100 GAO-06-104 Community Policing Grants 

Our regression equations show that both the receipt of a COPS grant and 

the amount of per capita COPS expenditures by agencies were associated 

with increases in the levels of reported policing practices between 1993 

and 1997. Agencies that received at least one COPS grant had significantly 

larger changes in the overall number of practices than did agencies that 

did not receive a COPS grant during this period. Specifically, of the 

roughly 2.9 average increase in the number of practices reported by 

agencies over this period, the receipt of a COPS grant accounted for 1.8 of 

the increase in the reported increase in practices. Further, when we 

examined our results from separate regressions for the different 

categories of practices, we found that receipt of a COPS grant was 

associated with significant increases in reported levels of problem-solving 

and place-oriented practices, but was not related to changes in community 

collaboration or crime-analysis practices (table 24). 

Table 24: Parameter Estimates from Regressions of Changes in Mean Number of 

Policing Practices and Category of Practices between 1993 and 1997 on whether or 

Not Agencies Received COPS grant between 1994 and 1997 and on Per Capita 

COPS Expenditures between 1994 and 1997 (Standard Errors in Parentheses) 

 Changes in policing practices from 1993 to 1997 

Independent 

variable in 

model 

All 38 

practices

ProblemsolvingPlaceoriented Crime 

analysis

Community 

collaboration

Regression 1: 

Received COPS 

grant 

1.78

(.732)

.76

(.284)

.78 

(.245) 

.01

(.180)

.25

(.273)

Regression 2: 

COPS 

expenditures per 

capita 

.226

(.080)

.076

(.034)

.086 

(.034) 

.041

(.017)

.023

(.026)

Source: GAO analysis of Policing Strategies Survey, Office of Justice Programs financial, Bureau of Economic Analysis, Census, and 

Uniform Crime Report data 

Notes: All regressions include agency and year fixed effects and changes in county level 

demographic variables (percentage of persons aged 15 to 24, percentage nonwhite, and percentage 

employed) between 1993 and 1997. Observations are weighted to take into account response rates 

and the probability at which the original sampling units were drawn. Bold-face parameter estimates 

and standard errors indicate that a parameter estimate is statistically significant at the 5 percent level. 

Our regression models further show that changes in practices were also 

associated with the cumulative amount of per capita spending on COPS 

grants. All other things being equal, a $1 increase in per capita spending 

was associated with an increase of 0.23 policing practices. As we found for 

the effects of the receipt of a grant on changes in police practices, these 

regressions also showed that the level of per capita spending on COPS 
Appendix VII: Methods Used to Assess 

Policing Practices 

Page 101 GAO-06-104 Community Policing Grants 

grants was significantly associated with increases in problem-solving and 

place-oriented practices. However, per capita spending on COPS grants 

was also significantly associated with increases in crime analysis 

practices. 

The National Evaluation of COPS Survey was conducted by the National 

Opinion Research Center for the Urban Institute in its national evaluation 

of the implementation of the COPS program.5

 The sampling frame for the 

survey consisted of 20,894 law enforcement agencies believed to be in 

existence between June 1993 and June 1997 who had either received a 

COPS grant during 1995 or appeared to be potentially eligible for funding 

but remained unfunded through 1995. The list of COPS grantees was 

obtained from applicant records from the grants management database 

from the COPS Office, and included those agencies that had been funded 

from the following programs: FAST, AHEAD, Universal Hiring Program, 

and MORE. The list of potentially eligible grantees was derived from the 

FBI’s UCR and National Crime Information Center data files. The sampling 

frame was stratified by COPS grantee status (Not Funded, FAST or 

AHEAD, Universal Hiring Program (UHP), MORE), and by population 

(jurisdictions with populations of fewer than 50,000 persons and those 

with populations of 50,000 or more persons), and agencies in each stratum 

were sampled at a different rate in order to select a representative sample 

of law enforcement agencies.6

 A total of 2,098 agencies were selected to be 

in the sample.7

Telephone interviews with agency representatives were conducted in 1996 

(wave 1) and 2000 (wave 4).8 A total of 1,471 agencies responded to wave 1 

 5

See Roth, Jeffrey, et al., National Evaluation of the COPS Program—Title I of the 1994 

Crime Act. 

6

Roth, et al. note that they lacked population data for 4,208 agencies in the sampling frame. 

For sample selection purposes, they treated the missing agencies as a separate stratum. 

However, because inspection indicated that a large majority served jurisdictions of fewer 

than 50,000 persons, these agencies were analyzed in that population category. 

7

Some agencies received more than one type of COPS grant and appeared in more than one 

stratum. The analyses were weighted to take into account the multiple probabilities of 

selection associated with each grant program. 

8

The National Evaluation also conducted two other waves of telephone interviews, in 1997 

and 1998. However, for those surveys, only subsets of the original sample were contacted. 

Characteristics and 

Analysis of the National 

Evaluation of COPS Survey 
Appendix VII: Methods Used to Assess 

Policing Practices 

Page 102 GAO-06-104 Community Policing Grants 

of the survey in 1996, for a 77 percent response rate.9 In 2000, all wave 1 

respondents were recontacted, and interviews were completed with 1,270, 

or 86 percent, of the target agencies. 

We were able to link the data from 1,067 of the agencies that responded to 

both of these waves of the survey to our larger database on crime, officers, 

money, and economic conditions.10 For comparability with the analyses of 

the effects of funding on officers and crime, we excluded from our 

analysis state police agencies, and other “special” police agencies, as well 

as law enforcement agencies serving jurisdictions with populations of 

fewer than 10,000 persons. This resulted in usable data on 724 agencies. 

We used the National Evaluation of COPS Survey to compare levels of 

practices in 1996 and 2000 between groups of agencies that received COPS 

grants and those agencies that were not funded by COPS over this period, 

and to assess changes in reported practices in relation to per capita COPS 

expenditures. The analyses reported in this appendix are weighted to 

adjust for nonresponse and the multiple counting of agencies that received 

more than one COPS grant. The findings are generalizable to all law 

enforcement agencies in the United States serving jurisdictions with 

populations of 10,000 or more persons. 

We used 19 items on policing practices from the National Evaluation of 

COPS Survey, and we classified these items into the same 4 categories of 

practices as we did with the Policing Strategies Survey data (table 25). 

However, because of the shortage of items covering place-oriented 

practices, for analysis purposes we combined these 3 items with the 7 

problem-solving items into one index of problem solving and place 

oriented practices. 

 9

The response rate is not equal to the number of completed interviews of the number of 

agencies because of the possibility of agencies appearing in multiple strata of the sample. 

10These agencies represented about 84 percent of the agencies that responded to both 

waves 1 and 4 of the National Evaluation of COPS Survey 
Appendix VII: Methods Used to Assess 

Policing Practices 

Page 103 GAO-06-104 Community Policing Grants 

Table 25: Categories of Policing Practices and Specific Items within Each Category 

in the National Evaluation of COPS Survey 

Community collaboration 

Regular community meetings to discuss crime 

Surveys of citizens to determine general community needs and satisfaction with 

agency 

Clean-up/fix-up projects with community residents 

Considering neighborhood values in creating solutions or planning projects 

Varying styles of preventive patrol (e.g., bike patrol, walk-and-talk patrol) 

Joint projects with local businesses to reduce disorder or petty crime 

Crime analysis 

Analyzing crime patterns using computerized geographic information systems 

Officers analyze community residents’ comments to identify recurring patterns of 

crime and disorder on their beats 

Officers analyze and use crime data to identify recurring patterns of crime and 

disorder on their beats 

Place-oriented practices 

Joint projects with community residents to reduce disorder such as loitering or public 

drinking 

Beat or patrol boundaries that coincide with neighborhood/community boundaries 

Alcohol, housing, or other code enforcement to combat crime and disorder 

Problem-solving practices 

Designating certain recurring patterns as “problems” or “projects” requiring 

nontraditional responses 

Analyzing problems with business or property owners, school principals, or property 

managers or occupants 

Analyzing problems with probation/parole officers or others who monitor offenders 

Using agency data to measure effects of responses to problems 

Using citizens’ input to measure effects of responses to problems 

Document problems, projects, analyses, responses, failures, and successes in writing 

Making sure problems stay solved 

Source: National Evaluation of COPS Survey, 1996 and 2000. 

Note: Each individual item is coded dichotomously (yes/no) to indicate whether an agency 

implemented the specific practice. 

Unlike the Policing Strategies Survey, which provided a pre-COPS and a 

within-COPS measure of policing practices, both observations (in 1996 and 

2000) on policing practices in the National Evaluation of COPS Survey 

occurred while the COPS program was making grants. This complicates 

our analysis, as in 1996 there were agencies that had already received and 
Appendix VII: Methods Used to Assess 

Policing Practices 

Page 104 GAO-06-104 Community Policing Grants 

spent COPS funds, and to the extent that COPS expenditures were 

associated with the adoption of policing practices, the level of such 

practices that they reported in 1996 would reflect their experiences with 

COPS grants. Some of these agencies continued to spend COPS funds 

throughout the years from 1996 through 2000. However, some of the 

agencies that spent COPS funds in 1996 ceased to spend them during the 

intervening years before 2000. A third group of agencies consists of those 

that had not received their first COPS grant in 1996 but had received a 

grant before 2000. This third group is analogous to our group of agencies 

that received COPS grants in the Policing Strategies survey, with the 

exception that while members of this group received their first COPS grant 

after the first administration of the National Evaluation survey in 1996, 

their practices in 1996 could have been influenced by the COPS program 

indirectly. A final group of agencies is those that did not receive a COPS 

grant before the 1996 administration of the survey or during the years from 

1997 through 2000. 

Because the effects of experience with COPS grants before and after 1996 

could differ, we chose to make two types of comparisons. First, we 

examined the mean changes in policing practices from 1996 to 2000 for 

each of the following groups of agencies: (1) agencies that made 

expenditures on COPS grants in 1994 through 1996, (2) agencies that made 

expenditures on a COPS grant in 1997 through 2000, (3) agencies that 

made no expenditures on a COPS grant after 1996, and (4) agencies that 

made no expenditures on a COPS grant in 1994 through 2000. These mean 

comparisons allowed us to see whether changes in practices were 

associated with receipt of a grant in either the early period of the program 

(through 1996) or when the program was more fully implemented (1997 

through 2000). 

We then examined whether the level of COPS expenditures between the 

two administrations of the survey were associated with changes in 

practices between 1996 and 2000 by regressing the change in practices on 

the change in cumulative per capita COPS expenditures between the 

period preceding wave 1 of the survey (1994 through 1996) and the period 

following wave 1 of the survey (1997 through 2000). As with the Policing 

Strategies Survey, we used two-factor fixed-effects regression techniques, 

which allowed us to control for unobserved characteristics of agencies 

and underlying trends in the adoption of policing practices. We also 

controlled for economic conditions and population changes in the 

localities in which the agencies were located. In addition, we used 

weighted regression to address the complex design of the National 

Evaluation of COPS Survey. We estimated separate regressions of the 
Appendix VII: Methods Used to Assess 

Policing Practices 

Page 105 GAO-06-104 Community Policing Grants 

effect of the receipt of a COPS grant and of the cumulative per capita 

amount of COPS expenditures on the levels of reported policing practices. 

There were no significant differences in the overall adoption of policing 

practices associated with changes in per capita spending on COPS grants 

(table 26). 

Table 26: Parameter Estimates from Regressions of Changes in Mean Number of 

Policing Practices and Category of Practices between 1996 and 2000 on Whether or 

Not Agencies Received COPS grant Between 1997 and 2000 and on Per Capita 

COPS Expenditures between 1994-1996 and 1997-2000 (Standard Errors in 

Parentheses) 

 Changes in policing practices from 1996 to 2000 

Independent 

variable in model 

All 19 

practices

Problemsolving and 

PlaceorientedCrime 

analysis

Community 

collaboration

Changes in COPS 

expenditures per 

capita between 

1994-1996 and 

1997-2000 

.056

(.032)

.030

(.021)

.011

(.008)

.016

(.008)

Source: GAO analysis of National Evaluation of COPS Survey, Office of Justice Programs financial, Bureau of Economic Analysis, 

Census, and Uniform Crime Report data 

Notes: All regressions include agency and year fixed effects and changes in county level 

demographic variables (percentage of persons aged 15 to 24, percentage nonwhite, and percentage 

employed) between 1996 and 2000. Observations are weighted to take into account sample design 

effects. Bold-face parameter estimates and standard errors indicate that a parameter estimate is 

statistically significant at the 5 percent level. 

To determine whether the certain types of policing practices may be 

effective in reducing crime, we analyzed systematic reviews of research 

studies on the effectiveness of policing practices. 

We identified six studies that provided summaries of research on the 

effectiveness of policing practices on reducing crime. We chose to review 

studies that reviewed research, rather than reviewing all of the original 

studies themselves, because of the volume of studies that have been 

conducted on the effectiveness of policing practices. We reviewed the 

following studies: 

• Braga, Anthony. “Effects of Hot Spots Policing on Crime,” Annals, 

AAPSS, vol. 578 (November 2001), pp. 104-125. 

Methods to Review 

Policing Practices 

How We Selected Studies 
Appendix VII: Methods Used to Assess 

Policing Practices 

Page 106 GAO-06-104 Community Policing Grants 

• Eck, John. “Preventing Crime at Places” in Sherman, L., et al. (eds.) 

Preventing Crime: What Works, What Doesn’t, What’s Promising: A 

Report to the United States Congress. Washington, D.C.: National 

Institute of Justice, 1998. 

• Eck, John, and Edward Maguire. “Have Changes in Policing Reduced 

Violent Crime? An Assessment of the Evidence.” in Blumstein, A., and 

J. Wallman, eds., The Crime Drop in America. United Kingdom: 

Cambridge University Press, 2000. 

• Sherman, Lawrence. “Policing for Crime Prevention,” in Sherman, L., et 

al. (eds.) Preventing Crime: What Works, What Doesn’t, What’s 

Promising: A Report to the United States Congress. Washington, D.C.: 

National Institute of Justice, 1998. 

• Skogan, Wesley, and Kathleen Frydl. “The Effectiveness of Police 

Activities in Reducing Crime, Disorder, and Fear,” in Skogan, W., and K. 

Frydl, (eds.) Fairness and Effectiveness in Policing: The Evidence,

Washington, D.C.: National Academies Press, pp. 217-251, 2004. 

• Weisburd, David, and John Eck. “What Can Police Do to Reduce Crime, 

Disorder, and Fear?” Annals, AAPSS, Vol. 593 (November 2004), pp. 42-

65. 

A limitation of basing our work on reviews is that we did not assess the 

original studies, but rather we relied on the descriptions and assessments 

as provided by the authors of the reviews. Sometimes the reviews did not 

cite specific information about the strength of the methodology of the 

underlying studies that were included in reviews. 

We developed a data collection instrument to capture systematically 

information about the methodologies of the reviews, the types of policing 

practices reviewed, findings about each type of practice, and the 

reviewers’ conclusions about the effectiveness of a particular practice or 

group of practices in reducing crime. Each research review was read and 

coded by a social science analyst who had training and experience in 

reviewing research methodologies. This analyst recorded, for each 

practice discussed in the research review, (1) the types of crimes against 

which the practices were used (e.g., all crimes, violent crimes, property 

crimes, disorder); (2) whether the practice was generally effective in 

reducing crime, had no effect in reducing crime, or the impact was 

ambiguous; (3) whether there was displacement of crimes away from the 

How We Reviewed Studies 
Appendix VII: Methods Used to Assess 

Policing Practices 

Page 107 GAO-06-104 Community Policing Grants 

areas where the practices were used; and (4) whether there were negative 

effects of the practices (e.g., complaints against the police or the diversion 

of resources from other policing activities). A second, similarly trained 

analyst then read the reviews and verified the accuracy of the information 

recorded by the first analyst. We then summarized the findings about each 

practice from the data collection instruments prepared for each of the six 

reviews. Some practices were discussed in only one review, while others 

were discussed in more than one review. 

Our analysis of six systematic reviews of evaluations of the effectiveness 

of various policing practices in preventing crime indicates that the current 

evidence ranges from moderate to strong that problem-oriented policing 

practices and place-oriented practices are either effective or promising as 

strategies for addressing crime problems. For example, problem-oriented 

approaches that focus on criminogenic substances such as guns and drugs 

appear to be effective in reducing both violent and property crimes. And 

hot spots approaches—place-oriented approaches that temporarily apply 

police resources to discrete locations where crime is concentrated at 

much higher rates than occurs jurisdictionwide—have also been found to 

be effective in reducing crime. However, the magnitudes of the effects of 

these interventions are difficult to estimate, especially on citywide crime 

rates, as the interventions that were reviewed as effective generally were 

concentrated in comparatively small places. Further, the enduring nature 

of these interventions is not fully understood. It is not known, for example, 

how long the effects of a problem- or place-oriented intervention persist. 

In addition, some of the reviews point out that research designs 

undertaken to date make it difficult to disentangle the effects of problemoriented policing from hot spots policing. There is suggestive, but limited, 

evidence that the combination of these practices may be more effective in 

preventing or reducing crime than any one strategy alone. 

In contrast to the findings on problem-oriented and place-oriented policing 

practices, there is little evidence in the literature for the effectiveness of 

community collaboration practices—such as increasing foot patrol, 

establishing community partnerships, and encouraging citizen 

involvement—in reducing or preventing crime. 

The Research Literature 

Shows That Some Policing 

Practices May be Effective 

in Reducing Crime 
Appendix VIII: Comments from the 

Department of Justice 

Page 108 GAO-06-104 Community Policing Grants 

Appendix VIII: Comments from the 

Department of Justice 
Appendix VIII: Comments from the 

Department of Justice 

Page 109 GAO-06-104 Community Policing Grants 
Appendix VIII: Comments from the 

Department of Justice 

Page 110 GAO-06-104 Community Policing Grants 
Appendix VIII: Comments from the 

Department of Justice 

Page 111 GAO-06-104 Community Policing Grants 
Appendix IX: GAO Contacts and Staff 

Acknowledgments 

Page 112 GAO-06-104 Community Policing Grants 

Laurie E. Ekstrand (202) 512-8777 

Nancy R. Kingsbury (202) 512-2700 

In addition to those named above the following individuals made key 

contributions to this report: William J. Sabol, Tom Jessor, David R. Lilley, 

Benjamin A. Bolitzer, George H. Quinn, Jr., and Grant M. Mallie. Others 

contributing included David P. Alexander, Harold J. Brumm Jr., Scott 

Farrow, Kathryn E. Godfrey, Adam T. Hatton, Ronald La Due Lake, 

Terence C. Lam, and Robert Parker. 

Appendix IX: GAO Contacts and Staff 

Acknowledgments 

GAO Contacts 

Acknowledgments 
Bibliography 

Page 113 GAO-06-104 Community Policing Grants 

Attorney General of the United States. Report to Congress: Office of 

Community Oriented Policing Services, Washington, D.C.: U.S. 

Department of Justice, September 2000. 

Blumstein, Alfred, and Joel Wallman (eds.). The Crime Drop in America,

Cambridge, England: Cambridge University Press, 2000. 

Braga, Anthony. “Effects of Hot Spots Policing on Crime,” Annals, AAPSS, 

vol. 578 (November 2001), pp. 104-125. 

Cook, Philip. “The Clearance Rate as a Measure of Criminal Justice System 

Effectiveness,” Journal of Public Economics, vol. 11, 1979, pp. 135-142. 

Davis, Gareth, et al. “The Facts about COPS: A Performance Overview of 

the Community Oriented Policing Services Program,” Washington, D.C.: 

The Heritage Foundation, September 25, 2000. 

Di Tella, Rafael and Ernesto Schargrodsky. “Do Police Reduce Crime? 

Estimates Using the Allocation of Police Forces after a Terrorist Attack.” 

American Economic Review. March 2004, 94(1). pp. 115-133. 

Dunworth, Terence, Peter Haynes, and Aaron J. Saiger. National 

Assessment of the Byrne Formula Grant Program, Washington, D.C.: 

National Institute of Justice Research Report, June 1997. 

Eck, John. “Preventing Crime at Places” in Sherman, L., et al. (eds.) 

Preventing Crime: What Works, What Doesn’t, What’s Promising: A 

Report to the United States Congress. Washington, D.C.: National Institute 

of Justice, 1998. 

Eck, John and Edward Maguire. “Have Changes in Policing Reduced 

Violent Crime? An Assessment of the Evidence.” in Blumstein, A., and J. 

Wallman, eds., The Crime Drop in America. United Kingdom: Cambridge 

University Press, 2000. 

Ehrlich, Isaac. “Participation in Illegitimate Activities: A Theoretical and 

Empirical Investigation.” Journal of Political Economy, May June, 81(3), 

pp. 521-65 (1973). 

Evans, William N., and Emily Owens. “Flypaper COPS,” College Park, 

Maryland.: University of Maryland. Available online 

www.bsos.umd.edu/econ/evans/wpapers/Flypaper%20COPS.pdf., 2005. 

Bibliography 
Bibliography 

Page 114 GAO-06-104 Community Policing Grants 

Executive Office of the President. Performance and Management 

Assessments: Budget of the United States, Fiscal Year 2004, Washington, 

D.C.: The White House, 2003. 

Federal Bureau of Investigation, Crime in the United States, 2002, 

Uniform Crime Reports, Washington, D.C.: U.S. Department of Justice. 

Printed annually. 

GAO, Technical Assessment of Zhao and Thurman’s 2001 Evaluation of 

the Effects of COPS Grants on Crime, GAO-03-867R (Washington, D.C.: 

June 13, 2003). 

Johnson, Calvin C., and Jeffrey A. Roth, The COPS Program and the 

Spread of Community Policing Practices, 1995-2000. Washington, D.C.: 

The Urban Institute, June 2003. 

Klick, Jonathan, and Alexander Tabarrok. “Using Terror Alert Levels to 

Estimate the Effect of Police on Crime.” Journal of Law and Economics, 

April, Vol. XLVIII (2005). 

Koper, Christopher S., et al. Putting 100,000 Officers on the Street: A 

Survey-Based Assessment of the Federal COPS Program, Washington, 

D.C.: The Urban Institute, October 2002. 

Levitt, Steven D. “The Effect of Prison Population Size on Crime Rates: 

Evidence from Prison Overcrowding Litigation” Quarterly Journal of 

Economics, 111 No. 2. (May, 1996). 

Levitt, Steven D. “Using Electoral Cycles in Police Hiring to Estimate the 

Effect of Police on Crime.” American Economic Review 87 (1997): 270-

290. 

Levitt, Steven D., “The Relationship between Crime Reporting and Police: 

Implications for the Use of Uniform Crime Reports,” Journal of 

Quantitative Criminology, Vol. 14, No. 1998: pp. 61-81. 

Levitt, Steven D. “Using Electoral Cycles in Police Hiring to Estimate the 

Effects of Police on Crime: Reply” American Economic Review, 

September 2002, 92(4), pp. 1,244-50. 

Lynch, James P., “Exploring the Sources of Non-response in the Uniform 

Crime Reports: Things to Do Before Multiple Imputation.” Paper presented 
Bibliography 

Page 115 GAO-06-104 Community Policing Grants 

at the Annual Meetings of the American Society of Criminology Research 

Conference, November 19, 2003. 

Marvell, Thomas, and Carlisle Moody. “Specification Problems, Police 

Levels, and Crime Rates.” Criminology 1996, Vol., No. 4, pp. 609-46. 

McCrary, Justin. “Using Electoral Cycles in Police Hiring to Estimate the 

Effect of Police on Crime: Comment.” American Economic Review. 

September 2002, 92(4), pp. 1,236-43. 

National Center for Health Statistics. Estimates of the July 1, 2000—July 1, 

2003, United States resident population from the Vintage 2003 postcensal 

series by year, county, age, sex, race, and Hispanic origin, prepared under 

a collaborative arrangement with the U.S. Census Bureau. Available on the 

Internet at 

http://www.cdc.gov/nchs/about/major/dvs/popbridge/popbridge.htm. 

September 14, 2004. 

Rosenthal, Arlen M., and Lorie Fridell. National Survey of Community 

Policing Strategies Update, 1997, and Modified 1992-1993 Data [Computer 

file]. Inter-university Consortium for Political and Social Research (ICPSR) 

version. Calverton, Maryland: ORC Macro International, Inc. [producer], 

2002. Ann Arbor, Michigan: ICPSR [distributor], 2002. 

Roth, Jeffrey, et al. National Evaluation of the COPS Program—Title I of 

the 1994 Crime Act, Washington, D.C.: National Institute of Justice, 

August 2000. 

Sherman, Lawrence. “Policing for Crime Prevention,” in Sherman, L., et al. 

(eds.) Preventing Crime: What Works, What Doesn’t, What’s Promising: 

A Report to the United States Congress. Washington, D.C.: National 

Institute of Justice, 1998. 

Skogan, Wesley, and Kathleen Frydl. “The Effectiveness of Police 

Activities in Reducing Crime, Disorder, and Fear,” in Skogan, W., and K. 

Frydl, (eds.) Fairness and Effectiveness in Policing: The Evidence,

Washington, D.C.: National Academies Press, pp. 217-251, 2004. 

Swimmer, Eugene. “The Relationship of Police and Crime: Some 

Methodological and Empirical Results,” Criminology, vol. 12, 1974: pp. 

293-314. 
Bibliography 

Page 116 GAO-06-104 Community Policing Grants 

Weisburd, David, and John Eck. “What Can Police Do to Reduce Crime, 

Disorder, and Fear?” Annals, AAPSS, vol. 593 (May 2004), pp. 42-65. 

Wycoff, Mary Ann, Community Policing Strategies: A Comprehensive 

Analysis, Washington, D.C.: The Police Foundation, November 1994. 

Zhao, J., and Q. Thurman. A National Evaluation of the Effect of COPS 

Gants on Crime from 1994 to 1999. Report submitted to the Office of 

Community Oriented Policing Services, Washington, D.C.: U.S. Department 

of Justice, December 2001. 

Zhao, J., and Q. Thurman. Funding Community Policing to Reduce 

Crime: Have COPS Grants Made a Difference from 1994 to 2000? Report 

submitted to the Office of Community Oriented Policing Services, 

Washington, D.C.: U.S. Department of Justice, July 2004. 

(440258) 
The Government Accountability Office, the audit, evaluation and 

investigative arm of Congress, exists to support Congress in meeting its 

constitutional responsibilities and to help improve the performance and 

accountability of the federal government for the American people. GAO 

examines the use of public funds; evaluates federal programs and policies; 

and provides analyses, recommendations, and other assistance to help 

Congress make informed oversight, policy, and funding decisions. GAO’s 

commitment to good government is reflected in its core values of 

accountability, integrity, and reliability. 

The fastest and easiest way to obtain copies of GAO documents at no cost 

is through GAO’s Web site (www.gao.gov). Each weekday, GAO posts 

newly released reports, testimony, and correspondence on its Web site. To 

have GAO e-mail you a list of newly posted products every afternoon, go 

to www.gao.gov and select “Subscribe to Updates.” 

The first copy of each printed report is free. Additional copies are $2 each. 

A check or money order should be made out to the Superintendent of 

Documents. GAO also accepts VISA and Mastercard. Orders for 100 or 

more copies mailed to a single address are discounted 25 percent. Orders 

should be sent to: 

U.S. Government Accountability Office 

441 G Street NW, Room LM 

Washington, D.C. 20548 

To order by Phone: Voice: (202) 512-6000 

TDD: (202) 512-2537 

Fax: (202) 512-6061 

Contact: 

Web site: www.gao.gov/fraudnet/fraudnet.htm 

E-mail: fraudnet@gao.gov

Automated answering system: (800) 424-5454 or (202) 512-7470 

Gloria Jarmon, Managing Director, JarmonG@gao.gov (202) 512-4400 

U.S. Government Accountability Office, 441 G Street NW, Room 7125 

Washington, D.C. 20548 

Paul Anderson, Managing Director, AndersonP1@gao.gov (202) 512-4800 

U.S. Government Accountability Office, 441 G Street NW, Room 7149 

Washington, D.C. 20548 

GAO’s Mission 

Obtaining Copies of 

GAO Reports and 

Testimony 

Order by Mail or Phone 

To Report Fraud, 

Waste, and Abuse in 

Federal Programs 

Congressional 

Relations 

Public Affairs 

PRINTED ON RECYCLED PAPER