Number 347 May 2008

Traffic Safety Facts

Traffic Tech – Technology Transfer Series

U.S. Department of Transportation 1200 New Jersey Avenue SE., Washington, DC 20590

National Highway Traffic Safety Administration

The Effectiveness of Seven Publicized Enforcement 

Demonstration Programs to Reduce Impaired 

 Driving: Georgia, Louisiana, Pennsylvania, 

 Tennessee, Indiana, Michigan, and Texas

In 2006, preliminary data from NHTSA indicates that more

than 17,000 people died in alcohol-related crashes. Prior

NHTSAresearch and demonstration studies have resulted in

increased seat belt usage and a reduction in alcohol-related

crashes. Some of these programs (Click It or Ticket) have

involved short-term mobilizations or blitzes while others

(Checkpoint Tennessee) involved both blitzes and longer

term enforcement efforts. Both kinds of programs have common elements, that is, the coupling of increased and highly

visible enforcement with intense publicity about the enforcement program. It thereby seemed logical that a similar strategy could reduce impaired driving when applied to a larger

number of States.

Between 2000 and 2003, NHTSA funded seven alcohol

demonstration programs designed to reduce impaired

driving through well-publicized and highly visible enforcement. These demonstration programs were not specifically

designed to be research evaluation studies; instead, they

were designed to reduce drinking-and-driving behavior and

ultimately alcohol-related crashes. The States varied widely

in their enforcement methods, media methods, and their

paid and earned media budgets and messages.

Four of the programs (GA, TN, IN, MI) were conducted

statewide or nearly statewide. Paid advertising was used in

Georgia, Indiana, and Michigan. In Georgia, Tennessee, Indiana, and Pennsylvania sobriety checkpoints were conducted

throughout the data collection period. In Louisiana checkpoints were permitted part way through data collection, and

in Texas and Michigan checkpoints were not permitted. The

number and types of enforcement activities varied considerably from State to State. Georgia reported using 2,837 checkpoints. Pennsylvania used checkpoints, mobile awareness

patrols, and roving patrols yielding more than 1,100 roadside

enforcement actions, while Tennessee used a combination of

checkpoints (535), enforcement roadblocks (approximately

270), and saturation patrols (270). Michigan used 1,122 saturation and routine patrols, and in Indiana more than 3,800

patrol hours were reported. The number of DUI or DWI

arrests varied considerably, typically varying from a few

hundred to a few thousand.

Survey Findings In five of the seven States (GA, LA, PA,

TN, and TX) one random digit dial telephone survey wave

of 1,000 drivers was conducted before program implementation, one wave of 1,000 drivers was conducted midway

through the program, and a third wave was conducted at the

completion of the program. Due to logistical reasons, similar

surveys in Indiana and Michigan were not conducted so the

impact of their paid advertising is less well understood.

For one of these States—Georgia—there was a positive

change in awareness of the enforcement program and a positive change in self-reported behavior. None of the other four

States employing essentially the same survey showed positive changes in self-reported behavior.

In general, the findings from the driver surveys in the five

States were disappointing. It was thought that the increased

media andenforcementprogramwouldbe associatedwithan

increase in awareness of the enforcement program, a reduction in driving after drinking behavior, as well as an increase

in the perception of being stopped by the police for an alcohol offense and arrested if over the limit. Such changes in

awareness, perceptions, and self-reported behavior did not

occur to a significant extent in any of the States.

Impact Analysis: Time series analyses (ARIMA) were used

to determine if the ratio of drinking drivers to non-drinking

drivers involved in fatal crashes experienced changes during

the enforcementprogram. NHTSA’s FatalityAnalysisReporting System (FARS) was used in the analyses with neighboring States serving as comparisons. This ratio was also used

in comparing the intervention counties to non-intervention

counties.In addition, alcohol-relatedfatalities were expressed

in a ratio relative to annual vehicle miles traveled (VMT).
As compared to neighboring States, Georgia showed a statistically significant decrease (14%; p<.005) in the ratio of drinking drivers to non-drinking drivers. Using this measure, an

estimated 60 lives were saved in the first year associated with

the Georgia program. A non-significant 5-percent decrease

was found in alcohol-related fatalities per 100 million VMT.

Louisiana experienced decreases in their intervention counties, but compared to the non-intervention counties and

neighboring States, significant decreases were not obtained;

in fact, relative to their neighboring States, a significant

increase was obtained. Although Pennsylvania showed

decreases in the driver ratio measure for intervention and

nonintervention counties versus neighboring States, none

were statistically significant. Tennessee experienced a significant decrease (-10.6%, p<0.35) in the driver ratio relative

to neighboring States and no significant change in alcoholrelated fatalities per 100 million VMT. In Texas, the 14 intervention counties showed no significant change in the ratio

of drinking drivers to non-drinking drivers involved in fatal

crashes nor in the alcohol-related fatality rate. The intervention counties in Indiana experienced a statistically significant

decrease of 13 percent (p<.02) in the ratio of drinking drivers

to non-drinking drivers involved in fatal crashes and a 20-

percent decrease (p<.002) in alcohol-related fatalities per 100

million VMT. Indiana also experienced significant decreases

in the nonintervention counties compared to neighboring

States. Using the drinking driver ratio measure, it was estimated that 25 lives were saved in the intervention counties

and 17 in the rest of the State. Also, Michigan experienced a

14-­percent decrease (p<.07) in the ratio of drinking drivers to

non-drinking drivers involved in fatal crashes in the intervention counties compared to neighboring States. This resulted

in an estimated 57 lives saved during the program. Michigan

also experienced a significant decrease of 18 percent (p<.003)

in alcohol-related fatalities per 100 million VMT.

A major finding concerned the use of paid advertising. Three

of the four States (GA, IN, MI) demonstrating a decrease in

drinking driver fatal crashes used paid advertising.

In summary, it appears that a variety of media and enforcement procedures that supplement ongoing statewide efforts

can yield meaningful crash reduction effects among alcohol impaired drivers. In general, States employing sobriety

checkpoints, using paid advertising and programs implemented statewide were associated with crash reductions relative to surrounding States. In addition, the use of saturation

patrols alone may result in crash reduction.

Also, as each of these demonstration programs was unique

and superimposed on existing State program activities targeting drinking drivers, simple relationships were not obtained

between crash reductions and (a) amount, type, and target

of publicity campaigns; (b) amount and type of enforcement activities; and (c) driver awareness, perceptions, and

self-reported behavior. Based upon previous research and

some of the implications from this study, a State impaired

driving enforcement program is more likely to be successful

if it incorporates (a) numerous checkpoints or highly visible

saturation patrols conducted routinely throughout the year

along with mobilized crackdowns (at least two per year); and

(b) intensive publicity coverage of the enforcement activities,

including paid advertising.

The results from these seven high-visibility enforcement

demonstration programs have helped shape NHTSA’s current annual Over the Limit. Under Arrest. national crackdown

mobilization around Labor Day and in December. The lessons

learned include the need for sustained high-visibility enforcement, for sufficient enforcement efforts that create the impression of increased risk of detection by impaired drivers, and

the need for intensive publicity about the increased enforcement activity that reaches the impaired driver population.

How To order: Evaluation of Seven Publicized Enforcement 

Demonstration Programs to Reduce Impaired Driving: 

Georgia, Louisiana, Pennsylvania, Tennessee, Texas, Indiana, and Michigan (137 pages plus appendices), write to the

Office of Behavioral Safety Research, NHTSA, NTI-130, 1200

New Jersey Avenue SE., Washington, DC 20590, fax 202-366-

2766, or download from www.nhtsa.dot.gov. Marvin Levy,

Ph.D. was the Contracting Officer’s Technical Representative for this project.

TRAFFIC TECH is a publication to disseminate information about

traffic safety programs, including evaluations, innovative programs, and new publications. Feel free to copy it as you wish. If you

would like to receive a copy, contact Patricia Ellison-Potter, Ph.D.,

Editor, fax 202-366-7096, e-mail: traffic.tech@dot.gov.

1200	New	Jersey	Avenue	SE.,	NTI-130

Washington,	DC	20590