NOTICE

This document is disseminated under the sponsorship of the U.S. Department of Transportation 

(USDOT) in the interest of information exchange. The U.S. Government assumes no liability for 

the use of the information contained in this document. This report does not constitute a standard, 

specification, or regulation. The U.S. Government does not endorse products or manufacturers. 

Trademarks or manufacturers’ names appear in this report only because they are considered 

essential to the objective of the document.

QUALITY ASSURANCE STATEMENT

The Federal Highway Administration (FHWA) provides high-quality information to serve 

Government, industry, and the public in a manner that promotes public understanding. Standards 

and policies are used to ensure and maximize the quality, objectivity, utility, and integrity of its 

information. FHWA periodically reviews quality issues and adjusts its programs and processes 

to ensure continuous quality improvement.

Source, Cover: photo courtesy of KC Scout and the Kansas City Police Department
Crash Investigation and Reconstruction i U.S. Department of Transportation 

Technologies and Best Practices Federal Highway Administration

TECHNICAL REPORT DOCUMENTATION PAGE

1. Report No.

FHWA-HOP-16-009

2. Government Accession No. 3. Recipient’s Catalog No.

4. Title and Subtitle

Crash Investigation and Reconstruction Technologies and Best

Practices

5. Report Date

October 2015

6. Performing Organization

Code

7. Author(s)

William James, Steve McKinzie, William Benson, Cliff Heise

8. Performing Organization

Report No.

9. Performing Organization Name and Address

Iteris, Inc.

107 Carpenter Drive, Suite 230

Sterling, VA 20164

Subconsultants: Gannett Fleming

10. Work Unit No. (TRAIS)

11. Contract or Grant No.

Contract No.

DTFH61-12-D-00037

Task Order No. 5009

12. Sponsoring Agency Name and Address

Federal Highway Administration

Office of Operations

1200 New Jersey Avenue SE

Washington, DC 20590

13. Type of Report and Period

Covered

Informational Guide Book

August 2014 - September

2015

14. Sponsoring Agency Code

FHWA HOP

15. Supplementary Notes

Paul Jodoin, FHWA GTM

16. Abstract

Traffic crashes have an effect on the lives of those involved, the lives of those who respond to the

incident and the lives of those who investigate the incident. The collection of evidence at a crash

scene is very important but the exposure of responders to the dangers of traffic increases the chance

of a secondary collision occurring. When technology is effectively applied to traffic incident

management and crash investigation, safety is increased and traffic congestion is minimized. The

use of traffic crash reconstruction technology has a significant impact on the safety of the

investigators, the traveling public and the operation of the transportation system. This report

examines available crash investigation and reconstruction technology. The evolution of traffic

crash reconstruction technology has introduced many new types of equipment to this field, as well

as constantly evolving innovations. The report provides information about each technology’s

capabilities and limitations to inform crash investigation units of the options available.

17. Key Words

Crash, reconstruction, investigation, incident,

accident, traffic incident management, safety

18. Distribution Statement

No restrictions.

19. Security Classif. (or this

report)

Unclassified

20. Security Classif. (of this

page)

Unclassified

21. No. of Pages

80

22. Price

Form DOT F1700.7 (8-72) Reproduction of completed pages authorized
Crash Investigation and Reconstruction ii U.S. Department of Transportation

Technologies and Best Practices Federal Highway Administration

METRIC CONVERSION CHART

APPROXIMATE CONVERSIONS TO SI UNITS

SYMBOL WHEN YOU KNOW MULTIPLY BY TO FIND SYMBOL

LENGTH

in inches 25.4 millimeters mm

ft feet 0.305 meters m

yd yards 0.914 meters m

mi miles 1.61 kilometers km

AREA

in2 square inches 645.2 square millimeters mm2

ft2 square feet 0.093 square meters m2

yd2 square yard 0.836 square meters m2

ac acres 0.405 hectares ha

mi2 square miles 2.59 square kilometers km2

TEMPERATURE (exact degrees) o

F Fahrenheit 5 (F-32)/9

or (F-32)/1.8

Celsius oC

ILLUMINATION

fc foot-candles 10.76 lux lx

fl foot-Lamberts 3.426 candela/m2 cd/m2

APPROXIMATE CONVERSIONS FROM SI UNITS

SYMBOL WHEN YOU KNOW MULTIPLY BY TO FIND SYMBOL

LENGTH

mm millimeters 0.039 inches in

m meters 3.28 feet ft

m meters 1.09 yards yd

km kilometers 0.621 miles mi

AREA

mm2 square millimeters 0.0016 square inches in2

m2 square meters 10.764 square feet ft2

m2 square meters 1.195 square yards yd2

ha hectares 2.47 acres ac

km2 square kilometers 0.386 square miles mi2

TEMPERATURE (exact degrees) o

C Celsius 1.8C+32 Fahrenheit o

F

ILLUMINATION

lx lux 0.0929 foot-candles fc

cd/m2 candela/m2 0.2919 foot-Lamberts fl
Crash Investigation and Reconstruction iii U.S. Department of Transportation

Technologies and Best Practices Federal Highway Administration

TABLE OF CONTENTS

EXECUTIVE SUMMARY .......................................................................................................... 1

CHAPTER 1 INTRODUCTION............................................................................................... 5

PROGRESSION OF LAW ENFORCEMENT INVESTIGATION TECHNOLOGY .............. 6

TRAFFIC CRASH RECONSTRUCTION 101.......................................................................... 8

RELATIONSHIP BETWEEN CRASH RECONSTRUCTION AND TRAFFIC INCIDENT 

MANAGEMENT........................................................................................................................ 9

CHAPTER 2 INPUT FROM EXPERIENCED CRASH RECONSTRUCTION 

PROFESSIONALS ..................................................................................................................... 11

RESEARCH OF PRACTICES AND TECHNOLOGIES........................................................ 13

FUNDING DECISIONS........................................................................................................... 14

BEST PRACTICES .................................................................................................................. 14

CHAPTER 3 RESEARCH METHODOLOGY .................................................................... 15

SURVEY OVERVIEW ............................................................................................................ 15

CHAPTER 4 RESEARCH RESULTS ................................................................................... 17

CHAPTER 5 TECHNOLOGY OVERVIEW........................................................................ 19

MECHANICAL MEASUREMENT TOOLS .......................................................................... 19

ELECTRONIC TOTAL STATION ......................................................................................... 21

REFLECTORLESS ELECTRONIC TOTAL STATION ........................................................ 23

SEMI-ROBOTIC TOTAL STATION...................................................................................... 26

ROBOTIC TOTAL STATION................................................................................................. 29

TOTAL STATION HYBRID................................................................................................... 32

CLOSE-RANGE PHOTOGRAMMETRY .............................................................................. 35

THREE-DIMENSIONAL LASER SCANNING ..................................................................... 38

UNMANNED AERIAL SYSTEMS......................................................................................... 41

GLOBAL POSITIONING SYSTEMS..................................................................................... 44

LIGHT DETECTION AND RANGING SYSTEMS............................................................... 46

IMAGING STATIONS ............................................................................................................ 48

CHAPTER 6 VIRTUAL DEMONSTRATIONS................................................................... 51

CHAPTER 7 CONCLUSIONS ............................................................................................... 53

APPENDIX A: EXPERT PANEL BIOGRAPHIES................................................................ 55

APPENDIX B: TECHNOLOGY RANKINGS ........................................................................ 63

RANKING IN ORDER ............................................................................................................ 63

COURT ACCEPTANCE.......................................................................................................... 69
Crash Investigation and Reconstruction iv U.S. Department of Transportation

Technologies and Best Practices Federal Highway Administration

COST ........................................................................................................................................ 70

BIBLIOGRAPHY....................................................................................................................... 71

LIST OF FIGURES

Figure 1. Graph. Traffic Incident Management Event Sequence ................................................... 5

Figure 2. Graph. Expert Panel Members' Geographic Distribution.............................................. 11

Figure 3. Photo. Mechanical Measurement Tool.......................................................................... 20

Figure 4. Photo. Electronic Total Station...................................................................................... 22

Figure 5. Photo. Reflectorless Total Station ................................................................................. 25

Figure 6. Photo. Semi-Robotic Total Station................................................................................ 28

Figure 7. Photo. Robotic Total Station ......................................................................................... 31

Figure 8. Photo. Total Station Hybrid........................................................................................... 34

Figure 9. Photo. Photogrammetry................................................................................................. 37

Figure 10. Photo. Three-dimensional Laser Scanning.................................................................. 40

Figure 11. Photo. Unmanned Aerial Systems............................................................................... 43

Figure 12. Photo. Global Positioning Systems ............................................................................. 45

Figure 13. Photo. Light Detection and Ranging Systems............................................................. 47

Figure 14. Photo. Imaging Stations............................................................................................... 50
Crash Investigation and Reconstruction v U.S. Department of Transportation

Technologies and Best Practices Federal Highway Administration

LIST OF TABLES

Table 1. Technology Rating Criteria .............................................................................................. 2

Table 2. Research Summary ........................................................................................................... 3

Table 3. Crash Reconstruction Technology and Best Practice Panelists...................................... 12

Table 4. Technology Rating Criteria ............................................................................................ 17

Table 5. Mechanical Measurement Tools Equipment and Costs.................................................. 19

Table 6. How the Experts Rated Mechanical Measurement Tools............................................... 20

Table 8. Electronic Total Station Equipment and Costs............................................................... 21

Table 9. How the Experts Rated Electronic Total Station............................................................ 22

Table 11. Reflectorless Electronic Total Station Equipment and Costs....................................... 23

Table 12. How the Experts Rated Reflectorless Total Station...................................................... 25

Table 14. Semi-Robotic Equipment and Costs............................................................................. 26

Table 15. How the Experts Rated Semi-Robotic Total Station .................................................... 28

Table 17. Robotic Total Station Equipment and Costs................................................................. 29

Table 18. How the Experts Rated Robotic Total Station.............................................................. 31

Table 20. Total Station Hybrid Equipment and Costs.................................................................. 32

Table 21. How the Experts Rated Total Station Hybrid ............................................................... 34

Table 23. Photogrammetry Equipment and Costs........................................................................ 35

Table 24. How the Experts Rated Photogrammetry ..................................................................... 37

Table 26. Three-dimensional Laser Scanning Equipment and Costs........................................... 38

Table 27. How the Experts Rated Three-dimensional Laser Scanning ........................................ 40

Table 29. Unmanned Aerial Systems Equipment and Costs........................................................ 42

Table 30. How the Experts Rated Unmanned Aerial Systems ..................................................... 43

Table 32. Global Positioning System Equipment and Costs........................................................ 44

Table 33. How the Experts Rated GPS Systems........................................................................... 45

Table 35. Light Detection and Ranging Systems Equipment and Costs...................................... 46

Table 36. How the Experts Rated Light Detection and Ranging Systems ................................... 47

Table 38. Imaging Stations Equipment and Costs........................................................................ 48

Table 39. How the Experts Rated Imaging Stations..................................................................... 50
Crash Investigation and Reconstruction vi U.S. Department of Transportation

Technologies and Best Practices Federal Highway Administration

LIST OF ABBREVIATIONS AND SYMBOLS

2-D – Two-dimensional

3-D – Three-dimensional

A&M – Agricultural and Mechanical

ACTAR - Accreditation Commission for Traffic Accident Reconstruction

AGL – Above Ground Level

AGPS – Assisted Global Positioning System

CAD – Computer Aided Diagramming

CAR – Collision Analysis Reconstruction

COA – Certificates of Authorization

DGPS – Differential Global Positioning System

DOD – Department of Defense

DOT – Department of Transportation

DUI – Driving Under the Influence

EDM – Electronic Distance Measurement Instrument

FAA – Federal Aviation Administration

FHWA – Federal Highway Administration

GCP – Ground Control Point

GLONASS - Global Navigation Satellite System

GNSS – Global Navigation Satellite System

GPS – Global Positioning System

HD – High-Definition

IACP – International Association of Chiefs of Police

IPTM - Institute of Police Technology and Management

ITS – Intelligent Transportation Systems

LiDAR – Light Detection and Ranging

N/A – Not Applicable

NAS – National Air Space

NTSB – National Transportation Safety Board

NUG – National Unified Goal

OEM – Original Equipment Manufacturer

RMT – Remote Measuring Target

RTK – Real Time Kinematic

SAE – Society of Automotive Engineers

SLR – Single-Lens Reflex

TCRU - Traffic Crash Reconstruction Unit

TIM – Traffic Incident Management

UAS – Unmanned Aerial System

WAAS – Wide Area Augmentation System
Crash Investigation and Reconstruction 1 U.S. Department of Transportation

Technologies and Best Practices Federal Highway Administration

EXECUTIVE SUMMARY

Crash investigators have been reconstructing the circumstances surrounding traffic crashes since 

the first crash involving the automobile occurred. Investigations are carried out by law 

enforcement investigators and private crash professionals. While the majority of traffic crashes 

involve human error on the part of those involved in the crash, many crashes occur due to 

engineering issues. Without fully investigating and reconstructing a crash, the true cause or 

causes of the crash may not be determined.

While the collection of evidence at a crash scene is very important, the crash investigators and 

responders are at risk when they are exposed to vehicular traffic at the incident scene. As 

reported by the Federal Highway Administration’s Traffic Incident Management Program, for 

every minute that the primary incident continues to be a hazard, the chance of being involved in 

a secondary collision increases by 2.8%. Traffic incident management is a vital part of the crash 

investigation process. By utilizing technology effectively for the management of traffic 

incidents and crash investigation, safety is improved and congestion is minimized.

While the safety of responders and motorists is the highest priority in Traffic Incident 

Management and crash investigation, the economic impact of congestion must also be 

considered. According to the 2015 Urban Mobility Scorecard1 published by the Texas A&M

Transportation Institute, travel delays due to traffic congestion caused drivers to waste more than 

three billion gallons of fuel and kept travelers stuck in their cars for nearly seven billion extra 

hours – 42 hours per rush-hour commuter. The result is a total nationwide price tag of $160 

billion, or $960 per commuter. In addition, 18 percent or $28 billion of the delay cost was the 

effect of congestion on truck operations; the cost does not include any value for the goods being 

transported in the trucks. 

The 2015 Urban Mobility Scorecard report predicts urban roadway congestion will continue to 

worsen without more assertive approaches on the project, program, and policy fronts. By 2020, 

with a continued good economy:

• Annual delay per commuter will grow from 42 hours to 47 hours,

• Total delay nationwide will grow from 6.9 billion hours to 8.3 billion hours, 

• Total cost of congestion will jump from $160 billion to $192 billion.

The economic impact of congestion cannot be ignored. The utilization of traffic crash 

reconstruction technology has a significant impact on congestion and the cost to motorists.

The technology available for the investigation and reconstruction of traffic crashes has evolved 

over time. The basic investigative tools are a measuring tape, a rolling measuring device or a 

combination of these tools. The evolution of traffic crash reconstruction technology has 

introduced many new types of equipment to this field, as well as evolving practices and methods. 

 1 2015 Urban Mobility Scorecard, Texas A&M Transportation Institute (August 2015)
Crash Investigation and Reconstruction 2 U.S. Department of Transportation

Technologies and Best Practices Federal Highway Administration

Crash investigation equipment available today is capable of accurately capturing the evidence at 

a crash scene for the purpose of reconstructing crashes. 

The evaluation of technology can be very subjective. To minimize the subjectivity, a panel of 

experts in the field of traffic crash reconstruction was established. The panel, consisting of 

representatives of law enforcement, private traffic crash reconstruction professionals, state 

departments of transportation, and the National Transportation Safety Board (NTSB), was 

consulted to guide the research of the technology. Each technology was rated on Responder 

Safety, Quick Clearance and Court Acceptance using the criteria presented in Table 1. Table 2

summarizes the results of this research.

Table 1. Technology Rating Criteria

Rating Criteria

Responder Safety Very Unsafe Unsafe Safe

Safe, Quick Clearance Extended Clearance Moderate Clearance Time Quick Clearance

Court Acceptance Not Accepted Some Acceptance Accepted
Crash Investigation and Reconstruction 3 U.S. Department of Transportation

Technologies and Best Practices Federal Highway Administration

Table 2. Research Summary

Reconstruction 

Equipment

Roadway 

Clearance

Responder 

Safety

Court 

Acceptance

National 

Unified 

Goal

Ranking

Court 

Acceptance

Ranking

Cost

Ranking

Mechanical 

Measurement Tools 12 1 1

Photogrammetry 7 7 2

Light Detection and 

Ranging (LiDAR) 10 8 3

Electronic Total 

Station 11 2 4

Reflectorless Total 

Station 2 3 5

Global Positioning 

System (GPS) 9 9 6

Semi-Robotic Total 

Station 3 4 7

Robotic Total Station 4 5 8

Imaging Station 6 11 10

Three-dimensional (3-

D) Laser Scanning 8 10 11

Unmanned Aerial 

Devices 1 12 12

Hybrid Total Station 5 6 9

Crash Investigation and Reconstruction 5 U.S. Department of Transportation

Technologies and Best Practices Federal Highway Administration

CHAPTER 1 INTRODUCTION

The Federal Highway Administration’s (FHWA) investigation of practices and technologies that 

affect crash reconstruction supports improved safety of incident responders and the traveling 

public. The successful investigation of these methods guides successful Traffic Incident 

Management (TIM), as identified in the National Unified Goal for TIM (NUG) which can be 

found at http://timnetwork.org/national-unified-goal-nug/. 

Most roadway-related Intelligent Transportation Systems (ITS) mainly address improved 

detection and notification activities as illustrated in Figure 1 which is courtesy of FHWA’s 

Strategic Highway Research Program (SHRP2) National TIM Responder Training Program. 

Roadside detectors and cameras support the identification of traffic disruptions. Cameras add a 

deeper level of validation and understanding, while message signs alert, inform, or guide 

decisions for drivers and those contemplating travel on a roadway. The technology used in crash 

reconstruction, in concert with ITS equipment, supports the timely removal of traffic crash 

obstructions in the response and clearance phases, and maintains the integrity of the crash 

investigation data collected at the scene.

Figure 1. Graph. Traffic Incident Management Event Sequence
Crash Investigation and Reconstruction 6 U.S. Department of Transportation

Technologies and Best Practices Federal Highway Administration

Technologies from other disciplines have been or are being studied and evaluated to support 

crash investigation and TIM activities. Among these are:

• Fire apparatus that are equipped with advanced lighting and incident scene clearance 

tools,

• Ambulances that are equipped with the most recent patient care innovations,

• Towing and recovery vehicles that have computerized systems, 

• Law enforcement professionals that have highly specialized onboard and mobile 

equipment for completing their tasks and contributing to other aspects of TIM.

As agencies move toward reliable reporting of TIM-related performance measures, these 

technologies and the practices that employ them will be vital parts of the maturation of TIM 

programs.

PROGRESSION OF LAW ENFORCEMENT INVESTIGATION 

TECHNOLOGY

There are currently many types of technology used for traffic crash investigation and 

reconstruction. The basic method involves the use of measuring tapes, rolling measuring 

devices, levels and formula calculations to determine the course of events and the cause of a 

crash. This method is currently in use in the majority of law enforcement agencies throughout 

the United States. 

Technological improvements have generally addressed accuracy, speed, or a combination of 

both. However, in some jurisdictions the laws and policies that govern crash investigation have 

not kept pace. When transportation professionals engage law enforcement and other public 

safety professionals, they must recognize that quick clearance starts with responder safety. 

Attention to responder safety priorities can be a sensitive issue in many locations where law 

enforcement professionals feel as though they are being pushed to open roads more quickly and 

without regard for the important task of collecting crash investigation evidence. 

There have been considerable changes in the technology that is available for traffic crash 

reconstruction. Many methods use a platform commonly used in surveying to create a forensic 

map of a crash scene. Other methods use lasers or Global Positioning System (GPS) devices. In 

addition to the forensic maps of the crash scene, many technologies allow for the creation of

crash simulations and three-dimensional (3-D) models. These technologies also capture data 

used to determine the course of events and the cause of a crash.

Much of the technology in use today is widely available and becoming more affordable, while

emerging technology is expensive and not widely available. There is currently no reference 

guide for law enforcement administrators or other traffic crash reconstruction professionals to 

use when planning equipment purchases. The available information is based on the experience 

of individual agencies or manufacturers.

The technologies and best practices identified in this report will assist agencies in determining 

which technologies will best meet their crash investigation and TIM needs. There is no “one size 
Crash Investigation and Reconstruction 7 U.S. Department of Transportation

Technologies and Best Practices Federal Highway Administration

fits all” approach for traffic crash reconstruction. The basic, mechanical measuring process and 

equipment may fit the needs of some, but others may need more advanced, specialized 

capabilities to achieve their goals. The research conducted for this report examined the 

technology in use today, how it can be used to achieve the goals of the NUG, the cost of the 

technology, and its availability for use in traffic crash reconstruction.

The underlying needs for this research are to provide a safer environment for responders, a safer 

environment for motorists, and to minimize the effect that traffic crashes have on traffic flow. 

The manner in which the technology is applied is just as important as the technology itself. The 

most advanced technology available is no more valuable if it is not used in an efficient manner to 

minimize the exposure of personnel to the dangers of traffic in the roadway.

Law enforcement professionals must weigh the need to obtain and record information related to 

crashes versus the danger to investigators, responders and other highway users. Most crashes 

that occur are minor, they are cleared quickly, and do not require in-depth investigation and 

reconstruction. However, in-depth investigation of moderate and major crashes is necessary due 

to the circumstances, severity, or other factors. These crashes take longer to investigate and 

often result in roadway closures. Closing lanes on a highway increases the risk of a second crash 

occurring. In many cases, secondary crashes are more severe than an initial crash. Reducing the 

number of secondary crashes on the nation’s highways is a primary goal of the Federal Highway 

Administration and is an important part of the Towards Zero Initiative. 

A crash reconstructionist has a job that is unique, and any reconstructionist could be faced with a 

scenario such as the following:

1. An incident occurs that requires and gets emergency response.

2. The need for crash reconstruction and investigation is identified and a call is made for a 

trained specialist, who now asks:

• Do I have the technology tools I need and are they in working order?

• Are there special circumstances I need to worry about?

• How has traffic been affected?

• How is traffic affecting the scene?

• Will I encounter delays in ingress to the scene?

• Will the scene be intact or altered by the time I get there?

• Has evidence been preserved?

• What do I need to tell those on-scene to do until I get there?

• Will I need to go anywhere else other than the crash scene?

• Will I need to talk with specific persons not available now?

• How will I communicate with responders on-scene until I arrive?

• When I arrive, what can I do to minimize the effects on traffic while still protecting 

responders and motorists?
Crash Investigation and Reconstruction 8 U.S. Department of Transportation

Technologies and Best Practices Federal Highway Administration

• Is the technology that I have the best for this investigation or do I need to call for 

assistance?

• Can the evidence at the crash scene be marked and the mapping completed at a safer, 

more convenient time?

TRAFFIC CRASH RECONSTRUCTION 101

There is no one type of technology that addresses all the needs for traffic crash reconstruction. 

Each crash or incident involves unique circumstances. In many jurisdictions the cost of training 

and equipment prohibits every officer from being a certified crash reconstructionist. Neither the 

crash reconstructionist nor the needed equipment is involved in the initial incident response.

In many instances the crash reconstructionist (an individual or team) is called to the crash scene

after the initial response. The investigator must rely on first responders to preserve all evidence 

and protect the scene. Anything at the scene of a crash could be evidence, therefore the roadway 

remains closed until the investigators can complete the scene investigation activities. Depending 

upon the response time for the investigator and the necessary equipment, a closure can extend 

from minutes to hours. The availability of the equipment and the proximity to the crash scene 

are vital.

The investigator must record information from the crash scene to complete the reconstruction. 

This data includes, but is not limited to:

• Tire marks,

• Vehicle positions,

• Body positions,

• Marks in the pavement,

• Debris,

• Roadway grade,

• Other environmental evidence.

This information is essential to determining the true cause of a crash and accurate recording is 

essential so that investigation results are uncompromised. The recording of the information is a 

determining factor in the length of time needed for the crash scene investigation. Technology 

can decrease data collection time and improve the accuracy of the data collected. 

Evidence collected at the beginning of the investigation may not be as easily recognized and 

determined due to the nature of modern automobiles. Tire marks and other evidence exist, but 

the life of evidence diminishes if not recorded immediately. Evidence can be marked and 

recorded, roadway markings that are in the travel lanes can be recorded, and the roadway can be 

opened to traffic. Other information for the crash reconstruction, such as the roadway geometry 

can be recorded after the roadway has been reopened to traffic. This approach reduces the 

exposure of investigators to the dangers of traffic and reduces the risk a secondary incident.
Crash Investigation and Reconstruction 9 U.S. Department of Transportation

Technologies and Best Practices Federal Highway Administration

After the investigation at the scene is completed, the recorded information must be processed to 

complete the reconstruction. Modern technology utilizes computer software to complete scale 

diagrams and mathematical calculations to determine speed and other factors, as well as 

determine the cause of the crash. Depending upon the software and the proficiency of the 

investigator in its use, this process can be time consuming. The verification of the results is 

essential even with the use of the computer software. The investigator must be able to defend the 

results of the reconstruction when testifying in court. The technology used in the traffic crash 

reconstruction process assists the investigator with the recording and processing of critical 

information. 

RELATIONSHIP BETWEEN CRASH RECONSTRUCTION AND 

TRAFFIC INCIDENT MANAGEMENT

Effective quick clearance of roadways is a special issue when reconstruction activities are 

required on-scene. Planned and coordinated procedures among all responders creates success 

which is exemplified when the reconstruction teams are familiar with their surroundings, trust 

the responders on-scene to assist, and work with a dual focus on completing the investigation and 

opening the roadway.

Responders and investigators working cooperatively and selecting their work patterns to focus on 

clearance of a lane or lanes progressively help prevent secondary crashes. The coordinated 

efforts include pre-established procedures for evidence preservation protocols that responders 

understand and can easily follow. There are benefits to procedures for responder collection of 

information prior to the arrival of the investigators which are reflected in trimming time from the 

crash investigation and clearance timeline.

While physical evidence is a major part of an investigation, responders can provide context and 

contribute to the efficiency of the investigation associated with appropriate and thorough 

investigative work. Responders can describe changes in weather, effects of passing traffic, and 

give context to the traffic control signage and other directional advice that motorists had if the 

incident is in a work zone or other modified traffic pattern.

Pre-planning and established procedures create a more effective use of TIM. The relationships 

that result from a cooperative TIM environment, from preparedness to response through 

recovery, are the keys to success.

When responders know what investigators need and help provide it, and when investigators 

depend upon that knowledge and experience, the incident scene is safer and the roadway is 

opened more quickly. Lessons learned from those cooperative experiences result in better 

preparedness for the next investigation.

Crash Investigation and Reconstruction 11 U.S. Department of Transportation

Technologies and Best Practices Federal Highway Administration

CHAPTER 2 INPUT FROM EXPERIENCED CRASH 

RECONSTRUCTION PROFESSIONALS

Selection of crash investigation technology at the local levels typically depends on the 

experience of those involved and the cost of what is chosen. An expert panel, diverse in 

experience and geographic location, was convened to assist with the research and report 

development. The collaboration of the Federal Highway Administration (FHWA) and the 

International Association of Chiefs of Police contributed to the panel member selection. The 

panel represents the spectrum of crash reconstruction personnel throughout the United States 

from various law enforcement communities, the private sector and the National Transportation 

Safety Board (NTSB). Panel members are from Arizona, Arkansas, Florida, Illinois, 

Massachusetts, Michigan, Minnesota, Missouri, Nebraska, Oregon, Pennsylvania, Utah, 

Virginia, and Washington State as shown in Figure 2. Names of panel members are listed in 

Table 3 and biographies of each member are included in Appendix A.

Figure 2. Graph. Expert Panel Members' Geographic Distribution

Predicting and determining the future of traffic crash reconstruction requires extensive 

research of the evolution of practices and equipment. Understanding the technology and 

methods evolution that has happened and is happening provides a clearer vision of the 

future.

Most traffic crash investigation in the United States uses traditional measurement tools. The 

tools utilized most commonly are a rolling measurement device or a tape measure. 

Measurements obtained using these mechanical tools are used to create crash scene 

diagrams and to complete mathematical formulas.
Crash Investigation and Reconstruction 12 U.S. Department of Transportation

Technologies and Best Practices Federal Highway Administration

Table 3. Crash Reconstruction Technology and Best Practice Panelists

Name Organization

Tom Simon Arizona Department of Public Safety

Scott Skinner Oregon State Police

Tracy Flynn Pennsylvania State Police

Dave Keltner Illinois State Police

Andy Klane Massachusetts State Police

John Graves Hillsborough County Sheriff’s Office

Mike Anderson Salt Lake County Sheriff’s Office

Victoria Boldt Sarpy County Sheriff’s Office

Keith Jackson Collinsville Illinois Police Department

Bill Johnson Kansas City Missouri Police Department

Brian Reeves Springfield Missouri Police Department

Greg Gravesen St. Paul Minnesota Police Department

Ron Heusser Engineering Accident Analysis

Nate Shigemura Traffic Safety Group, LLC

Matthew S. Jackson Jackson Reconstruction, Inc.

James D. (Dave) Bean National Transportation Safety Board

Angie Kremer, P.E. Michigan Department of Transportation

As traffic crash reconstruction has evolved, other types of technology have become 

available to law enforcement officers. Several law enforcement agencies use equipment

traditionally used by surveyors. Crash investigation equipment that is now readily available 

includes:

• GPS coordinate technology,

• 3-D scanning and imaging equipment,

• Photographing a crash site, 

• Equipment initially developed for speed measurement utilizing lasers.

The evolution of equipment has led to incredible advances, including unmanned aerial systems 

(UAS). Although not currently readily available for public use, research conducted around the 

world is leveraging these advances. The research conducted under this project sought to validate 

significant areas of crash reconstruction including manpower, methodology, and technology. 

These areas of emphasis effectively, quickly and accurately support the use of the results of the 
Crash Investigation and Reconstruction 13 U.S. Department of Transportation

Technologies and Best Practices Federal Highway Administration

investigation in court. Advocates for new approaches who want to convince law enforcement 

agencies to change policies must generally illustrate three things:

• Reliability of the technology,

• Likelihood that court acceptance will be maintained/increased, 

• Increased unobligated time for officers will result.

RESEARCH OF PRACTICES AND TECHNOLOGIES

The project research focused on current traffic crash reconstruction technologies and the existing 

practices employed by traffic crash reconstruction professionals, professional organizations, and 

equipment vendors. A survey gathered information to identify the current traffic crash 

reconstruction technology. 

There are a number of factors to consider when discussing the technology used for traffic crash 

reconstruction. Some of the practices and methods have been used for many years and are still 

very accurate. There are also be practices or technology that are inefficient for crashes on the 

highway since they prolong roadway closures.

Considerations of the research include:

• Availability of equipment and software - There are many software packages available 

and used for reconstruction tasks that lead to the production of a report. The 

compatibility of software is a critical element in selecting technology. The software must 

be capable of interpreting the data and displaying the results. 

• Current usage and acceptance by practitioners and the courts - The technology must 

reliably function as designed and it is essential that it operate consistently in differing 

environments. The reliability depends on the support of the manufacturer and the vendor 

of the equipment. Issues certainly arise in the use of the equipment and the support of the 

manufacturer and vendor is essential for success. Reliability is a key factor for court 

acceptance.

• Ease of use, including training and education requirements - Training requirements 

for proper set-up, use and production of a final result, as well as licensing and/or 

certification of operators are also among the concerns of law enforcement agencies and 

those who are responsible for using the equipment. Specialized training and regular use 

of the equipment is required to sustain proficiency. 
Crash Investigation and Reconstruction 14 U.S. Department of Transportation

Technologies and Best Practices Federal Highway Administration

FUNDING DECISIONS

The decision by law enforcement agencies and private reconstruction firms concerning which 

technology to use is primarily driven by the cost of the equipment and operation. Although 

traffic crash reconstruction is important to all users, the funding that is available decides what 

choices are made.

The purchase of equipment is only the beginning. Software, personnel training, equipment, and 

the maintenance of competencies in the use of the investigation method for court acceptance are 

also vital to the process of traffic crash reconstruction. The expected service life of the 

equipment is an important consideration since a limited service life often results in costs for new 

equipment, procedure changes, and retraining.

The research criteria for this project are equally important to the purchaser and the user of the 

technology. The research examined information concerning the allocation of funding for traffic 

crash reconstruction as many decisions in law enforcement are budget-driven.

Participation in a Traffic Incident Management (TIM) Program as a best practice was an 

important part of the discussion with the Expert Panel and others contacted during the project.

The manner in which a law enforcement agency approaches the investigation and reconstruction 

of a crash is also a factor in determining the best choice of technology. Most of the crashes that 

involve reconstruction are fatal crashes or involve some aspect that may result in litigation. The 

proper recording and recovery of evidence is essential to traffic crash reconstruction. A crash of 

this nature is essentially a crime scene or the basis for some type of civil litigation. The 

application of the technology will determine the effect that the investigation has on responder 

safety, traffic management options, and overall incident management.

One of the aspects of traffic crash reconstruction that is often overlooked is the availability of 

peer support for the technology and the practices that are in place when reconstructing a crash. 

Agencies can share information about their experience and practices with similar equipment and 

methods, further enhancing the capabilities of each organization. A successful program in the 

Midwest involved the purchase of equipment, software and training for law enforcement 

agencies in a large metropolitan area. The program implemented a single software package 

across the agencies to improve the compatibility and consistency of crash investigation 

throughout the area. As a result, there is now a large “team” of reconstruction professionals

throughout that metropolitan area who can assist one another with investigations.

BEST PRACTICES

The project research identified the current best practices and technologies for crash 

investigation and reconstruction. Multiple practices were identified as having great value in 

various situations. The Expert Panel was engaged at various points in the project research 

providing expert insight, input, and review of the results produced. 
Crash Investigation and Reconstruction 15 U.S. Department of Transportation

Technologies and Best Practices Federal Highway Administration

CHAPTER 3 RESEARCH METHODOLOGY

The Expert Panel involved in this project represents the spectrum of crash reconstruction 

professionals throughout the United States. The diversity of the panel is important since, in most 

cases, the policies that govern traffic crash reconstruction are localized and localized policies can 

dictate the technology that is employed. The research team used surveys and interviews of these 

experts to gather information about the equipment and practices employed for crash investigation 

and reconstruction.

SURVEY OVERVIEW

A survey gathered inputs from reconstruction professionals regarding their use of technology and 

how it is utilized to accomplish the National Unified Goal for Traffic Incident Management 

(NUG). The findings revealed various types of technology and practices currently in place 

nationwide. The different practices and technologies currently in use for traffic crash 

reconstruction, as well as those that are emerging were identified and documented. 

The criteria for the analysis included the following:

• Type of technology,

• Availability of technology,

• Acceptance in field of crash investigation and traffic crash reconstruction,

• Current use in field of crash investigation and traffic crash reconstruction,

• Acceptance in court,

• Ease of use,

• Training requirements,

• Training availability,

• License or certification requirements,

• Software compatibility,

• Reliability,

• Vendor/manufacturer support,

• Cost of equipment,

• Cost of upkeep, 

• Service life.

The current practices and technologies were analyzed based on established criteria and were

assessed to identify those that represent the best practices in traffic crash reconstruction. Due to 

the diversity of situations and environments faced by agencies and organizations employing 

crash reconstruction practices and technologies, multiple best practices were identified. 

Surveys, distributed to the members of the Expert Panel and to other professionals in the field of 

traffic crash reconstruction, inquired about the technology they use or they have experience 
Crash Investigation and Reconstruction 16 U.S. Department of Transportation

Technologies and Best Practices Federal Highway Administration

using. Research summary tables for each technology identified were developed supporting 

comparison and providing information about capabilities and benefits. The inputs gathered from 

the survey responses are documented in the tables in Chapter 5 along with information compiled 

through other research sources.

The Expert Panel assisted with the development of the topics in the survey as well as the 

questions. Since the use of the technology to accomplish the goals of the NUG is an essential 

part of this project, the following questions were asked:

Responder Safety How does this technology affect exposure to risk for onscene responders?

Safe, Quick Clearance How does this technology affect clearance times for 

crashes and how does that balance with the collection of 

prosecutorial information?

Prompt, Reliable Communications How can aspects of collected information be used and 

shared to improve incident management activities over 

time?
Crash Investigation and Reconstruction 17 U.S. Department of Transportation

Technologies and Best Practices Federal Highway Administration

CHAPTER 4 RESEARCH RESULTS

The project research activities focused on current traffic crash reconstruction technologies and 

the existing practices utilizing those methods. The research reviewed information available on 

the internet and inputs from traffic crash reconstructionists, professional organizations, and 

equipment vendors who were contacted. The survey discussed in Chapter 3 gathered inputs from 

reconstruction professionals regarding their use of technology and how it is utilized to 

accomplish the National Unified Goal for Traffic Incident Management (NUG). These practices 

range from very simple to technically complex.

The tables in Chapter 5 summarize each technology that is currently in use and those that are 

viewed as useful for the future of traffic crash reconstruction. Provided in Chapter 5 for each 

technology or method is a detailed description followed by a summary sheet which contains the 

research results in the manner described below.

The use of the technology to achieve the goals of the NUG is color-coded in the tables. This 

research data visually depicts the role that the technology and its use play in achieving these 

goals. Each technology was rated on Responder Safety, Quick Clearance and Court Acceptance

using the criteria in Table 4.

Table 4. Technology Rating Criteria

Rating Criteria

Responder Safety Very Unsafe Unsafe Safe

Safe, Quick Clearance Extended Clearance Moderate Clearance Time Quick Clearance

Court Acceptance Not Accepted Some Acceptance Accepted

For the purpose of this project, it was assumed that the technology is being utilized to achieve 

maximum compliance with the NUG. Each technology was rated in the following areas:

• Cost of Ownership – The cost of the technology versus the benefit of its use to the 

collection of prosecutorial information. (1=high cost to low benefit; 5=low cost to high 

benefit),

• Availability – Will the technology be available for all of the crash investigation teams in 

a jurisdiction? (1=no availability; 5=always available),

• Amount of Training Required for Usage – How much training is required to use the 

technology and methods, and attain an original certification on the product? 

(1=burdensome amount of training; 5=little amount of training),

• Retraining to Continue Certification – How often is retraining required to maintain 

certification on the technology? (1=monthly; 5=annual or longer),
Crash Investigation and Reconstruction 18 U.S. Department of Transportation

Technologies and Best Practices Federal Highway Administration

• Setup and Takedown – How much time is required to setup the equipment and take the 

equipment down to store it for future use? (1=long setup/take down; 5=short setup/take 

down),

• Opportunities for Enhancement – Does the technology accommodate future 

enhancement? (1=no future enhancements; 5=high number of enhancements),

• Court Acceptability – Are the technology results accepted in court? (1=not acceptable; 

5=always acceptable).

The scoring matrix provides a range of 1 being the lowest possible score for the category to 5 

being the highest score for the category. For areas of technology that the expert had little to no 

experience, a score of not applicable (N/A) was used.

The totals in the tables were determined by multiplying the number of responses in each category 

by the 1 through 5 rating scale at the top of the table. The values in the tables are intended to 

provide the reader with a comparison of the Expert Panel responses in each rated category. By 

reviewing the information in the tables, the reader will be able to understand the criteria that they 

may need to rate a technology or method considering the acquisition or updating of crash 

reconstruction technology. It is important to note that a high raw score in the tables may not be 

the best choice of technology based upon its compliance with the NUG, its cost, and its 

availability. Those criteria will be detailed further in the report. Not all of the respondents rated 

each category for the different technologies.

Representative survey responses and comments regarding the technology or method in terms of 

Responder Safety, Quick Clearance and Court Acceptance are included to provide additional 

insight and perspective for the reader.

The data, as well as the survey responses and other sources, provide recommendations to readers 

who are contemplating the acquisition or update of crash reconstruction methods. Information is

provided to guide readers based upon the conditions and situations in which the technology will 

be used.

The safety of responders is at the forefront of recommendations. The application method is a 

critical part of the decision-making process to provide a safer environment for responders and 

other highway users, and to minimize any negative impact on traffic conditions.
Crash Investigation and Reconstruction 19 U.S. Department of Transportation

Technologies and Best Practices Federal Highway Administration

CHAPTER 5 TECHNOLOGY OVERVIEW

MECHANICAL MEASUREMENT TOOLS

Mechanical measurement tools typically consist of a measuring tape, a rolling measuring device, 

or a combination of the two. A carpenter’s level is often used to determine the grade(s) of the 

roadways and, when used properly by well-trained investigators, provides incredibly accurate 

results. Additional equipment is needed to create a diagram of the crash scene, including a 

protractor, compass and different types of curves. A summary of the costs of the equipment is 

provided in Table 5.

Table 5. Mechanical Measurement Tools Equipment and Costs

Equipment Cost

Measuring tape $30 to $50

Measuring wheel $70 to $120

Assorted additional equipment $100

The mechanical measuring tools are used to record baseline measurements at a crash scene. The 

technology works well on straight, level roadways, however, accuracy is more difficult to attain 

on curved roadways. Manual recording is required for each measurement and is subject to 

human error.

Mechanical measurement tools are straightforward and the training needed is minimal. 

Investigators can normally create a basic diagram after approximately 4-6 hours of instruction. 

Additional training is required to handle complex crash investigations. Recognized, entry-level

crash investigation courses vary from a few hours to over 40 hours, whereas recognized,

advanced courses vary from 40 hours to 80 hours. 

Well recognized in courts across the country, mechanical measuring tools apply accepted 

mathematical formulas and principles. Mechanical measuring tools have been applied since 

traffic crashes were first investigated. The mathematical formulas for this method of traffic 

crash reconstruction are derived from physics equations. Information collected by more 

advanced types of technology must be capable of verification by use of mechanical measuring 

tools.

While mechanical measuring tools can be very accurate and the results are recognized in court, 

the use of these types of tools increases the exposure of officers and investigators to the dangers 

of traffic and extends the roadway clearance time. In addition, it is difficult to obtain accurate 

measurements at crash scenes involving curved roadways and roadways with significant changes 

in elevation.
Crash Investigation and Reconstruction 20 U.S. Department of Transportation

Technologies and Best Practices Federal Highway Administration

Description: Mechanical Measurement 

Tools

Mechanical measurement tools have long 

been applied to crash investigation. The use 

of cloth tape often required two investigators 

for Trilateration or Cartesian (base line) 

measurement. The roller wheel was 

introduced in 1950.

Average Cost: less than $500

Figure 3. Photo. Mechanical Measurement 

Tool

Source: Michigan State Police

Technology Rating Index – as judged by the experts

Safe, Quick Clearance Responder Safety Court Acceptance

Table 6. How the Experts Rated Mechanical Measurement Tools

CRITERIA 1 2 3 4 5 TOTALS

Cost of Ownership 2 2 15 4 45 68

Availability 1 0 0 0 90 91

Amount of Training Required 0 0 12 4 70 86

Retraining to Continue Certification 0 2 0 4 60 66

Setup and Takedown 2 2 3 16 50 73

Opportunities for Enhancements 15 4 3 0 0 22

Court Acceptability 0 0 21 8 50 79

TOTALS 20 10 54 36 365 485

The following are comments provided by the reviewers about Mechanical Measurement Tools:

• Responder Safety

• Requires personnel close to road and roadway evidence to take measurements.

• Safe Quick Clearance

• Takes a longer period of time to make each measurement, cannot gather as many 

measurements as other methods.

• Takes longer and is less accurate. The value of prosecutorial information depends 

on accuracy needed but is generally lower than other options available.

• Prompt, Reliable Communications

• Information cannot be shared easily unless it is populated into a computer program 

for later use.

• Reliable, but slow and prone to error.
Crash Investigation and Reconstruction 21 U.S. Department of Transportation

Technologies and Best Practices Federal Highway Administration

ELECTRONIC TOTAL STATION

Crash reconstructionists in the United States have utilized the Electronic Total Station since the 

early 1990s. It is comprised of four components: the Theodolite, the Electronic Distance 

Measurement Instrument (EDM), an optical prism, and a data collector. The Electronic Total 

Station utilizes surveying principles to create a map of a crash scene. 

The theodolite is a very precise instrument used to measure horizontal and vertical angles 

between points. The EDM measures the slope distance between points. The Electronic Total 

Station uses reflected light from an optical prism to capture distance and angles from the 

theodolite for each point measured. The geometric data, combined with graphic attributes 

recognized by the software, generates an accurate scale map of the scene. The map is a visual 

depiction of the crash scene and the gathered data can be used in mathematical formulas to 

reconstruct the crash. A summary of the costs of the equipment is provided in Table 8.

Table 7. Electronic Total Station Equipment and Costs

EQUIPMENT COST

Theodolite, Electronic Distance Measurement Instrument (EDM),

Optical Prism, Data Collector, Essential accessories (tripod, prism 

pole(s), tape measure).

$8,000 to $10,000 

(varies widely)

There are a number of manufacturers of Electronic Total Stations. Although they may vary in 

the accessories that are available, they function much the same, measuring angles and slope 

distances. There are a number of data collectors available for use with the Electronic Total 

Station, some of which are weather resistant for use in inclement conditions. Some Electronic 

Total Stations are not well suited for use in inclement weather which could skew the data 

collection results as well as damage the equipment. 

The use of an Electronic Total Station is more complex than the mechanical measuring process;

therefore the training is much more extensive. The recommendation for the basic training 

necessary is a minimum of 40 hours and does not include field projects that should be completed 

following the basic course. In addition to the basic training and field projects, operators must use 

the equipment frequently to maintain proficiency. 

Crash investigation techniques involving the use of an Electronic Total Station are accepted in 

courts across the United States. The principles for creating a map of a crash scene are the same

as those used in surveying applications. The data consists of angle and distance measurements 

that are calculated and used by software to document the crash scene. 

Although the data collected using an Electronic Total Station is very precise, its use increases the 

exposure of officers and investigators to the dangers of traffic. The use of the Electronic Total 

Station requires that the measurements be obtained with the use of an optical prism located 

directly over the evidence to document or map. This process can be slow depending upon the 

complexity of the crash scene and the proficiency of those operating the equipment. In addition 

to the increased exposure to traffic, the roadway clearance time is lengthened. The roadway or 

traffic lanes must remain closed while the measurements are collected.
Crash Investigation and Reconstruction 22 U.S. Department of Transportation

Technologies and Best Practices Federal Highway Administration

Description: Electronic Total Station

Electronic Total Stations produced from 1990 to 

about 2000 are controlled by an internal 

microprocessor, allowing performance of a 

number of different measuring tasks. These tasks 

include staking out points, polar coordinate 

measurements, making calculations, and 

communicating data to a field data collector. 

This unit is infrared only and not capable of 

reflectorless measuring. 

Average Cost: $9,400

Figure 4. Photo. Electronic Total Station

Source: Kansas City Police Department and 

KC Scout

Technology Rating Index – as judged by the experts

Safe, Quick Clearance Responder Safety Court Acceptance

Table 8. How the Experts Rated Electronic Total Station

CRITERIA 1 2 3 4 5 TOTALS

Cost of Ownership 0 0 21 12 10 43

Availability 0 0 0 20 35 55

Amount of Training Required 0 2 24 12 0 38

Retraining to Continue Certification 0 4 15 0 20 39

Setup and Takedown 1 4 15 12 5 37

Opportunities for Enhancements 1 12 6 4 10 33

Court Acceptability 0 0 0 4 55 59

TOTALS 2 22 81 64 135 304

The following are comments provided by the reviewers about Electronic Total Station:

• Responder Safety

• Reduces exposure to traffic when compared to manual measurement means. Still 

requires some exposure to traffic by prism pole operator.

• Reduces risk to investigators, reduces on-scene crash investigation time.

• Safe Quick Clearance

• Set up is heavily dependent on the individual operator's expertise in using it. For 

those properly trained, set up is not time-consuming and subsequent measurements 

can be taken much quicker (and with more precision and accuracy) than the roller 

wheel or tape methods.

• Prompt, Reliable Communications

• Very easy to share data.

• Data format easily shared between parties, somewhat dependent on the knowledge of 

the individual storing the data. An individual not properly trained could produce a 

nearly indecipherable data file.
Crash Investigation and Reconstruction 23 U.S. Department of Transportation

Technologies and Best Practices Federal Highway Administration

REFLECTORLESS ELECTRONIC TOTAL STATION

The Reflectorless Electronic Total Station followed as a variation of the Electronic Total Station, 

and has been in use for reconstruction in the United States since approximately 2001. The 

Electronic Total Station is comprised four components which include the Theodolite, the 

Electronic Distance Measurement Instrument (EDM), an optical prism, and a data collector. 

Similar to the Electronic Total Station, the Reflectorless version utilizes the principles of 

surveying to create a map of a crash scene. The Reflectorless version adds the functionality of 

reflectorless measurements to about 350 meters, or 1150 feet. These distances are to an industry 

standard grey card. When measuring to a roadway from ground level, a user should expect 

maximum measurements to about 400 feet.

The theodolite is a very precise instrument used to measure horizontal and vertical angles 

between points. The EDM measures the slope distance between points. The Electronic Total 

Station uses reflected light from an optical prism to capture distance and angles from the 

theodolite for each point measured. The geometric data, combined with graphic attributes 

recognized by the software, generates an accurate scale map of the scene. The map is a visual 

depiction of the crash scene and the gathered data can be used in mathematical formulas to 

reconstruct the crash. A summary of the costs of the equipment is provided in Table 11.

Table 9. Reflectorless Electronic Total Station Equipment and Costs

EQUIPMENT COST

Theodolite, Electronic Distance Measurement Instrument (EDM), Optical 

Prism, Data Collector, and essential accessories (tripod, prism pole(s), tape 

measure).

$7,000 to 

$8,000

Collector and Evidence Recorder. $2,400

Forensic Computer Aided Diagramming (CAD) Software. $1,000

The Reflectorless Total Station added the ability to record measurements with the EDM without 

the use of an optical prism. The station aims at the point of interest directly, eliminating the need 

to hold the prism pole over the point. The EDM utilizes a laser rather than the infrared signal to 

measure the slope distance. These measurements are limited in range. As with the Electronic 

Total Station, at each point the precision aiming must be performed before the measurement is 

taken. 

Since the use of a Reflectorless Electronic Total Station is more complex than the mechanical 

measuring process, the training is much more detailed. The recommendation for the basic 

training necessary is a minimum of 40 hours and does not include field projects that should be 

completed following the basic course. In addition to the basic training and field projects, 

operators must use the equipment frequently to maintain their proficiency and maintain court 

acceptance.

Using a Reflectorless Electronic Total Station, the technician can minimize personal exposure to 

traffic by carefully selecting the instrument location and recording measurements in the 

reflectorless mode. When the reflectorless mode is selected, the mapping time lengthens as 
Crash Investigation and Reconstruction 24 U.S. Department of Transportation

Technologies and Best Practices Federal Highway Administration

measurements are timed to be recorded between vehicles while the roadway is open to traffic. 

However, since these measurements are being collected while the roadway is open to traffic, the 

effect on traffic flow is minimal. 
Crash Investigation and Reconstruction 25 U.S. Department of Transportation

Technologies and Best Practices Federal Highway Administration

Description: Reflectorless Total Station

In addition to the features from previous total stations, the 

Reflectorless Total Station allows for measurements to 

objects or points without placing an optical prism at those 

points. The process includes: pointing the instrument towards 

the relevant evidence point, aiming the crosshair at the object 

and pressing the data collector button to collect the shot. The 

reflectorless function of the EDM portion of the instrument 

permits distances to be measured well beyond normal crash 

scene distances. These instruments when first introduced 

allowed reflectorless measurements up to 350 meters or 1150

feet.

Average Cost: $18,200

Figure 5. Photo. Reflectorless 

Total Station 

Source: KC Scout

Technology Rating Index – as judged by the experts

Safe, Quick Clearance Responder Safety Court Acceptance

Table 10. How the Experts Rated Reflectorless Total Station

CRITERIA 1 2 3 4 5 TOTALS

Cost of Ownership 0 2 18 20 20 60

Availability 0 2 3 24 35 64

Amount of Training Required 0 0 36 8 10 54

Retraining to Continue Certification 0 4 18 4 25 51

Setup and Takedown 0 4 24 20 5 53

Opportunities for Enhancements 0 12 9 16 10 47

Court Acceptability 0 0 0 4 75 79

TOTALS 24 108 96 180 408

The following are comments provided by the reviewers about Reflectorless Total Station:

• Responder Safety

• Optimal, fairly available measurement device. In many cases, enables 

measurements to be taken some distance from the roadway and out of traffic.

• Greatly lowers exposure risk since no officer need be in the roadway.

• Reduces on-scene crash investigation time.

• Safe Quick Clearance

• Allows relatively quick scene clearances, compared to tape measures, etc. Captures 

scene detail required for diagrams and reconstruction analysis.

• Reduces time necessary to set up and take down, as well as reduced time to measure, 

all reducing time to return to a normal traffic pattern.

• Prompt, Reliable Communications

• Data is easy to share.

• Information can be shared with anyone who has a compatible program that will 

communicate with the total station.
Crash Investigation and Reconstruction 26 U.S. Department of Transportation

Technologies and Best Practices Federal Highway Administration

SEMI-ROBOTIC TOTAL STATION

The Semi-Robotic Total Station followed as a variation of the Electronic Total Station and has 

been in use for traffic crash reconstruction in the United States since the early 2000’s. The semirobotic total station is comprised of four components. These components are the Theodolite, the 

Electronic Distance Measurement Instrument (EDM), an optical prism, and a data collector. A 

summary of the costs of the equipment is provided in Table 14.

Table 11. Semi-Robotic Equipment and Costs

EQUIPMENT COST

Theodolite, Electronic Distance Measurement Instrument (EDM), Optical 

Prism, Data Collector, and essential accessories (tripod, prism pole(s), tape 

measure).

$14,200

Collector and Evidence Recorder. $2,400

Forensic Computer Aided Diagramming (CAD) Software. $1,000

The Electronic Total Station and the Reflectorless variant utilize the principles of surveying to 

create a map of a crash scene. The Semi-Robotic variant eliminates the need to mechanically 

aim the EDM at the prism. A tracking laser maintains aim automatically and updates distance 

measurements. The Semi-Robotic Total Station increases the ability to measure in the 

reflectorless mode to 500 meters or approximately 1640 feet. When measuring to a roadway 

from ground level, a user should expect maximum measurements to about 700 feet. The 

measurement time is reduced since the instrument is constantly measuring.

The theodolite is a very precise instrument used to measure horizontal and vertical angles 

between points. The EDM measures the slope distance between points. The Semi-Robotic Total 

Station uses a laser reflected from an optical prism to capture these angles and distances. The

collected data provides attributes which are recognized by the software. The data is input to 

diagramming software designed to create a scale map of the scene. The map is a visual depiction 

of the crash scene and the gathered data can be used in mathematical formulas to reconstruct the 

crash. 

The Semi-Robotic Total Station includes the ability to record measurements with the EDM 

without the use of an optical prism by an added function of auto-tracking the prism. The station 

is motorized horizontally and vertically. As the laser tracks the prism’s movement about the 

scene, the need to precisely focus and aim the station is eliminated. There are occasions when 

obstacles block the laser and a loss of auto-tracking occurs. The station operator may reestablish tracking or a remote aiming process may be performed to point the station toward the 

prism to reinitialize auto-tracking. The communication range between the collector and station is 

about 350 meters or 1150 feet.

As the use of a Semi-Robotic Total Station is more complex than the mechanical measuring 

process, the training is much more involved. The recommendation for the basic training 

necessary is a minimum of 40 hours and does not include field projects that should be completed 
Crash Investigation and Reconstruction 27 U.S. Department of Transportation

Technologies and Best Practices Federal Highway Administration

following the basic course. In addition to the basic training and field projects, operators must use 

the equipment frequently to maintain their proficiency and maintain court acceptance.

With the use of a Semi-Robotic Total Station, the technician can minimize personal exposure to 

traffic by carefully selecting the instrument location and recording measurements in the 

reflectorless mode. When this option is selected, the mapping time may be lengthened as 

measurements are timed to be recorded between vehicles while the roadway is open to traffic. 

However, since these measurements are collected while the roadway is open to traffic, the effect 

on traffic flow is minimized.
Crash Investigation and Reconstruction 28 U.S. Department of Transportation

Technologies and Best Practices Federal Highway Administration

Description: Semi-Robotic Total Station

Unassisted operation for measuring and 

recording of data. The Semi-Robotic Total 

Station seeks out an Active Remote 

Measuring Target (RMT), locks onto it, and 

follows movement between points. No fine 

adjustments or focusing are needed and 

there are no issues working in the dark. In 

most cases, it is possible to stake out and 

gather survey data as fast as the system can 

move.

Average Cost: $20,900

Figure 6. Photo. Semi-Robotic Total Station

Source: Kansas Highway Patrol and CSI Mapping

Technology Rating Index – as judged by the experts

Safe, Quick Clearance Responder Safety Court Acceptance

Table 12. How the Experts Rated Semi-Robotic Total Station

CRITERIA 1 2 3 4 5 TOTALS

Cost of Ownership 0 6 9 8 0 23

Availability 4 0 9 4 0 17

Amount of Training Required 0 2 18 0 0 20

Retraining to Continue Certification 0 2 9 0 10 21

Setup and Takedown 0 6 3 8 0 17

Opportunities for Enhancements 0 4 9 0 5 18

Court Acceptability 0 0 0 4 30 34

TOTALS 4 20 57 24 45 150

The following are comments provided by the reviewers about Semi-Robotic Total Station:

• Responder Safety

• Lower risk and exposure to traffic than mechanical and electronic total station. User 

can set up in a safe area to avoid traffic.

• Reduces risk to investigators, reduces on-scene crash investigation time.

• Safe Quick Clearance

• Reduces the quick clearance time of other total station instruments by removing the 

need to find and focus on areas of interest through scope.

• Set up heavily dependent on the individual operator's expertise in using it. For those 

properly trained, set up is not time-consuming and subsequent measurements can be 

taken much quicker (and with more precision and accuracy) than the roller wheel or 

tape methods.

• Prompt, Reliable Communications

• Data is easy to share.

• Information can be shared with anyone who has a compatible program that will 

communicate with the total station.
Crash Investigation and Reconstruction 29 U.S. Department of Transportation 

Technologies and Best Practices Federal Highway Administration

ROBOTIC TOTAL STATION

The Robotic Total Station followed as a variant of the Electronic Total Station and has been in 

use for traffic crash reconstruction in the United States since the mid 2000’s. The Robotic Total 

Station is comprised of five components: Motorized Theodolite, Electronic Distance 

Measurement Instrument, Optical Prism, Data Collector, and a Repeater. Like the other 

variations of the Electronic Total Station, the Robotic variant uses the principles of surveying to 

create a map of a crash scene. It eliminates the need to mechanically aim the EDM at the prism. 

The fully Robotic Total Station provides an added function of auto-tracking the prism via a 

remote controller. The controller functions to re-establish tracking of the prism more efficiently. 

A search command can be sent from the remote controller to the command station to turn to the 

prism, eliminating the need to manually aim the station at the prism and return to the prism lock 

status.

A tracking laser is used to maintain aim automatically and updates distance measurements. The 

Robotic Total Station increases the ability to measure in the reflectorless mode to 100 meters or 

approximately 3280 feet. When measuring to a roadway from ground level, a user should expect 

maximum measurements to about 1200 feet, which is sufficient to cover a 1⁄4 mile crash site. The 

measurement time is reduced since the instrument is constantly measuring and updating the 

collector.

The station is motorized horizontally and vertically. As the laser tracks the prism’s movement 

about the scene, the need to precisely focus and aim the station is eliminated. The addition of the 

repeater provides the option of one person operation at incident scenes. The data collector 

connects to the repeater which then connects to the unit via a long range Bluetooth. Should 

connection be lost, the repeater provides a method to reconnect the devices. 

The theodolite is a very precise instrument used to measure horizontal and vertical angles 

between points. The EDM measures the slope distance between points. The Robotic Total 

Station utilizes an infrared light laser that is reflected from an optical prism to capture distances. 

The collected data is given attributes which are recognized by the software. The data is 

transferred into diagramming software designed to create a scale map of the scene. The map is a 

visual depiction of the crash scene and the gathered data can be used in mathematical formulas to 

reconstruct the crash. A summary of the costs of the equipment is provided in Table 17. 

Table 13. Robotic Total Station Equipment and Costs 

EQUIPMENT COST

Theodolite, Electronic Distance Measurement Instrument (EDM), Optical 

Prism, Data Collector, and essential accessories (tripod, prism pole(s), tape

measure).

$18,300

Collector and Evidence Recorder. $2,400

Forensic Computer Aided Diagramming (CAD) Software. $1,000

As with the other variations of the Electronic Total Station, the Robotic variant is more complex, 

and the training is much more involved. The basic training necessary is recommended to be a 
Crash Investigation and Reconstruction 30 U.S. Department of Transportation

Technologies and Best Practices Federal Highway Administration

minimum of 40 hours and does not include field projects that should be completed following the 

basic course. In addition to the basic training and field projects, operators must use the 

equipment frequently to maintain their proficiency. 

The technician can minimize exposure of personnel to the dangers of traffic by carefully 

selecting the instrument location. When the Robotic Total Station arrives at the incident scene in 

a timely manner, the mapping of the scene can usually be completed by the time vehicle removal 

is complete. In cases where points of evidence remain to be measured, the reflectorless 

configuration is available to complete the work. When the reflectorless option is selected, the 

mapping time may be lengthened as measurements are timed to be recorded between passing 

vehicles while the roadway is open to traffic. However, since these measurements at being taken 

while the roadway is open to traffic, the effect on traffic flow is minimized.
Crash Investigation and Reconstruction 31 U.S. Department of Transportation

Technologies and Best Practices Federal Highway Administration

Description: Robotic Total Station

Introduced in the 2000’s, Robotic Total stations operate 

unassisted and allow the operator to control the instrument 

from a data collector via remote control. The Auto-tracking

feature (an upgrade from auto pointing) allows measurement 

of distance by a modulated infrared carrier signal, generated 

by a small, solid-state emitter aligned with the instrument’s 

optical path and reflected by a 360 degree prism. The 

maximum reflectorless range of these instruments is about 

500 meters or 1,640 feet.

Average Cost: $26,200

Figure 7. Photo. Robotic Total 

Station 

Source: Missouri State Highway 

Patrol

Technology Rating Index – as judged by the experts

Safe, Quick Clearance Responder Safety Court Acceptance

Table 14. How the Experts Rated Robotic Total Station

CRITERIA 1 2 3 4 5 TOTALS

Cost of Ownership 1 4 6 12 5 28

Availability 3 2 6 12 0 23

Amount of Training Required 0 0 21 4 0 25

Retraining to Continue Certification 0 2 9 0 15 26

Setup and Takedown 0 4 15 4 0 23

Opportunities for Enhancements 0 4 9 8 0 21

Court Acceptability 0 0 0 0 40 40

TOTALS 4 16 66 40 60 126

The following are comments provided by the reviewers about Robotic Total Station:

• Responder Safety

• Cuts exposure time greatly. Less manpower required on-scene.

• Reduces investigators risk and on-scene crash investigation time.

• Safe Quick Clearance

• Allows very quick measurements of all scene data. Scenes are cleared much quicker 

than traditional methods. Captures much more scene detail because of ease and 

speed of use.

• Reduced time on-scene and processing from older models.

• Prompt, Reliable Communications

• Mostly flawless data collection and sharing. The data formats are usually 

compatible with most of the diagramming programs used in the industry.

• Information reviewed and analyzed for building safer roads and traffic patterns as 

well as adjusting law enforcement activities in those areas.
Crash Investigation and Reconstruction 32 U.S. Department of Transportation

Technologies and Best Practices Federal Highway Administration

TOTAL STATION HYBRID

The Total Station Hybrid is a recent variant of the Electronic Total Station. The use of this 

variant is increasing in the field and is currently used by a number of agencies and organizations 

in the United States, including the National Transportation Safety Board (NTSB).

The Total Station Hybrid is comprised of seven components consisting of the Motorized 

Theodolite, Electronic Distance Measurement Instrument, Optical Prism, Data Collector, a 

Repeater, a Global Positioning System (GPS) Antenna, and a Data Pack. The Total Station 

Hybrid has all of the functionality of the Robotic Total Station and adds Real Time Kinematic 

(RTK) GPS. A summary of the costs of the equipment is provided in Table 20.

Table 15. Total Station Hybrid Equipment and Costs

EQUIPMENT COST

Theodolite, Electronic Distance Measurement Instrument (EDM), Optical 

Prism, Data Collector, and essential accessories (tripod, prism pole(s), tape 

measure).

$34,000

Collector and Evidence Recorder. $2,400

Forensic Computer Aided Diagramming (CAD) Software. $1,000

The Total Station Hybrid method supports one-person operation and beyond line of sight 

measurements. Up to this point, the Electronic Total Stations discussed have been capable of 

line of sight measurements only. For beyond line of sight measurement, the Total Station Hybrid 

is transitioned to GPS measurement. The repeater and the GPS functions may not be used 

simultaneously.

The true Hybrid mode is a blend between the Robotic Total Station and GPS. The Total Station 

Hybrid uses polar coordinate measuring on all three axes assisted by RTK GPS.

The GPS technology in this application operates more accurately than GPS, Assisted GPS 

(AGPS), Differential GPS (DGPS) and Wide Area Augmentation System (WAAS). Surveygrade measurement requires some repeatability in measurement. A minimum of three 

measurements are averaged to meet the general recommendation for reliability. Elevation data 

should always be recorded optically when the measurement is critical to an analysis. The robotic 

functionality eliminates the need to mechanically aim the EDM at the prism. The Total Station 

Hybrid provides the function of auto-tracking the prism via a remote controller. The controller 

functions to reestablish tracking of the prism more efficiently. A search command from the 

remote controller to the station turns the station to the prism which eliminates the need to 

manually aim the station at the prism and return to a prism lock status.

Similar to the Robotic Total Station, a tracking laser maintains aim automatically and updates 

distance measurements. The Total Station Hybrid has the ability to measure in the reflectorless 

mode to 1000 meters or approximately 3280 feet. These distances are to an industry standard 

grey card. When measuring to a roadway from ground level, a user should expect maximum 
Crash Investigation and Reconstruction 33 U.S. Department of Transportation

Technologies and Best Practices Federal Highway Administration

measurements to about 1200 feet. The measurement time is reduced since the instrument is 

constantly measuring.

The Total Station Hybrid is motorized to rotate horizontally and vertically. As the laser tracks 

the prism movement about the scene, the need to precisely focus and aim the station is 

eliminated. The added functionality of the RTK GPS provides the ability to measure evidence 

points beyond line of sight of the station. This method requires a wireless connection to a base 

station. In remote locations, where a public base station is not available, a private connection 

may be available for purchase or remote base stations may be erected by the mapping technician.

The theodolite is a very precise instrument used to measure horizontal and vertical angles 

between points. The EDM measures the slope distance between points. The Total Station 

Hybrid uses an infrared light reflected from an optical prism, or point of evidence when used in 

the reflectorless mode, to capture distances. For line of sight measurements, the data provides 

attributes which are recognized by the software. When the GPS function is used, the Total 

Station Hybrid records the polar coordinates of the evidence points. The data is input to software 

designed for creating a scale map. The map is a visual depiction of the crash scene and the 

gathered data can be used in mathematical formulas used to reconstruct the crash.

As with other variants of the Electronic Total Station, the Total Station Hybrid is more complex 

and the training is much more involved. The basic training that is necessary is a minimum of 40 

hours and does not include field projects that should be completed following the basic course. In 

addition to the basic training and field projects, operators must use the equipment frequently to 

maintain their proficiency and court acceptance.

Crash investigation techniques involving the use of an Electronic Total Station are accepted in 

courts across the United States. The use of GPS technology is also recognized as accurate. The 

combination of the Electronic Total Station and GPS technology has been utilized in the survey 

industry for many years. The principles for creating a map of a crash scene are the same as 

applied in surveying. The data consists of angle and distance measurements and the calculated 

polar coordinates used by software to document the crash scene. It is essential that the operator 

of the equipment be properly trained and proficient in the use of the equipment for courts to 

recognize its results.

The technician can minimize personal exposure to traffic by carefully selecting the instrument 

location and recording measurements in the reflectorless mode. When the Total Station Hybrid 

arrives at the incident scene in a timely manner, mapping can be accomplished by the time 

vehicle removal is complete. In cases where points remain to be measured, the reflectorless 

configuration is available to complete the work. The added functionality of the RTK GPS 

provides the ability to measure evidence points beyond line of sight of the station. This method 

requires a wireless connection to a base station. In remote locations where a public base station 

is not available, a private connection may be available for purchase or remote base stations may 

be erected by the mapping technician. 
Crash Investigation and Reconstruction 34 U.S. Department of Transportation

Technologies and Best Practices Federal Highway Administration

Description: Total Station Hybrid

In addition to the features provided by robotic sets, the Total 

Station Hybrid switches from either auto-tracking the prism 

or control by the remote control prism unit to RTK GPS 

measurements when the prism is out of view of the 

instrument. Position data is determined by receiving signals 

from GPS satellites. GPS systems in application could have 

errors on the order of millimeters to centimeters. 

Reflectorless range increases to 1000 meters.

Average Cost: $35,800

Figure 8. Photo. Total Station 

Hybrid 

Source: Sokkia Corporation

Technology Rating Index – as judged by the experts

Safe, Quick Clearance Responder Safety Court Acceptance

Table 16. How the Experts Rated Total Station Hybrid

CRITERIA 1 2 3 4 5 TOTALS

Cost of Ownership 2 2 0 4 10 18

Availability 3 0 3 0 10 16

Amount of Training Required 0 2 6 8 0 16

Retraining to Continue Certification 0 2 6 4 5 17

Setup and Takedown 0 4 3 8 0 15

Opportunities for Enhancements 0 0 3 12 0 15

Court Acceptability 0 0 0 0 25 25

TOTALS 5 10 21 36 50 122

The following are comments provided by the reviewers about Total Station Hybrid:

• Responder Safety

• Requires target to be over evidence, meaning in scenes that are not closed to traffic, 

individual must be in the road.

• Reduces risk to investigators, reduces on-scene crash investigation time.

• Safe Quick Clearance

• Reduces quick clearance time as opposed to other total station instruments by cutting 

out the need to find and focus on areas of interest through scope.

• Enhances TIM quick clearance.

• Prompt, Reliable Communications

• Mostly flawless data collection and sharing. The data formats are usually 

compatible with most of the diagramming programs used in the industry.

• Information reviewed and analyzed for building safer roads and traffic patterns as 

well as adjusting law enforcement activities in those areas.
Crash Investigation and Reconstruction 35 U.S. Department of Transportation

Technologies and Best Practices Federal Highway Administration

CLOSE-RANGE PHOTOGRAMMETRY

Modern Close-Range Photogrammetry systems, (herein referred to as “photogrammetry”) 

consists of a consumer grade digital single-lens reflex (SLR) camera with a wide angle lens. 

Photogrammetry, utilizing software, has been used for traffic crash reconstruction in the United 

States since approximately 1992. The camera is calibrated and used with photogrammetric 

markers for scene measurements. Photogrammetry is the use of photographs or digital images, 

to obtain measurements for the purpose of constructing two-dimensional (2-D) and threedimensional (3-D) diagrams of crash or crime scenes. A summary of the costs of the equipment 

is provided in Table 23.

Table 17. Photogrammetry Equipment and Costs

EQUIPMENT COST

Digital SLR Camera and lens. $1,000

Photogrammetric markers (40). $500

Software Basic version. $1,000

Software Professional version. $2,595

Photographing a crash scene uses a camera calibrated for photogrammetry with specific camera 

and lens settings to “measure” feature points of interest. In Photogrammetry, 2-D measurements 

can be made in a plane with one photograph through a process called orthorectification.

In 3-D, multiple photographs are used in a process called convergent triangulation. Strong 

perspective overlap of featured points of interest is required to successfully obtain 3-D

measurements from the digital images.

On-scene, the investigator acquires sufficient photographs of the objects of interest. Each feature 

point of interest needs observation in at least 3 images from different perspective viewpoints in 

order to support accurate measurements.

Ideally, points of evidence are captured in at least three overlapping photographs. The 

photographs are imported into a Photogrammetry software program where the operator 

references 2-D images and the 2-D references are triangulated into 3-D object points through a 

process called bundle triangulation. The photogrammetry 3-D dataset of points, lines and 

polylines can then be exported as a Drawing Interchange Format (DXF) file and input to most 

Computer Aided Diagramming (CAD) programs to draw a diagram of the scene to scale.

The training that is necessary to become proficient in the use of Photogrammetry is not as 

extensive as the training necessary to become proficient with any of the variations of the 

Electronic Total Station. A recommended basic amount of training is three days. As with other 

types of technology, the investigator must use the photogrammetry system to maintain 

proficiency and court acceptance.

While the photographs may be taken by someone who is not familiar with photogrammetry or 

evidence identification, the use of the photogrammetry software to process the data requires the 
Crash Investigation and Reconstruction 36 U.S. Department of Transportation

Technologies and Best Practices Federal Highway Administration

investigator be familiar with the process and be proficient. Crash investigation techniques 

involving photogrammetry have been accepted in courts in the United States.

The use of Photogrammetry can aid in the quick clearance of traffic crashes. The scene of more 

serious crashes requires the use of photographs to record the crash scene. Photogrammetry 

combines the processes of photography and measurement. It can be completed by one person

which reduces the manpower needs at the scene of crashes. Since digital cameras are more 

readily available and accessible than other types of technology, there is less time involved in 

waiting for the arrival of reconstruction equipment. 

The use of photogrammetry is limited by weather conditions, much like other types methods in 

use today. The investigator must be able to see the evidence measured. While the at-scene time 

may be reduced by the use of Photogrammetry, the processing of the data for the purposes of 

reconstruction may involve more time on the part of the investigator in the post-processing of the 

photographs on a computer. The time savings using photogrammetry is realized at-scene for 

quick clearance objectives. The post-processing of the photographs is generally about the same 

time as the overall combined at-scene and post-processing work required using a total station.
Crash Investigation and Reconstruction 37 U.S. Department of Transportation

Technologies and Best Practices Federal Highway Administration

Description: Photogrammetry

Photogrammetry is the science of making 

measurements from photographs, especially 

for recovering the exact positions of surface 

points. Photogrammetry systems use a 

calibrated lens mounted on SLR cameras. 

Employed to reduce at-scene investigation 

time, post-processing is required to produce a 

crash diagram.

Average Cost: $1,000 to 4,000 with templates 

and software Figure 9. Photo. Photogrammetry

Source: Timothy Robbins of M-CRASH Group, 

LLC.

Technology Rating Index – as judged by the experts

Safe, Quick Clearance Responder Safety Court Acceptance

Table 18. How the Experts Rated Photogrammetry

CRITERIA 1 2 3 4 5 TOTALS

Cost of Ownership 0 0 12 8 20 40

Availability 3 4 6 8 10 31

Amount of Training Required 1 4 12 12 5 34

Retraining to Continue Certification 0 2 3 16 10 31

Setup and Takedown 0 2 3 12 30 47

Opportunities for Enhancements 0 2 0 12 35 49

Court Acceptability 0 0 9 8 25 42

TOTALS 4 14 45 76 135 274

The following are comments provided by the reviewers about Photogrammetry:

• Responder Safety

• Increases safety since a scene can be quickly mapped.

• Reduces risk to investigators, reduces on-scene crash investigation time.

• Requires placement of targets in the road and extra time to photograph the scene 

properly.

• Safe Quick Clearance

• One of the fastest methods to create an accurate diagram thus can greatly accelerate 

clearance times.

• Very good, two steps done (measurements & photographs) in one step 

(photographs).

• Prompt, Reliable Communications

• Output easily imported into diagramming software packages.

• Properly taken photographs allow other information to be extracted at a later date.
Crash Investigation and Reconstruction 38 U.S. Department of Transportation

Technologies and Best Practices Federal Highway Administration

THREE-DIMENSIONAL LASER SCANNING

Three-dimensional (3-D) Laser Scanning has been adopted in many areas of the country as a tool 

for traffic crash reconstruction, and has increased significantly in the past 10 years. The 3-D 

Laser Scanner consists of a phase shift, a time-of-flight laser measuring device, or both. A 

summary of the costs of the equipment is provided in Table 26. The laser scanner is placed on a 

tripod and, while rotating horizontally, spins a mirror vertically to make measurements by 

indiscriminately distributing a laser beam. As many as a million measurements per second can 

be recorded by certain models. However, similar to the total station reflectorless mode, the laser 

has a limited range. When the angle of incident is low between the laser head and roadway, the 

effective measurement range is reduced.

Table 19. Three-dimensional Laser Scanning Equipment and Costs

EQUIPMENT COST

Three-dimensional (3-D) Laser Scanning. $60,000 to $200,000

Annual calibration. $5,000

The 3-D Laser Scanners capture what is in the line of sight of the scanner. The 3-D scanners 

allow for operation by one person which reduces the number of personnel exposed to the dangers 

of traffic. The time necessary to complete a scan is dependent upon the density of the scan. 

Higher density scans require longer scan times.

The end product is not a typical line drawing. A point cloud is generated on which analysis must 

be performed. As an example, an analysis is necessary to determine where a curb transitions into 

the roadway surface. There is a large amount of data that is recorded, and the data may be used 

for many purposes. 

The 3-D Laser Scanners in use today for traffic crash reconstruction are also equipped with a 

high-definition (HD) digital camera to accurately document the crash scene. The 3-D Laser 

Scanners do not require a target and are much more automated than previous versions. The 

processing time for the data is significantly less than in the past and the data can easily be 

managed by a computer. The 3-D Laser Scanner produces a photo-like product that can be 

imported into computer aided diagramming (CAD) software. In addition, the data allows the 

investigator to view the scene from different points of view in the scan.

Due to the complexity of the 3-D scanner, specialized training is necessary to become proficient 

in its use. Training is available from the equipment manufacturers and from training providers. 

The recommendation is a minimum of 24 hours of training in the use of the software to process 

the data. This training may not provide specific information in the use of the 3-D Laser Scanner 

to reconstruct traffic crashes. 

Law enforcement investigators recommend that a minimum of 40 hours of training be completed 

in the use of the software and the equipment including the basic training and application in traffic 

crash reconstruction. The use of the software to process the data requires that the investigator be 

familiar with the process and be proficient.
Crash Investigation and Reconstruction 39 U.S. Department of Transportation

Technologies and Best Practices Federal Highway Administration

Crash investigation reports involving the use of 3-D Laser Scanning have been accepted in courts 

in the United States. While the science involving 3-D Laser Scanning has been accepted, it is 

essential that the operator be properly trained and proficient in the use of the equipment for 

courts to recognize the results it produces.

The use of 3-D Laser Scanning can be beneficial in quickly clearing traffic crashes. If the 

scanner is readily available, the scan can be completed in a matter of minutes. As indicated 

above, the higher the density of the scan, the longer it will take to complete the scan. The 

scanner can be set up out of the roadway and the roadway may be open to traffic while the scan 

is completed. However, items of evidence that are blocked by passing traffic may not be 

recorded.

Additionally, laser energy has a tendency to bounce off of shiny surfaces such as a vehicle body 

or absorbed by a black tire. When a return signal is missed because of poor reflectivity, no 

measurement is recorded and a hole is left in the point cloud. Typically, at a distance of 10 

meters, a point spread of 1⁄2 inch will take less than 4 minutes. This density spread is not 

acceptable for collision investigation because, at a distance of 100 meters, the point spread is 

nearly 4 feet. This issue may be eliminated by increasing the scan density which increases the 

scan time substantially. Similar to the total station, the 3-D Laser Scanner is a line of sight 

instrument and must be moved around the crash site repeatedly to complete data gathering. A 

single dome (360 degree) scan may contain several million measurements. Scenes documented 

using multiple scans must be registered or combined to facilitate measurement from one scan 

into another.

The use of 3-D Laser Scanning may be limited by weather conditions, such as rain that may 

reduce the quality of the scan. Like other types of technology, the investigator must be able to 

see what is being measured. While the at-scene time may be reduced by the use of 3-D Laser 

Scanning, the processing of the data for the purposes of reconstruction may be time consuming 

on the part of the investigator.
Crash Investigation and Reconstruction 40 U.S. Department of Transportation

Technologies and Best Practices Federal Highway Administration

Description: 3-D Laser Scanning

Using point cloud data collected from the laser 

scanner, investigators are able to develop highly 

detailed 3-D models for analysis. For example, 

lines of sight can be analyzed from various 

vantage points or the scan data may be compared 

with Original Equipment Manufacturer (OEM) 

CAD files for vehicle deformation analysis. 

Additionally, the scan data can also be used to 

create crash animations to simulate the actual 

event for use in the courtroom.

Average Cost: $48,000 – 58,000

Figure 10. Photo. Three-dimensional

Laser Scanning

Source: FARO Technologies and the Modesto 

Police Department

Technology Rating Index – as judged by the experts

Safe, Quick Clearance Responder Safety Court Acceptance

Table 20. How the Experts Rated Three-dimensional Laser Scanning

CRITERIA 1 2 3 4 5 TOTALS

Cost of Ownership 4 8 3 0 5 20

Availability 5 2 3 0 5 15

Amount of Training Required 0 8 6 4 0 18

Retraining to Continue Certification 1 2 3 8 5 19

Setup and Takedown 1 0 9 4 10 24

Opportunities for Enhancements 0 0 0 0 30 30

Court Acceptability 0 0 0 8 30 38

TOTALS 11 20 24 24 85 164

The following are comments provided by the reviewers about 3-D Laser Scanning:

• Responder Safety

• Reduces risk to investigators, reduces on-scene crash investigation time

• Allows the user to scan at a distance, out of harm’s way.

• Requires roadway to be closed if moderate to heavy traffic.

• Safe Quick Clearance

• Takes longer to scan scenes if detail (no gaps) desired. Enormous scene detail and 

topography information is captured. Sometimes low contrast evidence is not clear.

• Allows significant amount of data to be collected in a short period of time. 

Movements of the instrument for viewpoints sometimes increases time needed.

• Prompt, Reliable Communications

• Collects vast amounts of data which could be used for study purposes in the future.

• Proprietary software and doesn't work well with other programs. The technology is 

constantly improving.
Crash Investigation and Reconstruction 41 U.S. Department of Transportation

Technologies and Best Practices Federal Highway Administration

UNMANNED AERIAL SYSTEMS

Unmanned Aerial Systems (UAS) involve a remotely piloted aircraft carrying a precision highdefinition (HD) camera. The lightweight, multi-rotor aircraft takes off and lands vertically and is 

designed to fly under 400 feet Above Ground Level (AGL) to provide separation from manned 

aircraft.

The UAS are gaining acceptance in the field of traffic crash reconstruction. A flight conducted 

specifically for aerial mapping uses multiple technologies. The aircraft is designed to be reliable 

and maintainable by the user in compliance with accepted practices. Electrically-powered and 

highly maneuverable, a UAS uses a programmed Ground Control Point (GCP) or Real Time 

Kinematic (RTK) Global Positioning System (GPS) flight path. The area of interest is identified 

on an on-line, live map. The altitude assignment, flight path, and photography settings 

identification begins the initial mapping process. The flight path is calculated for current wind 

conditions for the most efficient flight path. Safety measures such as maintaining line of sight by 

a trained observer and the pilot utilizing a ground control station are included. Computermonitored battery power returns the aircraft to the take-off / safe landing position in the event 

that the batteries need to be charged or changed. Flight duration in most crash scene 

documentation cases will be well within battery capacity.

The flight computer controls stability during the flight. The camera’s gimbal mount provides 

assurance for stable geo-referenced photographs. As each photograph is recorded, the image is 

geo-tagged with precision measurements obtained by the on-board RTK GPS. For a multi-lane 

highway environment of 1000 feet in length, flight time estimates may last less than 10 minutes. 

The images may be examined at the scene following the flight to determine their suitability for 

post-crash photogrammetric analysis.

The time required to process the aerial images is dependent on computer processor speed. The 

final product is an orthomosaic map, digital terrain model and ultimately a point cloud similar to 

that created by the 3-D Laser Scanner.

The use of Unmanned Aerial Systems is regulated by the Federal Aviation Administration 

(FAA). Under the current conditions of most FAA-issued Certificates of Authorization (COA),

or 333 exemptions, the operator must be a private pilot to operate the system and be 

accompanied by an observer. The FAA continues to evaluate the integration of UAS into the 

national air space system. Efforts are under way to revise the requirements for operation and 

change is constantly monitored.

The final operating rules will require more training than is now required to become proficient 

with other types of technology given the aerial aspect of utilizing the NAS (National Air Space) 

to achieve the NUG and TIM goals. For example, the pilot / operator may be required to 

complete the ground school portion of flight training to receive a certificate to operate the 

system. Training to remain proficient in the use of the UAS and the software that is necessary to 

process the aerial images may be necessary. Proficiency may be gained and tracked by logged 

flight time by applied use or recurrent training.

The Unmanned Aerial Systems that are currently available range in price from approximately 

$2,000 to $65,000 or more with inclusion of the software. While the price is substantial, the 
Crash Investigation and Reconstruction 42 U.S. Department of Transportation

Technologies and Best Practices Federal Highway Administration

prices continue to decrease as the technology is more widely used. A summary of the costs of 

the equipment is provided in Table 29.

Table 21. Unmanned Aerial Systems Equipment and Costs

EQUIPMENT COST

Ground Control Point (GCP) Reference. $4,000 to $15,000

Consumer-grade systems. $2,000 to $6,000

Commercial grade Real Time Kinematic (RTK) Global 

Positioning System (GPS). Less than $40,000

The use of UAS will reduce the time needed for crash scene investigation. When a UAS arrives 

at the incident scene in a timely manner, mapping can usually be completed in a matter of 

minutes. These systems allow the crash scene to be mapped without personnel in the roadway 

exposed to the dangers of traffic. Mapping can completed while the roadway is open to traffic in 

some cases.

The use of Unmanned Aerial Systems may be limited by weather conditions. While some of the 

systems are resistant to weather, conditions such as fog, rain, snow, and high winds may make 

Unmanned Aerial Systems unsuitable for use. FAA regulations require that the Unmanned 

Aerial System be within line of sight of the operator. Special allowances may need to be 

addressed by the FAA to ensure safety and compliance with current rules. A well-selected 

control station should not limit the scene documentation process. Unmanned Aerial Systems 

reduce on-scene time and, properly prepared for, the post-crash data processing time is

comparable to a scene documented with a total station considering a comparable end product.
Crash Investigation and Reconstruction 43 U.S. Department of Transportation

Technologies and Best Practices Federal Highway Administration

Description: Unmanned Aerial Systems

Unmanned Aerial Systems (UAS), remotely piloted 

Aircraft, are rapidly growing in popularity in commercial 

applications. These devices are regulated by the FAA. 

The application to crash investigation comes by way of 

aerial mapping. The accuracy of this technology is 

dependent on altitude, camera resolution, flight planning 

software and weather. Geo-referenced photographs are 

used to create detailed 3-D point clouds, Digital Surface 

modeling and orthomosaic generation.

Average Cost: GCP $4000 – $15,000

RTK GPS Up to $65,000 Figure 11. Photo. Unmanned 

Aerial Systems

Source: Michigan DOT

Technology Rating Index – as judged by the experts

Safe, Quick Clearance Responder Safety Court Acceptance

Table 22. How the Experts Rated Unmanned Aerial Systems

CRITERIA 1 2 3 4 5 TOTALS

Cost of Ownership 0 2 15 4 0 21

Availability 3 4 3 0 5 15

Amount of Training Required 0 8 6 4 0 18

Retraining to Continue Certification 1 2 3 8 5 19

Setup and Takedown 0 0 6 8 15 29

Opportunities for Enhancements 0 0 0 0 30 30

Court Acceptability 0 2 0 8 10 20

TOTALS 4 18 33 32 65 152

The following are comments provided by the reviewers about Unmanned Aerial Systems:

• Responder Safety

• Decreases risk as UAS can be flown from off roadway.

• Improves responder safety since it can be used after the collision has been cleared.

• Reduces risk to investigators and on-scene investigation time.

• Safe Quick Clearance

• Rapidly documents collision and crime scenes and re-opens roadways in less time. 

FAA restrictions being interpreted.

• Quick method for documenting a scene.

• Allows the responder to take the scene back to the office for measurements.

• Prompt, Reliable Communications

• Data transformed via photogrammetry software. Once that is complete, data sets are 

easily transferred.

• Photos document how scene was actually cleared. Possible use for case studies.
Crash Investigation and Reconstruction 44 U.S. Department of Transportation

Technologies and Best Practices Federal Highway Administration

GLOBAL POSITIONING SYSTEMS

The Global Navigation Satellite Systems (GNSS) Systems make use of a satellite navigation 

system including the Navistar Global Positioning System (GPS) operated by the DOD or 

GLONASS operated by the Russian Aerospace Defense Force. The use of GPS Systems is 

commonly referred to as GPS mapping.

GPS Systems typically consist of two units. One is a rover and one is a base. The systems must 

have cellular access through a Data Collector to a GPS remote base station, or, if no cellular 

service is available, a second unit can be utilized as a base station. These units communicate 

with each other using a Class II Bluetooth connection that allows communication over a radius 

of approximately 1000 feet. This distance is usually great enough for use in completing 

investigations at most traffic crash scenes. A summary of the costs of the equipment is provided 

in Table 32.

Table 23. Global Positioning System Equipment and Costs

EQUIPMENT COST

Dependent upon type and model. $6,000 to $20,000

Data collector and Evidence Recorder. $2,400

Forensic Computer Aided Diagramming (CAD) Software. $1,000

Initially, the GPS Systems available for traffic crash reconstruction were expensive. However, 

there are units currently available that are much more affordable. The units that are available for 

traffic crash reconstruction are capable of centimeter accuracy when used in the carrier phase 

GPS mode. This level of accuracy supports the use of GPS Systems for crash reconstruction.

As with other complex technologies, training to become proficient in the use of GPS Systems is 

much more involved. The recommended basic training needed is a minimum of 40 hours and 

does not include field projects that should be completed following the basic course. In addition 

to the basic training and field projects, operators must use the equipment frequently to maintain 

their proficiency and maintain court acceptance. 

The introduction of a new Real Time Kinematic (RTK) GPS system has emerged. It offers a pair 

of GPS antenna, (base and rover) that utilize class 1 Bluetooth range. A complete RTK GPS 

system is now available for about 1⁄2 the cost of a radio controlled GPS system. This system 

requires nearly clear sky above the base and rover antenna. The system allows for one antenna 

to serve as the base unit. Up to three rovers may operate from the single base supporting a multidisciplinary approach to scene documentation. Crash scene investigation may be reduced by 

two-thirds with this application.
Crash Investigation and Reconstruction 45 U.S. Department of Transportation

Technologies and Best Practices Federal Highway Administration

Description: GPS Systems

GPS devices are everywhere and in many devices, 

including mobile phones. Recently, GPS 

receivers are also being used to provide essential 

data for crash reconstruction. Speed and vehicle 

position may be recorded if a GPS device is in use 

at the time a crash occurs. This data can then be 

used by analysts to determine a vehicle’s path and 

speed before, and even after a collision.

Average Cost: $7,000 – 30,000 Figure 12. Photo. Global Positioning

Systems 

Source: Missouri State Highway Patrol

Technology Rating Index – as judged by the experts

Safe, Quick Clearance Responder Safety Court Acceptance

Table 24. How the Experts Rated GPS Systems

CRITERIA 1 2 3 4 5 TOTALS

Cost of Ownership 0 4 6 4 15 29

Availability 1 0 3 12 15 31

Amount of Training Required 0 6 6 8 5 25

Retraining to Continue Certification 0 2 6 8 5 21

Setup and Takedown 0 2 6 4 20 32

Opportunities for Enhancements 0 4 3 0 25 32

Court Acceptability 0 2 3 4 25 34

TOTALS 1 20 33 40 110 204

The following are comments provided by the reviewers about Global Positioning Systems:

• Responder Safety

• Positive and negative attributes when it comes to Responder Safety. It is very easily 

used as a one person unit, however that person can become unaware of the hazards 

around them when their full attention is given to the operation of the unit. With that 

said, it greatly reduces the time spent on-scene over the Reflectorless and Robotic 

Total Stations.

• Safe Quick Clearance

• Set up time is low; scenes are cleared more quickly.

• Increases data collection speed; scene cleared much faster.

• Prompt, Reliable Communications

• Communications are not possible with satellites in some situations such as buildings, 

terrain, and foliage blocking sight line to satellites. There are places it cannot be 

used due to the line of sight obstructions.

• Information gathered is the same as the Total Stations and has the same ease and 

restriction on the sharing of the data.
Crash Investigation and Reconstruction 46 U.S. Department of Transportation

Technologies and Best Practices Federal Highway Administration

LIGHT DETECTION AND RANGING SYSTEMS

Light Detection And Ranging (LiDAR) has been used for traffic crash investigation and 

reconstruction for some time. LiDAR Systems consist of a LiDAR Unit and a Data Collector. A 

summary of the costs of the equipment is provided in Table 35. LiDAR is a remote sensing 

technology that measures distances by illuminating the target with a laser then analyzing the 

reflected signal to determine the distance. As a standalone device, the LiDAR will only measure 

slope distances. The addition of an angle encoder will allow recording of polar coordinates. The 

measurements recorded utilize an angle encoder much like those recorded by an Electronic Total 

Station. 

Table 25. Light Detection and Ranging Systems Equipment and Costs

EQUIPMENT COST

Light Detection and Ranging (LiDAR), Angle Encoder, and Software. $7,000

LiDAR is routinely used by law enforcement as a speed measuring tool. Distance measurement 

is a function of the LIDAR in calculating speed. The measurements necessary for traffic crash 

reconstruction use the laser to measure distance rather than speed. Measurements can be 

captured using a prism, reflectors, or they may be captured reflectorless. This data is used to 

create a map of the crash scene.

The use of LiDAR systems in traffic crash reconstruction is complex, much like the Electronic 

Total Station. The recommendation for the necessary basic training is a minimum of 40 hours

and does not include any field projects that should be completed following the basic course. In 

addition to the basic training and field projects, operators must use the equipment frequently to 

maintain their proficiency and maintain court acceptance.

The LiDAR can be handheld or tripod mounted. The tripod-mounted LiDAR Systems are 

recommended since errors may be introduced with handheld configurations due to the instability 

introduced by the human in the loop. Without mechanical stability and optical magnification, 

aiming to precision points may be difficult. Using the unit without a graphic controller may 

result in measurement errors. 

A technician using LiDAR may minimize personal exposure to traffic by carefully selecting the 

instrument location and recording measurements in the reflectorless mode. In the reflectorless 

mode, the mapping time may be lengthened as measurements are timed to be recorded between 

vehicles while the roadway is open to traffic. However, since these measurements are collected 

while the roadway is open to traffic, the effect on traffic flow is minimized.

The use of LiDAR Systems may be limited by weather conditions, with rain reducing the 

effective range. As with other technologies, the investigator must be able to see what is available 

for measurement. While the at-scene time decreases with the use of LiDAR Systems, the 

processing of the data for the purposes of reconstruction may be time-consuming on the part of 

the investigator. 
Crash Investigation and Reconstruction 47 U.S. Department of Transportation

Technologies and Best Practices Federal Highway Administration

Description: LiDAR Systems

LiDAR is a remote sensing technology that measures 

distance by illuminating a target with a laser and 

analyzing the reflected light. LiDAR is popularly 

used to make high-resolution maps.

Average Cost: Approximately $7000 with the 

LiDAR, Angle Encoder and Software

Figure 13. Photo. Light Detection and 

Ranging Systems 

Source: Laser Technology, Inc.

Technology Rating Index – as judged by the experts

Safe, Quick Clearance Responder Safety Court Acceptance

Table 26. How the Experts Rated Light Detection and Ranging Systems

CRITERIA 1 2 3 4 5 TOTALS

Cost of Ownership 0 6 6 8 0 20

Availability 1 0 9 8 5 23

Amount of Training Required 0 2 15 4 0 21

Retraining to Continue Certification 0 2 3 4 10 19

Setup and Takedown 2 0 6 12 0 20

Opportunities for Enhancements 2 2 3 4 0 11

Court Acceptability 0 0 3 12 15 30

TOTALS 5 12 45 52 30 144

The following are comments provided by the reviewers about LiDAR Systems:

• Responder Safety

• Allows for roadway mapping without being in the traffic.

• Allows for measurements across/away from moving traffic, reducing possible 

exposure.

• Safe Quick Clearance

• Clearance rates decrease for simple scenes. Clearance rates increase for complex 

scenes.

• Improves clearance times since some of the evidence can be measured after the 

roadway is open to traffic.

• Prompt, Reliable Communications

• Allows for very accurate measurements supporting detailed reports. 

• Supports information sharing with anyone who has compatible software.
Crash Investigation and Reconstruction 48 U.S. Department of Transportation

Technologies and Best Practices Federal Highway Administration

IMAGING STATIONS

The Imaging Station is essentially a Robotic Total Station with a built-in camera which adds the 

ability to intelligently scan an area visible through the camera lens. An area of interest is 

identified by aiming the internal camera. Once selected, the software predicts points that will 

need to be measured to model the observation. After the establishment of a prediction, the 

operator may remove points from or add points to the prediction selection and begin the scanning

process. 

The Robotic Total Station followed as a variant of the Electronic Total Station, and has been in 

use for traffic crash reconstruction in the United States for some time. The Robotic Total Station 

is comprised of five components. These components are the Motorized Theodolite, Electronic 

Distance Measurement (EDM) Instrument, Optical Prism, Data Collector, and a Remote 

Controller. In addition to these components, the Imaging Station incorporates a through-the-lens 

digital camera. The Imaging Station utilizes the principles of surveying to create a map of a 

crash scene. A summary of the costs of the equipment is provided in Table 38.

Table 27. Imaging Stations Equipment and Costs

EQUIPMENT COST

Imaging Station with Motorized Theodolite, Electronic Distance 

Measurement Instrument, internal camera, optical Prism, remote controller,

and essential accessories (tripod, prism pole(s), tape measure, and Software).

$36,000

Data Collector and Evidence Recorder. $2,400

Like the Robotic Total Station, the Imaging Station eliminates the need to mechanically aim the 

EDM at the prism. Auto-tracking the prism via a remote controller is a function of the Imaging 

Station. The controller functions to re-establish tracking of the prism more efficiently. A search 

command sent from the remote controller to the command station turns the station to the prism

eliminating the need to manually aim the station at the prism and return to the prism lock status.

The use of a tracking laser maintains aim automatically and updates distance measurements. The 

Robotic variant increases the ability to measure in the reflectorless mode to 2000 meters or 

approximately 6,500 feet. These distances are to an industry standard grey card. When 

measuring to a roadway from ground level, a user should expect maximum measurements to 

about 2,000 feet, which is sufficient to cover a 1⁄4 mile crash site. The measurement time 

decreases as the instrument is constantly measuring and updating the collector.

The station is motorized horizontally and vertically. As the laser tracks the prisms’ movement 

about the scene, the need to precisely focus and aim the station is eliminated. The addition of a 

remote controller provides the option for one-person operation at incident scenes. The data 

collector connects to the remote controller which then connects to the unit via long range 

Bluetooth. Should connection be lost, the remote controller provides a method to reconnect the 

devices.

The theodolite is a very precise instrument used to measure horizontal and vertical angles 

between points. The EDM measures the slope distance between points. The Electronic Total 
Crash Investigation and Reconstruction 49 U.S. Department of Transportation

Technologies and Best Practices Federal Highway Administration

Station utilizes an infrared light laser reflected from an optical prism to capture distances. This 

data maintains attributes recognized by the software. The data is input to software designed for 

creating a scale map and is a visual depiction of the crash scene. The gathered data is used in 

mathematical formulas to reconstruct the crash.

As with the use of the other variations of the Electronic Total Station, the Imaging Station is 

more complex and the training is much more involved. The recommendation of basic training 

needed is a minimum of 40 hours and does not include field projects that should be completed 

following the basic course. In addition to the basic training and field projects, operators must use 

the equipment frequently to maintain their proficiency and maintain court acceptance. 

Like other variations of the Electronic Total Station, the technician utilizing an Imaging Station 

can minimize exposure of personnel to the dangers of traffic by carefully selecting the instrument 

location. 

When an Imaging Station arrives at the incident scene in a timely manner, the mapping of the 

scene can usually be accomplished by the time vehicle removal is complete. In cases where 

points of evidence remain for measurement, the reflectorless configuration is available to 

complete the work. The selection of the reflectorless option increases the mapping time as 

measurements are timed to be recorded between vehicles while the roadway is open to traffic. 

However, since these measurements are collected while the roadway is open to traffic, the effect 

on traffic flow is minimized.
Crash Investigation and Reconstruction 50 U.S. Department of Transportation

Technologies and Best Practices Federal Highway Administration

Description: Imaging Stations

Imaging Stations combine advanced imaging and 

high-accuracy surveying, incorporating real-time 

field imagery with spatial data. Powerful 

functionality is controlled using software that 

produces "photography with dimension", a 

revolutionary and cost effective alternative to laser 

scanning.

Average Cost: $20,000

Figure 14. Photo. Imaging Stations

Source: TOPCON

Technology Rating Index – as judged by the experts

Safe, Quick Clearance Responder Safety Court Acceptance

Table 28. How the Experts Rated Imaging Stations

CRITERIA 1 2 3 4 5 TOTALS

Cost of Ownership 2 0 0 4 5 11

Availability 3 0 0 0 5 8

Amount of Training Required 0 2 3 0 5 10

Retraining to Continue Certification 0 2 3 0 0 5

Setup and Takedown 0 4 3 0 0 7

Opportunities for Enhancements 1 0 3 0 5 9

Court Acceptability 0 0 0 0 20 20

TOTALS 6 8 12 4 40 70

The following are comments provided by the reviewers about Imaging Stations:

• Responder Safety

• Allows options for the operator to measure either remotely or from the base. As 

long as the scene is controlled, the operator remains relatively safe from exposure.

• Requires the roadway to be kept closed, decreasing safety.

• Safe Quick Clearance

• Enhances TIM quick clearance.

• Prompt, Reliable Communications

• Provides for vast amounts of data which can be analyzed in the future.
Crash Investigation and Reconstruction 51 U.S. Department of Transportation

Technologies and Best Practices Federal Highway Administration

CHAPTER 6 VIRTUAL DEMONSTRATIONS

Four web-based virtual demonstrations were conducted to present the technologies and usage in 

compliance with the National Unified Goal for Traffic Incident Management (NUG). These 

were visual representations of the research results. The demonstrations were used to gather more 

detailed information and to allow the Federal Highway Administration (FHWA) Government 

Task Manager, the Expert Panel, and the project team to interact with the contributors of the best 

practices and technologies. The demonstrations also allowed for follow-up questions regarding 

the practices, technologies, and lessons learned.

The Team worked with manufacturers and vendors to develop demonstrations utilizing slide 

presentations, supplemented with video of the methods in use. They were designed to describe 

the type of technology, ease of set-up, application, and the capabilities provided for law 

enforcement agencies and reconstruction professionals. The presenters provided information 

regarding the training requirements, costs to acquire, costs to maintain, and the expected service 

life.

The demonstrations detailed the technology applications as a part of a Traffic Incident 

Management program including the best use of the methods to provide a safer working 

environment for responders and motorists, and to minimize the time that roadways are closed 

due to crash reconstruction.

The demonstrations included presentations on the:

• Electronic Total Station,

• Reflectorless Electronic Total Station,

• Semi-Robotic Total Station,

• Robotic Total Station,

• Total Station Hybrid,

• 3-D Laser Scanning,

• Photogrammetry,

• Unmanned Aerial Systems,

• GPS Systems

The virtual demonstrations helped the team categorize technologies into three groups –

compliance with NUG goals, cost, and availability. When reviewing results, the reader must 

accept the assumption that the best method for compliance with the NUG may not be readily 

available and the cost may be a factor. Likewise, technology that is relatively low cost may not 

allow for compliance with the NUG due to increased exposure of personnel and extended lane or 

roadway closures.
Crash Investigation and Reconstruction 52 U.S. Department of Transportation

Technologies and Best Practices Federal Highway Administration

Several of the technologies reviewed in the Virtual Demonstrations allude to the use of the 

technology by one officer or operator. While technically the equipment may be utilized by one 

officer or operator, this approach is not advised due to safety concerns. There is a need for 

assistance in the investigations to protect personnel from the dangers of traffic. Personnel focus 

their efforts on the task at hand and may not be able to concentrate on the traffic and other 

activity around them. It is essential that additional personnel assist with the investigation or 

provide back-up in the form of extra eyes and ears at the scene of an incident.
Crash Investigation and Reconstruction 53 U.S. Department of Transportation

Technologies and Best Practices Federal Highway Administration

CHAPTER 7 CONCLUSIONS

The research into the state-of-the-practice and the evolution of technologies in traffic crash 

reconstruction leads to a predictable conclusion – selection or upgrades of technology will be 

specific to each individual agency or interagency need. The needs of an agency for crash 

reconstruction equipment must be conveyed to those with funding to potentially support the 

acquisition, operation, training and maintenance of the equipment. The needs should be 

expressed in terms of benefits and a case made that matches the need with the type of equipment 

requested. As stated earlier, the dangers to personnel are great and the cost of congestion is 

rising. Acquiring the best method that minimizes the exposure of personnel to traffic while 

minimizing the cost to society should be a part of the business case for traffic crash 

reconstruction technology.

This report is the result of a process of data gathering, analysis, and evaluation of best practices 

and technology in use today and those that are emerging in the crash reconstruction environment. 

The information provided in this report should be useful to agencies who have defined a need for 

crash reconstruction equipment to improve responder and investigator safety at the scene, to 

collect court acceptable data about the crash event, and to minimize the impact of crash 

reconstruction data gathering on the flow of traffic. Matching agency needs with available 

funding is almost always a challenge. The benefits and advantages of each of the technologies 

described in this report will provide an agency with information they need to develop 

justification for a solution to their crash reconstruction needs. 

Agencies and organizations must examine their needs and resources when making the decision to 

acquire or upgrade traffic crash reconstruction equipment. The goal is to have the equipment 

readily available for response to an incident. If the equipment is not readily available the safety 

of personnel and motorists can be compromised due to extended roadway closures. While the 

use of Unmanned Aerial Systems appears to be the safest, with the least amount of time 

necessary to gather the data required for an accurate reconstruction, it is of little use if 

unavailable or the response time is high. Law enforcement agencies may find that, due to 

funding and resources, training officers to properly mark and photograph items of evidence at an 

incident scene and equipping them with quality digital cameras may be the safest and most 

efficient answer to their needs. This approach would reduce the time that roadways are closed

and would allow for more technical investigative techniques to be utilized when it can be done 

safely. No matter what technology or procedures are used, personnel must be properly trained 

and competent in its use for court acceptance.

There is no one-size-fits-all solution in traffic crash reconstruction. Each agency should examine 

their activities and resources to decide what is best for their environment. It is recommended 

that an agency familiarize themselves with the practices and technologies presented in this report 

and identify those that best match their organizational practices, requirements, and needs. The 

benefits and budgetary information provided for each method can then be used to justify 

expenditures or negotiate budget for purchase, training, operation and maintenance of the 

system. Each agency will have a different traffic environment, organizational structure, political 

establishment, and funding constraints. This report collects crash reconstruction technology and 

best practices data to inform those decisions.

Crash Investigation and Reconstruction 55 U.S. Department of Transportation

Technologies and Best Practices Federal Highway Administration

APPENDIX A: EXPERT PANEL BIOGRAPHIES

Each of the Expert Panel members was contacted for input in this project. The needs of the 

project were explained to them, with the need for expert participation emphasized. The panelists 

participated in conference calls, as well as completing a survey concerning the technology that 

they use or are familiar with, and how well the technology supported the goals of the National 

Unified Goal for Traffic Incident Management (NUG). The experience of the panelists 

determined which technologies would be examined in the virtual demonstrations.

Mike Anderson

Michael Anderson is employed by the Unified Police Department of Greater Salt Lake, in Salt 

Lake City, Utah. Prior to the unification of the Department, Michael was a member of the Salt 

Lake County Sheriff’s Office. He has been employed by the Salt Lake County Sheriff’s Office / 

Unified Police Department of Greater Salt Lake for 20 years. For the last 15 years he has been 

assigned to the Major Crash Unit, or as the unit is now known, the Collision Analysis 

Reconstruction (CAR) Unit. Michael is the senior member of the CAR Unit team. He is 

responsible for the funding, grant application and administration, training and equipment updates 

for the Unit. The CAR Unit is responsible for the investigation and reconstruction of serious 

injury and fatal crashes in the jurisdictions served by the Unified Police Department of Greater 

Salt Lake. Michael Anderson is certified by the Accreditation Commission for Traffic Accident 

Reconstruction (ACTAR). He has been certified by ACTAR for over six years. Michael has 

taught crash investigation courses for Northwestern University in the past and he currently 

provides law enforcement training on traffic safety related topics which includes crash 

investigation training at the advanced level.

James D. (Dave) Bean

James D. (Dave) Bean is currently a Crash Investigation Specialist at the United States 

Department of Transportation/the National Highway Traffic Safety Administration. He is a 

retired Police Detective from the Fairfax County Police Department, in Fairfax, Virginia. Dave 

has 29 years of law enforcement experience.

Dave has previously been designated as the Fairfax County Police Officer of the Year and a past 

award winner of the International Association of Chiefs of Police, J. Stannard Baker Award for 

Highway Safety.

Dave Bean is also a founding member of the Fairfax County Police Crash Reconstruction 

Section and has been assigned to the unit for the last 17 years of his career as a law enforcement 

officer.

Victoria (Tori) Boldt

Employed by the Sarpy County Sheriff’s Office, in Papillion, Nebraska, Victoria (Tori) Boldt 

specializes in Accident Reconstruction for the Sarpy County Sheriff’s Office. She participates in 

a county wide crash response team providing crash investigation and reconstruction services for 

six law enforcement agencies in the county.
Crash Investigation and Reconstruction 56 U.S. Department of Transportation

Technologies and Best Practices Federal Highway Administration

Tori Boldt has been employed by the Sarpy County Sheriff’s Office for eleven years, and has 

served as a Crash Investigator for ten years. Receiving hundreds of hours of crash specific 

training, Tori is responsible for the investigation and reconstruction of serious and fatality 

crashes for the Sarpy County Sheriff’s Office. 

Tori Boldt received accreditation through ACTAR in 2009. In addition, Tori provides Crash 

Investigation training at the Nebraska Law Enforcement Training Center.

Tracy Flynn

Tracy Flynn began his career with the Pennsylvania State Police in September 1995. He was 

promoted to Corporal in 2011. Tracy received training in traffic crash reconstruction in 2007 

and he received his ACTAR accreditation in 2012. Tracy is currently assigned to the Bureau of 

Patrol for the Pennsylvania State Police. He is currently the Collision Analysis and 

Reconstruction Specialist Unit Supervisor and has held that position since of 2012. In his career, 

Tracy Flynn has been involved in the investigation and reconstruction of a large number of 

crashes.

John Graves

John Graves has been employed by the Hillsborough County Sheriff’s Office since 1996. He is 

currently assigned as a Master Detective with the Traffic Homicide Section of the Hillsborough 

County Sheriff's Office Department of Investigative Services which he has served since 2005. 

John has received over 600 hours of traffic crash investigation training and has over 13 years of 

traffic crash reconstruction experience which has qualified him to testify as an expert in criminal 

court in the field of Traffic Homicide Reconstruction. 

Crashes that involve criminal charges and civil court cases are investigated by the Traffic 

Homicide Section of the Hillsborough County Sheriff's Office Department of Investigative 

Services. The Traffic Homicide Detectives collect the evidence, photograph and map the scene, 

and conduct the reconstruction of the events that led up to the crash. The skills of the Traffic 

Homicide Detectives are often called upon during the investigation of other criminal cases. 

John Graves has received training in Advanced Scene Investigation Using Forensic Mapping and 

CAD from Texas A&M University. He has also received training in Photographic Techniques 

for Crash Investigations from the Florida Public Safety Institute. John Graves also received 

certification from the Accreditation Commission for Traffic Accident Reconstruction (ACTAR) 

in 2007. 

Gregory Gravesen

Greg Gravesen began his career in vehicle crash reconstruction in 1992. He holds a Bachelor of 

Science degree in Criminal Justice from the University of Wisconsin – Platteville. Greg has 24 

years of law enforcement experience and is currently a Sergeant with the St. Paul Police 

Department’s Forensic Services Unit. 

Greg is an ACTAR certified Accident Reconstructionist with specialized training from 

institutions such as the Institute of Police Technology and Management (IPTM) at the University 

of North Florida, Northwestern University Traffic Institute, and several others. Greg is also an 
Crash Investigation and Reconstruction 57 U.S. Department of Transportation

Technologies and Best Practices Federal Highway Administration

adjunct instructor for IPTM with both the Basic and Advanced Pedestrian and Bicycle 

Reconstruction courses and Advanced Crash Reconstruction using HVE-CSI. 

Greg has testified many times in trials and depositions, and has been qualified as an expert in the 

fields of Accident Reconstruction, Forensic Mapping and Forensic Animation in both State and 

Municipal courts. Greg specializes in vehicle crash investigation and reconstruction, pedestrian 

crash reconstruction, computer simulation & animation, and forensic mapping and scanning. In 

addition, Greg Gravesen owns and operates a crash analysis consulting business. 

Ronald B. Heusser

Ron Heusser received a Bachelor of Science degree in Mechanical Engineering in 1970 from 

Oregon State University. He has worked as a Civil Engineer for the U. S. Forest Service. Ron 

has been involved in the business of crash reconstruction for over 29 years.

Ron was employed by the National Transportation Safety Board (NTSB) for over 7 years. Ron’s 

experience with the NTSB included on-scene investigations, crash reconstruction, and report 

writing. He also served as both Vehicle and Highway Group Chairman for several major crash

investigations for the NTSB.

Since July 1992, Ron has been working his own accident analysis company. Ron wrote two 

Society of Automotive Engineers (SAE) papers on heavy truck braking and he co-authored a 

major safety study for the NTSB on air brake performance. Ron has taught truck reconstruction 

courses for state police agencies in Pennsylvania, Michigan, Oregon, North Dakota and 

Washington. Ron has taught for the Department of Continuing Education at Arkansas State 

University and the Engineering Extension Service at Texas A&M University.

Keith Jackson

Keith Jackson is currently employed by the Collinsville Police Department in Illinois. He has 

been in law enforcement for about 8 years and is currently assigned to the Street Crime Unit at

the Collinsville Police Department. Keith has received law enforcement-related training as a 

Field Training Officer, DUI Enforcement, Search and Seizure, Crime Scene Processing, Traffic 

Crash Reconstruction and Investigations, as well as other law enforcement training. 

Keith Jackson received certification as an Illinois Certified Traffic Accident Reconstruction 

Specialist in the summer of 2012 from the Illinois Law Enforcement Training and Standards 

Board. He has received additional training in Motorcycle Crash Reconstruction, Pedestrian 

Crash Reconstruction, Crash Reconstruction/Crime Scene Photography, Mapping and 

Diagramming, and Human Factors. 

Keith Jackson is certified by the Accreditation Commission for Traffic Accident Reconstruction 

(ACTAR). He has been a member of the Illinois Association of Technical Accident 

Investigators since 2012 and has attended the annual conference both years. 

In 2013, Keith assisted in forming the Metro East Crash Assistance Team to provide traffic crash 

reconstruction services to law enforcement agencies in three counties of southwest Illinois. This 

team includes certified accident reconstruction officers from various local agencies, and provides 

crash reconstruction services at no cost to the requesting agencies. Keith Jackson has been 
Crash Investigation and Reconstruction 58 U.S. Department of Transportation

Technologies and Best Practices Federal Highway Administration

involved in the reconstruction of approximately 25 to 30 traffic crashes, as well as many other 

serious crashes during his career. 

Matthew S. Jackson, Esq.

Matthew S. Jackson grew up with crash reconstruction and joined a private reconstruction firm, 

full-time in 2008, after graduating from law school. Since that time, he’s received formal and on 

the job training from the best in the field. He has assisted in the investigation and reconstruction 

of over 200 crashes and handles all aspects of ground vehicle crash reconstruction. Matthew has 

over 6 years of full-time Accident Investigation/Reconstruction experience, and also obtained his 

Accreditation Commission for Traffic Accident Reconstruction (ACTAR) certification.

Walter W. “Bill” Johnson

Walter W. “Bill” Johnson is a Master Police Officer assigned to the Traffic Investigation Unit of 

the Kansas City Missouri Police Department (KCPD). With 27 years of law enforcement 

experience, he has been assigned to the KCPD Traffic Investigation Unit, Accident Investigation 

Section, as an Accident Reconstruction Specialist for over 15 years. Bill has received extensive 

training in Traffic Crash Reconstruction, Forensic Mapping, and Traffic Incident Management. 

Bill has been fully accredited as a Traffic Crash Reconstructionist by the Accreditation 

Commission for Traffic Accident Reconstruction (ACTAR) since 2004. Bill is certified as a 

Level One Commercial Vehicle Inspector by the Commercial Vehicle Safety Alliance and has 

received specialized training in the investigation and reconstruction of crashes involving 

commercial motor vehicles. He is a current member of the Illinois Association of Technical 

Accident Investigators. Bill has been recognized as an expert in traffic crash reconstruction in 

both criminal and civil courts. Bill has been an active partner in the Kansas City Area Traffic 

Incident Management Program since its inception in 2007. With a focus on safe, efficient quick 

clearance, and concentration on the National Unified Goal, Bill has worked diligently with the 

many emergency response partners in the Kansas City Metropolitan area to develop and promote 

responder safety and Traffic Incident Management procedures throughout the Kansas City 

Metropolitan area. 

David Keltner

Dave Keltner is a Master Sergeant with the Illinois State Police. He currently serves as the 

Traffic Crash Reconstruction Unit’s (TCRU) Northern Illinois Supervisor. He has been an 

Illinois State Police certified Reconstruction officer since January 2002. The ISP Northern 

Illinois Reconstruction Team investigates an average of 150 fatal crashes a year. He has 

personally been the lead investigator on over 200 cases in the last decade. In June 2002, he was 

certified by the Illinois Law Enforcement Training and Standards Board (ILETSB) as a Crash 

Reconstruction Specialist. He is also certified by Accreditation Commission for Traffic 

Accident Reconstruction (ACTAR). Dave has over 2,400 hours of crash investigation training 

along with additional extensive training in critical incident management.

Dave is certified as an instructor by the ILETSB. He instructs Basic Crash Investigation, AtScene Crash Investigation, Technical Crash Investigation, Vehicle Dynamics, Crash 

Reconstruction, Traffic Incident Management and Roadway Safety Assessments. He continues 

to participate in speaking engagements around the region pertaining to crash investigation and 

scene and case management. He is a member of numerous professional organizations regionally 
Crash Investigation and Reconstruction 59 U.S. Department of Transportation

Technologies and Best Practices Federal Highway Administration

and nationally. Dave is currently in his second term as President of the Illinois Association of 

Technical Accident Investigators (IATAI).

Andrew S. Klane

Lieutenant Andrew S. Klane has been a member of the Massachusetts State Police for 

approximately 26 years. He has been assigned to the Collision Analysis and Reconstruction 

Section (CARS) for the past 22 years. Lt. Klane has reconstructed over 500 serious injury and 

fatal motor vehicle crashes. He has testified numerous times as an expert witness in both District 

and Superior Courts throughout the Commonwealth. Lt. Klane is accredited by the

Accreditation Commission for Traffic Accident Reconstruction (ACTAR). Lt. Klane is an 

instructor in the field of crash investigation for the Massachusetts State Police and the Criminal 

Justice Training Council. Since his promotion to the rank of Lieutenant in September 2009, Lt.

Klane has been the Section Commander of CARS. He is responsible for the Massachusetts State 

Police’s entire reconstruction program and for the supervision of four Sergeants and 18 Troopers 

that are assigned to the Section. Lt. Klane has been responsible for the selection and 

implementation of technology to facilitate CARS achieving the Department’s quick clearance 

goals, which he participated in developing. Lt. Klane represents the Massachusetts State Police 

on the Commonwealth of Massachusetts Traffic Incident Management (TIM) Task Force. HE

was a principle party in the drafting of the Commonwealth’s uniform response manual (URM).

Annjanette (Angie) Kremer

Angie Kremer received a Bachelor of Science Degree from Michigan Technological University 

in Civil Engineering and is a registered Professional Civil Engineer in the State of Michigan. 

Angie serves as the Traffic Incident Management (TIM) Engineer for the Michigan Department 

of Transportation (MDOT). She oversees the areas of TIM and Work Zone Safety & Mobility 

and her responsibilities include policies, procedures, and programs for MDOT related to these 

areas. Angie teaches classes/workshops to emergency personnel for responder safety, quick 

clearance and traffic incident management techniques. She is also an advisor for the national 

TIM Network and is Co-chair of the Michigan Traffic Incident Management Team for the 

Governor’s Traffic Safety Advisory Commission. 

Prior to her current position, Angie worked as the Traffic and Safety Engineer for the Marshall 

Transportation Service Center (TSC) with the Michigan Department of Transportation (MDOT). 

While working in that position, Angie’s duties brought together roles of the traditional traffic & 

safety areas along with a new focus of operations. Angie’s other areas of work expertise include 

the areas of Utilities, Permits, and Planning.

Angie is one of two representatives for MDOT on the ENTERPRISE Pooled Study for Rural 

Intelligent Transportation Systems (ITS). She is also a member of the Michigan Chief of Police 

– Safety Committee and on the Michigan Association of Traffic Accident Investigators 

(MATAI). Angie is also the only representative for transportation on the International 

Association of Chiefs of Police for the TIM Sub-Committee.
Crash Investigation and Reconstruction 60 U.S. Department of Transportation

Technologies and Best Practices Federal Highway Administration

Brian Reeves

Brian Reeves is a Traffic Accident Reconstructionist and has been investigating crashes since 

1994. He began his career with the Warrensburg Missouri Police Department in 1994. In 1998, 

Brian became a member of the Springfield Missouri Police Department. 

Since Brian began his career, he has investigated well over 1,000 non-injury and injury crashes. 

In 2008, Brian was assigned to the Traffic Section at the Springfield Police Department where 

his responsibilities were focused on traffic-related activities only. Since he began the specialized 

assignment in the Traffic Section, he has taken on the added responsibility of being the lead 

investigator in several fatality crashes. In addition, he has assisted with several other fatal crash 

investigations. 

Prior to this specialized assignment, Brian had been assigned to a Driving While Intoxicated 

Enforcement Team. During this assignment of three years, he received a Command 

Commendation for his efforts along with recognition by National Highway Traffic Safety 

Administration (NHTSA) and Mothers Against Drunk Driving (MADD). 

After being assigned to the Traffic Section, Brian earned his ACTAR Accreditation and has 

since been placed on the ACTAR Governing Board of Directors. Since 2008, Brian has been 

called to testify regarding his investigative findings in both criminal and civil court. He has 

continued his training by receiving considerable instruction since becoming a Reconstructionist. 

This training has included MapScenes Capture, Commercial Motor Vehicle Accident 

Investigation, and Total Station training. 

Brian has been imparting his knowledge to others by instructing at the Safety Center at the 

University of Central Missouri in Warrensburg, Missouri. He also assists attorneys and 

insurances companies by reviewing cases and providing crash reconstruction services through a 

private firm. 

Nathan Shigemura

Nathan Shigemura is certified as an Accident Reconstructionist by the State of Illinois and holds 

full accreditation as a Traffic Accident Reconstructionist from the Accreditation Commission for 

Traffic Accident Reconstruction (ACTAR). He is co-owner of a traffic crash reconstruction and 

analysis company based in Illinois.

Nathan Shigemura retired in 2002 as a sergeant from the Illinois State Police, where his duties 

included Crash Investigation Instructor, Traffic Crash Reconstructionist and Supervisor of the 

Statewide Traffic Crash Reconstruction Unit.

Since 1989, Nathan Shigemura has been an adjunct faculty member of the Institute of Police 

Technology and Management (IPTM) for whom he teaches courses in all levels of traffic crash 

investigation and reconstruction worldwide.

Nathan Shigemura received a Bachelor of Science degree in Electrical and Electronic 

Engineering (BSEE) from the University of Illinois, Chicago in 1975. Prior to joining the 

Illinois State Police, Nathan was employed as a hardware/software design engineer.
Crash Investigation and Reconstruction 61 U.S. Department of Transportation

Technologies and Best Practices Federal Highway Administration

Nathan Shigemura is a member and past president of Illinois Association of Technical Accident 

Investigators IATAI. Nathan is also an active member of the Society of Automotive Engineers 

(SAE) and the Fraternal Order of Police.

Nathan Shigemura is the author of Mathematics for the Traffic Accident Investigator and 

Reconstructionist, published by IPTM in 1996. He is a co-author, with John Daily, of 

Fundamentals of Applied Physics for Traffic Accident Investigators; Volume 1 of the Traffic 

Accident Reconstruction Series published by IPTM in 1997. And he is co-author, with Andrew 

Rich, of Balancing Collision Forces in Crush/Energy Analyses published by IPTM in 2007.

Thomas Simon

In June of 2007, Thomas Simon was promoted to Sergeant by Arizona Department of Public 

Safety (DPS) and reassigned to a Phoenix Highway Patrol squad, responsible for patrolling 

during the third shift in the Metro Central District. During this assignment, Simon supervised 6-

8 Highway Patrol officers as they investigated numerous high profile arrests, collision 

investigations involving felony charges, and an extraordinary amount of impaired driver 

investigations. Simon supervised the patrol squad until November 2012, when he was selected 

as a Sergeant in the Vehicular Crimes Unit (VCU) within the Major Crimes District, where he 

remains assigned. Thomas Simon has attended many advanced level collision investigation and 

reconstruction courses, interview and interrogation, Electronic Data Recorder and Drug 

Recognition Expert courses. He also prepares and presents training to new officers at the DPS 

Advanced Academy as well as other law enforcement agencies throughout Arizona. 

Presently, the DPS VCU uses a GPS-based station, an Imaging Station and a 3-D Laser Scanner 

in conjunction with software for collision and crime scene mapping. 

Scott Skinner

Scott Skinner is currently employed by the Oregon State Police, as the Statewide Collision 

Reconstruction Program Coordinator for the Oregon State Police. His current rank is Sergeant 

and he is stationed in Ontario, Oregon. His current assignment allows him to work full-time as a 

Collision Reconstructionist. He is responsible for managing the Collision Reconstruction Unit of 

the Oregon State Police and its 40 program members. He also peer reviews many of the collision 

reconstruction reports that are prepared by Oregon State Police officers statewide. Scott has 

been a sworn Oregon State Police officer since June 17, 1985. Scott holds an Associate of 

Science degree in Criminal Justice and Law Enforcement. He also holds an Advanced Law 

Enforcement Certificate from the Board of Public Safety Standards and Training. Scott received 

his initial training in the field of Collision Reconstruction from the Institute of Police 

Technology and Management (IPTM.), University of North Florida in 1993. He has been 

accredited by the Accreditation Commission for Traffic Accident Reconstruction (ACTAR) 

since October 1994. Scott continues to be accredited and in good standing with ACTAR, by 

maintaining at least the minimum requirement of 80 continuing education units every 5 years.

Crash Investigation and Reconstruction 63 U.S. Department of Transportation

Technologies and Best Practices Federal Highway Administration

APPENDIX B: TECHNOLOGY RANKINGS

As a part of this project, each technology was rated on Responder Safety, Quick Clearance, and

Court Acceptance. From the information developed during the research, including the surveys 

and the Virtual Demonstrations, the technology was ranked in each of these categories.

Due to the difference in the evaluation criteria in each category, each type of technology received 

a different rating in the following ranking, according to the National Unified Goal for Traffic 

Incident Management (NUG). Reviewer comments are provided in support of each criteria.

RANKING IN ORDER

1. Unmanned Aerial Systems (UAS).

a. Responder Safety.

i. Decreases risk of injury since UAS can be flown from off the roadway.

ii. Improves responder safety since it can be used after the collision has been 

cleared.

iii. Lowers risk to investigators by reducing on-scene crash investigation 

time.

b. Safe Quick Clearance.

i. Has the potential to rapidly document collision and crime scenes and reopen roadways in far less time that is currently experienced.

ii. One of the quickest methods of documenting scenes.

iii. Measurements can be made at an office location without being on the 

roadway.

c. Prompt, Reliable Communications.

i. Data transforms via photogrammetry software. Once that is complete, 

data sets easily transfer.

ii. Photos may document how the scene was actually cleared.

2. Reflectorless Electronic Total Station.

a. Responder Safety.

i. Optimal, fairly available measurement device. In many cases, enables 

measurements to be taken some distance from the roadway and out of 

traffic.

ii. Lowers exposure risk since no officer need be in the roadway.

iii. Reduces on-scene crash investigation time.
Crash Investigation and Reconstruction 64 U.S. Department of Transportation

Technologies and Best Practices Federal Highway Administration

b. Safe Quick Clearance.

i. Allows relatively quick scene clearances, compared to tape measures, etc. 

Captures scene detail required for diagrams and reconstruction analysis.

ii. Reduces time necessary to set up and take down, as well as reduced time 

to measure; all reducing time to return to a normal traffic pattern.

c. Prompt, Reliable Communications.

i. Data is easy to share.

ii. Information can be shared with anyone who has a compatible program that 

will communicate with the total station.

3. Semi-Robotic Total Station.

a. Responder Safety.

i. Risk and exposure to traffic is less than mechanical and Electronic Total 

Station. User can set up in a safe area and avoid traffic.

ii. Reduces risk to investigators, reduces on-scene crash investigation.

iii. Reduces on-scene crash investigation time.

b. Safe Quick Clearance.

i. For closed scenes, shaves time off the already quick clearance time of 

other total station instruments by cutting out the need to find and focus on 

areas of interest through scope.

ii. Set up can be heavily dependent on the individual operator's expertise in 

using it. For those properly trained, set up is not time-consuming and 

subsequent measurements can be taken quickly and with more precision 

and accuracy than the roller wheel or tape methods.

iii. Captures scene detail required for diagrams and reconstruction analysis.

iv. Reduces time necessary to set up and take down, as well as reduced time 

to measure; all reducing time to return to a normal traffic pattern.

c. Prompt, Reliable Communications.

i. Data is easy to share.

ii. Information can be shared with anyone who has a compatible program that 

will communicate with the total station.

4. Robotic Total Station.

a. Responder Safety.

i. Less risk and exposure to traffic than mechanical and Electronic Total 

Station. User can set up in a safe area and avoid traffic.

ii. Reduces risk to investigators, reduces on-scene crash investigation.

iii. Reduces on-scene crash investigation time.
Crash Investigation and Reconstruction 65 U.S. Department of Transportation

Technologies and Best Practices Federal Highway Administration

b. Safe Quick Clearance.

i. For closed scenes, shaves time off the already quick clearance time of 

other total station instruments by cutting out the need to find and focus on 

areas of interest through scope.

ii. Set up can be heavily dependent on the individual operator's expertise in 

using it. For those properly trained, set up is not time-consuming and 

subsequent measurements can be taken quickly and with more precision 

and accuracy than the roller wheel or tape methods.

iii. Captures scene detail required for diagrams and reconstruction analysis.

iv. Reduces time necessary to set up and take down, as well as reduced time 

to measure; all reducing time to return to a normal traffic pattern.

c. Prompt, Reliable Communications.

i. Data is easy to share.

ii. Information can be shared with anyone who has a compatible program that 

will communicate with the total station.

5. Hybrid Total Station.

a. Responder Safety.

i. Less risk and exposure to traffic than mechanical and electronic total 

station. User can set up in a safe area and avoid traffic.

ii. Reduces risk to investigators, reduces on-scene crash investigation.

iii. Reduces on-scene crash investigation time.

b. Safe Quick Clearance.

i. For closed scenes, shaves time off the already quick clearance time of 

other total station instruments by cutting out the need to find and focus on 

areas of interest through scope.

ii. Set up can be heavily dependent on the individual operator's expertise in 

using it. For those properly trained, set up is not time-consuming and 

subsequent measurements can be taken quickly (and with more precision 

and accuracy) than the roller wheel or tape methods.

iii. Captures scene detail required for diagrams and reconstruction analysis.

iv. Reduces time necessary to set up and take down, as well as reduced time 

to measure; all reducing time to return to a normal traffic pattern.
Crash Investigation and Reconstruction 66 U.S. Department of Transportation

Technologies and Best Practices Federal Highway Administration

c. Prompt, Reliable Communications.

i. Data is easy to share.

ii. Information can be shared with anyone who has a compatible program 

that will communicate with the total station.

iii. Data collection and sharing is mostly flawless. The data formats are 

usually compatible with most of the diagramming programs used in the 

industry.

iv. Information constantly reviewed and analyzed for building safer roads and 

traffic patterns as well as adjusting law enforcement activities in those 

areas.

6. Imaging Station.

a. Responder Safety.

i. Less risk and exposure to traffic than mechanical and electronic total 

station. User can set up in a safe area and avoid traffic.

ii. Reduces risk to investigators, reduces on-scene crash investigation.

iii. Reduces on-scene crash investigation time.

b. Safe Quick Clearance.

i. For closed scenes, shaves time off the already quick clearance time of 

other total station instruments by cutting out the need to find and focus on 

areas of interest through scope.

ii. Set up can be heavily dependent on the individual operator's expertise in 

using it. For those properly trained, set up is not time-consuming and 

subsequent measurements can be taken quickly and with more precision 

and accuracy than the roller wheel or tape methods.

iii. Captures scene detail required for diagrams and reconstruction analysis.

iv. Reduces time necessary to set up and take down, as well as reduced time 

to measure; all reducing time to return to a normal traffic pattern.

c. Prompt, Reliable Communications.

i. Data is easy to share.

ii. Data collection and sharing is mostly flawless. The data formats are 

usually compatible with most of the diagramming programs used in the 

industry.

iii. Information constantly reviewed and analyzed for building safer roads and 

traffic patterns as well as adjusting law enforcement activities in those 

areas.

iv. Provides for vast amounts of data which can be analyzed in the future.

7. Photogrammetry.

a. Responder Safety.

i. Scene can be mapped quickly.

ii. Reduces risk to investigators; reduces on-scene crash investigation time.
Crash Investigation and Reconstruction 67 U.S. Department of Transportation

Technologies and Best Practices Federal Highway Administration

b. Safe Quick Clear.

i. One of the fastest methods to create an accurate diagram, thus greatly 

accelerates clearance times.

ii. Measurements and photographs in one step.

c. Prompt, Reliable Communications.

i. Output easily imported into diagramming software packages.

ii. Information extracted at a later time.

8. 3-D Laser Scanning.

a. Responder Safety.

i. Reduces risk to investigators; reduces on-scene crash investigation time.

ii. Allows the user to scan at a distance, out of harm’s way.

iii. Need roadway closed if moderate to heavy traffic.

b. Safe Quick Clearance.

i. Takes longer to scan scenes if detail (no gaps) is desired. Enormous scene 

detail and topography information captured. Sometimes low contrast 

evidence is not clearly captured.

ii. Allows a lot of data to be collected in a short period of time. Movements 

of the instrument for viewpoints sometimes increases time needed.

c. Prompt, Reliable Communications.

i. Collects vast amounts of data which could be used for various study 

purposes in the future.

ii. Software is often proprietary and doesn't work well with other programs. 

The technology is constantly improving.

9. GPS Systems.

a. Responder Safety.

i. Has positive and negative attributes regarding Responder Safety. Easily 

used as a one-person unit; however that person can become unaware of the 

hazards around them when their full attention is given to the operation of 

the unit. It greatly reduces the time spent on-scene collecting data over 

the Reflectorless and Robotic Total Stations.

ii. Reduces on-scene crash investigation time.

b. Safe Quick Clearance.

i. Set up time is low; scenes cleared more quickly.

ii. Increases speed of data collection, clearing the scene faster. 
Crash Investigation and Reconstruction 68 U.S. Department of Transportation

Technologies and Best Practices Federal Highway Administration

c. Prompt, Reliable Communications.

i. Communications are not possible with satellites in some situations such as 

buildings, terrain, and foliage blocking sight line to satellites. There are 

places it cannot be used due to the line of sight obstructions.

ii. Information gathered is the same as the Total Stations and therefore has 

the same ease and restriction on the sharing of the data.

10. LiDAR Systems.

a. Responder Safety.

i. Allows for roadway mapping without being in traffic.

ii. Allows for measurements across/away from moving traffic, reducing 

possible exposure.

b. Safe Quick Clearance.

i. Clearance rates decrease for simple scenes. Clearance rates increase for 

complex scenes.

ii. Can improve clearance times since some of the evidence can be measured

after the roadway is open to traffic.

c. Prompt, Reliable Communications.

i. Allows for very accurate measurements which support detailed reports. 

ii. Information can be shared with anyone who has compatible software.

11. Electronic Total Station.

a. Responder Safety.

i. Reduces exposure to traffic when compared to manual measurement.

ii. Requires some exposure to traffic for prism pole operator.

iii. Reduces risk to investigators; reduces on-scene crash investigation time.

b. Safe, Quick Clearance.

i. Set up can be heavily dependent on the individual operator's expertise in 

using it. For those properly trained, set up is not time-consuming and 

subsequent measurements can be taken quickly and with more precision 

and accuracy than the roller wheel or tape methods.

c. Prompt, Reliable Communications.

i. Very easy to share data.

ii. Data typically stored in a format that is easily shared between parties but 

somewhat dependent on the knowledge of the individual storing the data. 

An individual not properly trained could produce a nearly indecipherable 

data file.
Crash Investigation and Reconstruction 69 U.S. Department of Transportation

Technologies and Best Practices Federal Highway Administration

12. Mechanical Measurement Tools.

a. Responder Safety.

i. Requires personnel close to road and roadway evidence to take 

measurements.

ii. Increases exposure of personnel to dangers of traffic.

b. Safe Quick Clearance.

i. Takes a longer period of time to make each measurement, cannot gather as 

many measurements as other methods.

ii. Takes longer and is less accurate. The value of prosecutorial information 

depends on accuracy needed but is generally lower than other options 

available.

c. Prompt, Reliable Communications.

i. Information cannot be shared easily unless it is stored in a computer 

program for later use.

ii. Reliable, but slow and prone to error.

COURT ACCEPTANCE

Ranking in order:

1. Mechanical Measurement Tools.

• Ranked high in court acceptability. Historically sound process.

2. Electronic Total Station.

• Evaluating experts rated at the highest rating for court acceptability.

3. Reflectorless Electronic Total Station.

• Evaluating experts rated at the highest rating for court acceptability.

4. Semi-Robotic Total Station.

• Evaluating experts rated at the highest rating for court acceptability.

5. Robotic Total Station.

• Evaluating experts rated at the highest rating for court acceptability.

6. Total Station Hybrid.

• Evaluating experts stated that it is accepted in court proceedings.

7. Photogrammetry.

• Evaluating experts rated at very high for court acceptability.

8. LiDAR Systems.

• Evaluating experts stated that it is accepted in court proceedings.

9. 3-D Laser Scanning.

• Evaluating experts rated at very high for court acceptability.
Crash Investigation and Reconstruction 70 U.S. Department of Transportation

Technologies and Best Practices Federal Highway Administration

10. GPS Systems.

• Evaluating experts rated at very high for court acceptability.

11. Imaging Station.

• Not rated as highly for court acceptability due to the limited use to date.

12. Unmanned Aerial Systems.

• Not rated as highly for court acceptability due to the limited use to date.

COST

Ranking in order:

1. Mechanical Measurement Tools.

2. Photogrammetry.

3. LiDAR Systems.

4. Electronic Total Station.

5. Reflectorless Total Station.

6. GPS Systems.

7. Semi-Robotic Total Station.

8. Robotic Total Station.

9. Imaging Station.

10. Total Station Hybrid.

11. 3-D Laser Scanning.

12. Unmanned Aerial Devices.
Crash Investigation and Reconstruction 71 U.S. Department of Transportation

Technologies and Best Practices Federal Highway Administration

BIBLIOGRAPHY

Texas A&M Transportation Institute. (August 2015). 2015 Urban Mobility Scorecard. College 

Station: Texas A&M Transportation Institute.
U.S. Department of Transportation

Federal Highway Administration

Office of Operations

1200 New Jersey Avenue, SE

Washington, DC 20590

www.fhwa.dot.gov

October 2015

FHWA-HOP-16-009