Research Studies & Reports
DMV’s Research & Development Branch has been conducting research and producing studies and reports since the 1950s. Research & Development reports help DMV to measure the impact of new laws on making drivers safer. We also identify areas where we can improve our processes, explore new approaches to solving existing problems, and branch out into new opportunities to serve you better.
Studies & Reports Sections
Studies and reports are assigned to a Section that best describes the type of report. Click on a section title below to see a short description.
I. Driver Education & Training Studies
II. Driver Licensing Screening Studies
III. Studies on Improvement and Control of Deviant Drivers
IV. Basic Research & Methodological Studies: Driver Performance, Accident Etiology, Prediction Models, and Actuarial Applications
V. Driver Licensing / Control Systems & Safety Management Studies
VI. Studies on Special Driver Populations
VII. Miscellaneous Studies & Reports
Request printed copies of studies and reports by mail at:
Department of Motor Vehicles
Research and Development Branch
2415 1st Ave. Mail Station: F-126
Sacramento, CA 95818
(916) 914-8125
Please include the report number, the number of copies requested, and your name, address, and phone number.
| Report ID | Date Published | Title | Section | Links |
|---|---|---|---|---|
| 258 | 2021/ 08 |
AB 2499: A Traffic Safety Evaluation of California’s Traffic Violator School Masked Conviction ProgramThe negative traffic safety impact of California’s prior traffic violator school (TVS) citation dismissal policy is well documented in past departmental TVS evaluations. Using advanced inferential statistical techniques, the current study evaluated the substantive changes to California’s Traffic Violator School program as required by California Assembly Bill 2499 (Chapter 599, Statutes of 2010). The program changes implemented by AB 2499 appear to be associated with a specific deterrent effect as evidenced by a reliable and statistically significant reduction in subsequent traffic crashes and convictions of those receiving a masked TVS conviction as opposed to a countable conviction. Although the results suggest that this relationship exists primarily among TVS drivers with less elevated prior records, the change in status from a TVS citation dismissal to a TVS masked conviction has reduced the negative traffic safety impact of the TVS citation dismissal policy in effect prior to the implementation of AB 2499. Several recommendations are offered to enhance the positive traffic safety impact of the TVS program by further combining its educational elements with the Department’s post-license control program by way of the Negligent Operator Treatment System. |
III | |
| 251 | 2016/ 06 |
AB 91: Specific Deterrent Evaluation of the Ignition Interlock Pilot Program in CaliforniaThis study presents an evaluation of the specific deterrence effects of California’s ignition interlock pilot program mandated by AB 91 to operate in four California counties — Alameda, Los Angeles, Sacramento, and Tulare — from July 1, 2010 to January 1, 2016. This study is a follow-up to an earlier legislatively-mandated general deterrence evaluation of AB 91’s IID pilot program. The purpose of the present study is to evaluate the specific deterrent capacity of AB 91’s IID pilot program, that is, whether it led to reductions in DUI recidivism and crashes among DUI offenders. Results show that, while the AB 91 pilot program can be associated with reductions in DUI recidivism among specific DUI offender groups, it is also associated with an increase in subsequent crashes among all first DUI offenders in AB 91 pilot counties and among all DUI offenders who installed an IID and obtained an AB 91 IID-restricted driver license. Although the reduction in DUI recidivism provides evidence of benefits associated with IID restrictions, the increased crash risks associated with the AB 91 pilot program suggest that additional investigation and research could be beneficial. Inclusion of information regarding crash responsibility (i.e. at-fault/not-at-fault), alcohol involvement, or severity level (i.e. fatal/injury crashes vs property-damage only crashes) may provide further insight. The report recommends to (1) evaluate California's incentive IID program mandated under Senate Bill 598, (2) conduct and report to the Legislature a quantitative evaluation of the efficacy of current or potential DUI countermeasures (including IIDs) and their combined use, (3) explore the option of using IIDs as an “alcohol-abstinence-compliance” monitoring tool, as part of a modified version of the traditional DUI court model, and (4) convene a task force to develop recommendations for strengthening components of California's comprehensive DUI countermeasure system. |
V | |
| 111 | 1987/ 01 |
Accident and Conviction Rates of Visually Impaired Heavy Vehicle OperatorsThis study was designed to determine whether waiving the federal static acuity standard adversely impacted traffic safety. Drivers for whom the standard was waived could drive commercially only within California. Two-year accident and conviction rates of visually impaired commercial heavyvehicle operators (class 1 or 2 licensees) were compared to those of a sample of visually nonimpaired commercial heavy-vehicle operators. Nonimpaired drivers met current federal acuity standards (corrected acuity of 20/40 or better in both eyes), while impaired drivers had substandard static acuity and were classified as either moderately (corrected acuity between 20/40 and 20/200 in the worse eye) or severely (corrected acuity worse than 20/200 in the worse eye) impaired. California and total mileage estimates for Class 1 and Class 2 drivers obtained in a mailed questionnaire did not differ significantly between impairment groups. However, other potentially biasing factors remained and are discussed. Analysis of covariance, with age as a covariate, revealed that on subsequent two-year driver records the visually impaired drivers had significantly, and substantially, more total accidents and convictions than did the nonimpaired drivers. Severely impaired drivers had directionally worse driver records than did the moderately impaired drivers on three of the four traffic safety measures assessed, but these differences were not statistically significant. Study findings led to qualified support for the stricter federal standard, particularly in the case of the severely impaired heavy-vehicle operator. |
VI | |
| NRN031 | 1986/ 06 |
Accident Rates, Financial Responsibility, and Restriction Compliance of SB-38 ParticipantsTo collect data regarding the accident rates, financial responsibility, and restriction compliance of SB-38 alcohol treatment program participants, in response to a legislative proposal requiring proof of financial responsibility for SB-38 program participants. |
III | |
| NRN104 | 1991/ 01 |
Accidents, Mileage, and the Exaggeration of RiskTo correct a common misinterpretation of the accidents-per-mile measure. The assumption that accidents should be proportional to miles driven is shown to be invalid and to exaggerate the accident risk of lowmileage groups. |
VII | |
| NRN070 | 1976/ 04 |
Administrative Adjudication of Traffic Offenses in California: A Feasibility StudyTo comply with Senate Concurrent Resolution 40 (1975 Resolution Chapter 86), which mandated a feasibility study of administrative adjudication of traffic infractions. |
V | |
| 175 | 1998/ 07 |
Administrative Per Se (APS) Set Aside Process AnalysisEach year, something less than three quarters of drivers arrested for driving under the influence (DUI) in California are actually convicted of the offense, and often only after long delays following their arrest. |
V | |
| 156 | 1994/ 07 |
AGE-RELATED DISABILITIES THAT MAY IMPAIR DRIVING AND THEIR ASSESSMENTThis review, covering literature on age-related disabilities, their assessment, and their effects on driving, represents the initial step in developing an assessment system for identifying and evaluating the driving competency of older drivers with dementia or age-related frailty. Since frailty can be defined as a result of the combined effect of various pathologies superimposed upon the normal physiological changes of aging, emphasis is given to medical conditions which are more characteristic of elderly people. The relationships of these conditions to driving performance and safety are discussed, and nondriving and driving tests relevant to identifying and licensing frail or dementing elderly are described. There is a brief discussion of licensing and post-licensing control programs for elderly drivers in several jurisdictions, including graded licensing. A preliminary assessment protocol for identifying medically impaired elderly drivers and evaluating their driving ability is suggested. |
VI | |
| 46.1 | 1974/ 01 |
An abstract of An Evaluation of California’s “Good Driver” Incentive ProgramTo study the effects of rewards and/ or incentives in the form of one-year license extensions (no testing or visit to field office required) for drivers with one-year-clean prior records. |
II | |
| 70.1 | 1979/ 07 |
An Abstract of An Evaluation of Probation-by-Mail as an Alternative to Mandatory Hearing Attendance for Negligent OperatorsTo evaluate the feasibility and traffic safety implications of placing negligent operators on probation by letter without the subjects being scheduled for a hearing. |
III |