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. 

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.

393 Results

Report ID Date Published Title Section Links
111 1987/ 01

Accident and Conviction Rates of Visually Impaired Heavy Vehicle Operators

By: Patrice N. Rogers, Michael Ratz, and Mary K. Janke

This 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.

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251 2016/ 06

AB 91: Specific Deterrent Evaluation of the Ignition Interlock Pilot Program in California

By: Research and Development Branch

This 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.

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258 2021/ 08

AB 2499: A Traffic Safety Evaluation of California’s Traffic Violator School Masked Conviction Program

By: Michael A. Gebers, Bayliss J. Camp

The 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
223 2007/ 04

A Traffic Safety Evaluation of California’s Traffic Violator School Citation Dismissal Policy

By: Michael A. Gebers

This study applied methodological refinements to the 1991 departmental evaluation of the traffic violator school (TVS) citation dismissal policy. This study identified and compared two large samples of drivers either completing a TVS (N = 210,015) or convicted of a traffic citation (N = 168,563). Prior to adjudication, the TVS group had characteristics (e.g., lower prior conviction rate and smaller proportion of males) that were predictive of a lower subsequent crash risk. However, the TVS group exhibited significantly more crashes than did the convicted group in the subsequent one-year period. The difference (4.83%) increased to 10% after adjusting for the more favorable characteristics of the TVS group. The TVS group also had a higher adjusted subsequent crash rate at each prior driver record entry level, reflecting a loss in the general and specific deterrence of the non-conviction masked status of TVS dismissed citations. It was also demonstrated that approximately 15,000 Negligent Operator Treatment System (NOTS) Level 3 (probation/suspension hearings) and 6,000 NOTS Level 4 (probation violator sanctions) interventions are circumvented annually because of TVS dismissals. The demonstrated effectiveness of the NOTS interventions in reducing crash risk of treated drivers assists in explaining why the driving public is exposed to an increased crash risk as a result of their avoidance. A number of recommendations are offered to reduce the negative traffic safety impact of the TVS citation dismissal policy.

III
123 1989/ 12

A Time Series Evaluation of the General Deterrent Effects of California’s 1982 DUI Legislative Reforms (Volume 2 of “Development of a DUI Recidivism Tracking System”)

By: Patrice N. Rogers & Steve E. Schoenig

To evaluate the effect of a series of 1982 DUI legislative reforms in deterring drunk driving, as measured by the impact on alcohol-related fatal or injury accident rates.

III
NRN019 1977/ 02

A Study on the Feasibility of Placing Selected Negligent Operators on Probation by Mail

By: Beverly R. Sherman & William V. Epperson

To estimate the potential cost savings if negligent operators had the option of waiving the hearing process and accepting probationary status by mail.

III
6 1960/ 08

A Study of Parking DMV Headquarters Area 1963-1970-1980

By: Research & Development

To study and report on the parking and traffic schemes of the Department of Motor Vehicles Headquarters Building in Sacramento, in response to the City of Sacramento Inter-Governmental Committee (Councilman Philip Mering, chairman).

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7 1960/ 10

A Study of Mechanization of Operations – Drivers License Information Request Services

By: Research & Development

To study, at the request of Mr. Fred P. Williams, Chief, Division of Drivers Licenses, the systems applicable to the mechanization of the sorting and billing operations in the Department of Motor Vehicle’s Information Request Unit.

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4 1960/ 02

A Study of Information Requests Services

By: Research & Development

To determine areas of organization policy and procedure, relating to the registration of vehicles and such information as is contained on an application for a drivers license, where improvements are applicable and recommend corrective action.

VII
NRN091 1984/ 07

A Study of Alternative Strategies for Assessing Fees on Commercially Registered Vehicles

By: California Department of Motor Vehicles

This study was initiated by the Division of Registration and Investigative Services. The scope of the study was subsequently broadened to meet the requirements of Senate Concurrent Resolution (SCR) 11 of the 1983 legislative session. The final report for this study was submitted in July 1984. The objectives of this study were to: 1. develop a schedule for assessing weight fees on commercially registered power vehicles (6,500 or more pounds unladen) and trailers, based on declared laden or gross weight (GVW) of individual power vehicles and trailers (this schedule would replace the current unladen weight fee table; registration and vehicle license fees would continue to be collected); 2. develop a fee-assessment system for commercially registered power vehicles (6,500 or more pounds unladen) and trailers, based on the declared combined gross weight (CGW) of power vehicles (CGW would be declared for only power units and would include the total weight of the power unit, all trailing vehicles, if any, and all loads) and charging only a standard fee on each trailer (the CGW fee assessed on power vehicles and the trailer fee would replace the registration, vehicle license, and unladen weight fees currently collected on power vehicles and trailers); and 3. estimate the total 1985 revenue loss under a CGW fee schedule that would allow fees remaining on deleted interstate power vehicles to be credited toward fees due on their power vehicle replacements, and produce an adjusted CGW fee schedule that would recoup this revenue loss.

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