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
Note Please include the report number, the number of copies requested, and your name, address, and phone number.
| Report ID | Date Published | Title | Section | Links |
|---|---|---|---|---|
| NRN071 | 1989/ 01 |
Elderly Driver InterventionsRaymond C. Peck |
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| 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. |
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| 249 | 2014/ 10 |
Evaluation of Law Enforcement Use of Driver License Card Readers to Improve Detection of Suspended and Revoked Drivers at DUI/License CheckpointsIntroduction. Driving privilege suspension and revocation are known to improve traffic safety, but research suggests the majority of suspended or revoked (SR) drivers continue to drive while they are SR. These drivers are about three times more likely to be involved in crashes and to cause a fatal crash. In most U.S. states, drivers arrested for driving under the influence of alcohol or drugs (DUI) are subject to immediate driver license (DL) card confiscation by law enforcement. Drivers SR for other reasons are typically mailed notices directing them to surrender their DL cards to the licensing agency, yet they frequently do not comply. At DUI checkpoints in California, and many other U.S. states, law enforcement officers briefly inspect drivers’ DL cards and check for signs of intoxication. Hence, such checkpoints are deemed DUI/License status checkpoints. Previous research found that about 41% of SR drivers contacted at such checkpoints avoided detection for SR driving because they illegally retained possession of their DL cards. In this study, DL card readers with the capacity to identify and alert officers to drivers with SR statuses were used at the checkpoints. The purpose was to evaluate the utility of implementing this type of technology on a broader scale. Method. Checkpoint police officers used DL card readers that contained lists of SR drivers that would alert if a card was scanned that matched a DL number on the list. Data for 13,530 drivers were recorded. Subsequently, license statuses of contacted drivers were verified and compared to checkpoint citation records. Results. About 3% (n=384) of drivers contacted at the checkpoints were SR. Seventy-one percent of them were detected and cited for driving while SR. There were no differences in detection rate as a function of the suspension/revocation reasons. Significant differences were found in detection rate as a function of whether drivers’ DL numbers were on the SR list. Conclusion. SR drivers’ ability to pass undetected through DUI/License checkpoints weakens both the specific and general SR driving deterrence of checkpoints, and may diminish the effectiveness of suspension and revocation for reducing the crash risk posed by problem drivers. These findings show that despite technical limitations, a list-based DL card reader can improve the detection rate of SR drivers by law enforcement. Future studies that evaluate scanning technologies capable of real-time license validity verification are warranted. |
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| 259 | 2020/ 01 |
2018 Annual Report of the California DUI Management Information SystemIn this twenty-seventh annual legislatively-mandated report, 2015 and 2016 driving under the influence of alcohol and/or drugs (DUI) data from diverse sources were compiled and cross-referenced for the purpose of developing a single comprehensive DUI data reference and monitoring system. This report presents crosstabulated information on DUI arrests, convictions, postconviction sanctions, driver license suspension/revocation actions, and on drivers in alcohol-or drug-involved crashes. In addition, this report provides 1-year proportions of DUI recidivism and crash rates for first and second DUI offenders arrested in each year over a time period of 26 years. Also, the long-term recidivism curves of the cumulative proportions of DUI reoffenses are shown for all DUI offenders arrested in 2005. An analysis was conducted to evaluate if referrals to the 9-month DUI program were associated with reductions in 1-year subsequent DUI incidents and crashes when compared to referrals to the 3- month DUI program among first DUI offenders. The proportions of convicted first and second DUI offenders arrested in 2015, who were referred, enrolled, and completed DUI programs are also presented. Additionally, the numbers and percentages of DUI offenders who installed ignition interlock devices are presented by county and DUI offender status. |
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| 250 | 2015/ 01 |
2015 Annual Report of the California DUI Management Information SystemIn this twenty-fourth annual legislatively-mandated report, 2012 and 2013 driving under the influence of alcohol and/or drugs (DUI) data from diverse sources were compiled and cross-referenced for the purpose of developing a single comprehensive DUI data reference and monitoring system. This report presents crosstabulated information on DUI arrests, convictions, court sanctions, administrative actions, and alcohol- or druginvolved crashes. In addition, this report provides 1-year proportions of DUI recidivism and crash rates for first and second DUI offenders arrested in each year over a time period of 23 years. Also, the long-term recidivism curves of the cumulative proportions of DUI reoffenses are shown for all DUI offenders arrested in 1994. Two analyses were conducted to evaluate if referrals to DUI programs were associated with reductions in 1-year subsequent violations and crashes among those convicted of the reduced charge of alcohol- or drug-related reckless driving, and if referrals to the 9-month DUI program were associated with reductions in 1-year subsequent violations and crashes when compared to referrals to the 3-month DUI program among first DUI offenders. The proportions of convicted first and second DUI offenders arrested in 2012, who were referred, enrolled, and completed DUI programs are also presented. |
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| 263 | 2023/ 04 |
2022 Annual Report of the California DUI Management Information SystemIn this thirty-first annual legislatively mandated report, 2019 and 2020 driving under the influence of alcohol and/or drugs (DUI) data from diverse sources were compiled and cross-referenced for the purpose of developing a single comprehensive DUI data reference and monitoring system. This report presents cross-tabulated information on DUI arrests, convictions, postconviction sanctions, driver license suspension/revocation actions, and on drivers in alcohol- or drug-involved crashes. In addition, this report provides 1-year proportions of DUI recidivism and crash rates for first and second DUI offenders arrested each year over a period of 30 years. Also, the long-term recidivism curves for the cumulative proportions of DUI reoffenses are shown for all DUI offenders arrested in 2005. The proportions of convicted first and second DUI offenders arrested in 2019 who were referred to, enrolled in, and completed DUI programs are also presented. Additionally, the numbers and percentages of DUI offenders who installed ignition interlock devices are presented by county and DUI offender status. |
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| 210 | 2004/ 09 |
AN EVALUATION OF THE EFFECTIVENESS OF IGNITION INTERLOCK IN CALIFORNIAThis study is one of two studies of ignition interlock in California mandated by the California Legislature (AB 762). The first study, published in 2002, was a process evaluation that examined the degree to which ignition interlock has been implemented in California. This current study is an outcome evaluation that examines the effectiveness of ignition interlock in reducing alcohol-related crashes and convictions, and crashes overall (alcohol and nonalcohol). The results of the study show that interlock works for some offenders in some contexts, but not for all offenders in all situations. More specifically, ignition interlock devices work best when they are installed, although there is also some evidence that judicial orders to install an interlock are effective for repeat DUI offenders, even when not all offenders comply and install a device. California’s administrative program, where repeat DUI offenders install an interlock device in order to obtain restricted driving privileges, is also associated with reductions in subsequent DUI incidents. One group for whom ignition interlock orders do not appear effective is first DUI offenders with high blood alcohol levels. |
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| 134 | 1992/ 01 |
1992 Annual Report of the California DUI Management Information SystemTo start the publication of a yearly comprehensive data and monitoring system (or management information system) to provide measures of DUI system performance. |
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| 145 | 1995/ 01 |
1995 ANNUAL REPORT OF THE CALIFORNIA DUI MANAGEMENT INFORMATION SYSTEMIn this fourth annual report, 1992 and 1993 DUI data from several diverse sources were compiled and cross-referenced for the purpose of developing a single comprehensive DUI data and monitoring system. This report presents crosstabulated information on DUI arrests, convictions, court sanctions, administrative actions and alcohol-involved accidents. In addition, this report provides an evaluation of the effectiveness of alternative court and administrative sanctions (including alcohol treatment programs and license actions) upon the postconviction records of first and second DUI offenders. The postconviction driving records of DUI offenders arrested in 1989, 1991, and 1992 were evaluated for four-, two-, and one-year periods, respectively. |
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| 162 | 1996/ 05 |
Predicting DUI Recidivism. Volume 1: Blood Alcohol Concentration and Driver Record FactorsThis study examined the relationship between BAC at arrest, driving history, and other demographic factors, and the 1-year post-arrest probability of recidivism for DUI convictees. BAC-only prediction models, complex prediction models involving many factors found on the driver record, and simple prediction models containing two or three factors were developed. All models found a third degree or cubic relationship between BAC and recidivism, and showed recidivism to be high at a BAC of 0.00%, decreasing down to a BAC of about 0.09%, increasing to a BAC of about 0.29%, and then decreasing again to a BAC of 0.35%+. High rates of recidivism at high BACs suggest alcohol dependency, while at low BACs other impairing substances are likely to be involved. The mean rate of DUI recidivism for offenders who refused to be tested for alcohol was the same as the mean rate for BAC-tested offenders who had prior DUIs at the time of the arrest. |
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