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
254 2017/ 07

Predicting Traffic Crash Involvement Using Individual Driving Habits, Driving Record, and Territorial Risk Indices

By: Michael A. Gebers, Jeff Moulton

This study surveyed a sample of California drivers to determine their habits and opinions on selected traffic issues. The study also assessed the importance of exposure and territorial risk indices as predictors of traffic crashes beyond that of driver record factors. The information provided in this report is intended to assist traffic safety administrators and lawmakers in improving services and in developing more effective driver safety programs.

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255 2018/ 06

An Evaluation of The Effect of Gaps In Licensure On Traffic Safety Outcomes Subsequent to Renewal

By: Kevin Limrick

Absent a progressive physical or mental condition, motorists in California are permitted to renew their driver license without submitting to a skills test. This policy applies regardless of how long a customer’s license has been expired. Given a lack of published research on the retention of motor skills required of driving, the current study was designed to evaluate the effect of a “gap” in licensure on one’s ability to safely operate a motor vehicle. More specifically, it sought to determine whether a gap in a customer’s licensing history was associated with crashes and / or convictions subsequent to renewal. To that end, the Department’s Driver License Master File was used to identify motorists in California who had a clearly defined gap at some point during their licensing history. These customers were then placed into one of three study groups based upon the length of time it took for them to relicense: 1 to 30 days (n = 6,135), 31 to 365 days (n = 4,688), or greater than 365 days (n = 1,973). A fourth group of drivers, all of whom had not experienced a gap in their licensing history (i.e., those who renewed early), was also identified to serve as a type of quasi-experimental control group. These analyses found that drivers who had a gap of at least 1 year had the same odds of incurring at least one post-renewal conviction as did drivers who renewed early. Logistic regression and Cox proportional hazards models also indicated that gap duration was not a significant predictor of post-renewal crash involvement; drivers in this study were equally likely to experience a post-renewal crash, regardless of how long they were unlicensed. Based on the findings of this report, recommendations are made to maintain current DMV policy and not integrate skills testing as part of the renewal process, absent additional information indicating potential issues of concern (e.g., a progressive vision disorder).

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256 2018/ 10

2016 Annual Report of the California DUI Management Information System

By: Helen N. Tashima, Sladjana Oulad Daoud

In this twenty-fifth annual legislatively-mandated report, 2013 and 2014 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, court sanctions, license suspension/revocation actions, and 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 24 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 DUI incidents 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 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 2013, who were referred, enrolled, and completed DUI programs are also presented.

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257 2018/ 10

2017 Annual Report of the California DUI Management Information System

By: Sladjana Oulad Daoud, Helen N. Tashima

In this twenty-sixth annual legislatively-mandated report, 2014 and 2015 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 25 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 2014, 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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259 2020/ 01

2018 Annual Report of the California DUI Management Information System

By: Sladjana Oulad Daoud, Helen N. Tashima

In 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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NRN024, NRN025, NRN026, NRN027, NRN028, NRN029, NRN030 2020/ 04

Post Licensing Control Reporting and Evaluation System (PLCRES): Negligent Operator Program Costs and Effectiveness

By: Daniel Kadell, William Howe, John Magistad, Ph.D., Raymond C. Peck, William Epperson, Steve Fong, William C. Marsh, David W. Carpenter, Philip Wootton

To implement and maintain an automated on-line evaluation system tor monitoring the effectiveness of negligent-operator programs.

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102 110 115 117 128 137 2020/ 04

Negligent-Operator Treatment Evaluation System (NOTES): Program Effectiveness Reports

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119 125 130 136 140 2020/ 04

Annual Tabulations of Mature Driver Program Driving Record Comparisons (1989-1993). Annual Report to the Legislature of the State of California.

By: Lee Stylos, Mary K. Janke, Eric Berube, Robert A. Hagge, Kevin K. Foster

To provide annual tabulations comparing the accident and conviction records of Mature Driver Improvement (MDI) course participants and of a randomly selected group of drivers of similar age (55 and above).

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260 2020/ 06

2019 Annual Report of the California DUI Management Information System

By: Oulad Daoud, Tashima

In this twenty-eighth annual legislatively-mandated report, 2016 and 2017 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.

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261 2021/ 07

2020 Annual Report of the California DUI Management Information System

By: Sladjana Oulad Daoud

In this twenty-ninth annual legislatively-mandated report, 2017 and 2018 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 in each year over a time period of 28 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 2017, 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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