Book Description

Although California's statewide driving-under-the-influence of alcohol and/or drugs (DUI) conviction rate has improved over time from 64% in 1989 to 79% in 2006, the DUI conviction rates vary considerably among counties. The purpose of this study was to identify factors associated with differences among California county DUI conviction rates averaged from 2000-2006. The three approaches to obtain information were: (a) surveys sent to California judges, prosecuting attorneys, public and private defense attorneys, and court administrators; (b) face-to-face interviews conducted with California judges, prosecuting attorneys, and public and private defense attorneys; and (c) analyses of various county-level demographic and socioeconomic factors, DUI arrest and conviction process measures, and crash/recidivism variables. It was found that counties with higher DUI arrest rates tend to have lower DUI conviction rates. Counties with high DUI conviction rates tend to convict at lower BAC levels and have higher percentage usage of blood BAC tests. Counties also varied in their alcohol-reckless conviction rates as well as the BAC levels considered appropriate for negotiating alcohol-reckless plea bargains. While the 7-year (2000-2006) statewide average percentage of DUI arrestees convicted of alcohol-reckless driving was 8.1%, county percentages ranged from 0% to 22.6%. Higher prosecution caseload as measured by county violent crime rates is associated with lower DUI conviction rates, while shorter lengths of time from arrest to conviction are associated with higher DUI conviction rates. Varying prosecution policies were strongly identified by survey respondents as influencing variation in county DUI conviction rates. Convicting for drug-only DUI was considered to be very difficult due to the lack of scientifically based per se levels of drug impairment. Recommendations are made based on these findings.