This project evaluated the impact of two new California driving-under-the-influence (DUI) laws on the subsequent alcohol-related accident and recidivism rates of apprehended DUI offenders. The first law, effective January 1, 1990, reduced the state's illegal per se blood alcohol concentration (BAC) limit to 0.08% and the second, effective just six months later, on July 1, 1990, imposed an administrative per se (APS) pre-conviction license suspension on arrested DUI offenders. Logistic regression analysis was used to evaluate the specific deterrent impact of the new laws by comparing the subsequent recidivism and alcohol-related accident rates of DUI offenders arrested before and after implementation of the new laws. The evaluation showed that the new laws were highly effective in reducing subsequent accidents and recidivism among DUI offenders, whether or not the offenders were subsequently convicted of their offence. There were significant reductions in all three of the 1-year indices of recidivism assessed (1-year subsequent total accidents, had-been-drinking accidents, and DUI convictions), with reduction magnitudes ranging between 19.5% and 37.1% from pre-law recidivism rates. The magnitude and consistency of the reductions provide compelling evidence that administrative license suspension is a highly effective means of reducing recidivism among first and repeat DUI offenders. The enactment of the 0.08% law accentuated the net deterrent effect of the APS law by increasing the number of DUI offenders who were suspended by about 3,300 per year. (Author/publisher)
Abstract