Effects of enhanced sanctions for high-BAC DWI offenders on case dispositions and rates of recidivism.

Implemented January 1, 1998, Minnesota's high-BAC law mandates more severe administrative pre-conviction penalties and more severe post-conviction penalties for offenses with BACs > or = 0.20%. Most notably, the law provides for the administrative impoundment of the license plate of first-time DWI offenders with BACs > or = 0.20. During the three years after the law took effect, a large majority of first-time and repeat offenders with BACs > or = 0.20% did, in fact, receive high-BAC administrative dispositions and/or high-BAC court convictions, which carried more severe penalties. For example, in 1998 85.6% of first offenders with BACs > or = 0.20% received a high-BAC administrative disposition and/or a high-BAC court conviction; 65.0% received both high-BAC administrative and high-BAC court dispositions. The proportion of high-BAC first-time offenders who received the statutory high-BAC dispositions declined from 1998 to 1999 and 2000. Based on survival analysis, the one-year recidivism rate among first offenders arrested in 1998 with BACs > or = 0.20% was significantly lower than for offenders with BACs 0.17-0.19% (who also had relatively high BACs but were not subject to enhanced sanctions), after controlling for age and gender. There were similar, but not significant, results for first offenders arrested in 1999.