This research evaluates the interlock record as a predictor of future driving-under-the-influence (DUI) offenses relative to driver records and self-report items. Subjects were 2,273 DUI offenders who used an interlock to gain full reinstatement of driving privileges; for 2,134, the installed periods ranged from 5-30 mo. A median of 8.1 breath tests was logged for each installed day; 9.9 tests were taken on each day of vehicle use. Predictors of postinterlock repeat DUI were compared by sensitivity and survival analyses. Although 69% of all interlock users had at least 1 blood alcohol concentration (BAC) test >/=.04% (failure) within the first 5 mo, only 9% were reconvicted up to 4 yrs after interlock removal. Failed interlock tests proportional to all BAC tests taken was the best predictor of driver recidivism risk in the years following interlock removal. The interlock record provides new information, especially about drivers with no prior DUI offenses. Prior moving violations and driving while suspended convictions, although better predictors than questionnaire data, were poorer than interlock records and prior DUI offenses. The alcohol interlock, already recognized as a useful control device, warrants attention for DUI prediction.
Abstract