Evaluation of the effects of North Carolina's 0.08% BAC law

This study was conducted to determine whether the lowered BAC limit for dri vers in North Carolina resulted in fewer alcohol-related motor vehicle cras hes. We used time-series analysis to examine several indicators of alcohol involvement in both injury and fatal crashes between 1991 and 1996. Data fr om NC crash files as well as the Fatality Analysis Reporting System (FARS) are used. We also examined several indicators used in previous research on lower BAC limits using a before-after design to compare North Carolina with 37 states that did not change their BAC limit for 24 months before and aft er the BAC limit was lowered. When controlling for the pre-existing downwar d trend in drinking driver crashes, along with other pertinent factors such as amount of travel and number of weekends per month, there was no evidenc e of either a significant shift or a change in the downward trend of alcoho l-related crashes associated with the lowered BAC limit. In conclusion, alt hough the lower BAC limit was actively enforced and a substantial proportio n of drinkers were aware of the new BAC limit, the drinking-driving populat ion in North Carolina, at the time the lower limit took effect in October 1 993, was simply unresponsive to this change. (C) 2001 Elsevier Science Ltd. All rights reserved.