The impact of lowering the illegal BAC limit to 0.08 in five states in the US

It is illegal per se to have a certain blood alcohol concentration (BAC) while driving a motor vehicle in most states of the United States (U.S.). The majority of these states have set the illegal BAC limit at .10g/dl for drivers aged 21 and over. However, eleven states have lowered the limit to.08g/dl. An analysis was conducted using fatal crash data to determine the impact of lowering the per se limit to .08 in five of those states which had the law for at least two years. The results of the analyses revealed statistically significant reductions of driver involvement in alcohol-related fatal crashes after .08 legislation took effect in four of the five states, ranging from 4% in California to 40% in Vermont. This assessment appears to indicate that the implementation of .08 laws and other related activities (i.e. public information about the law) are associated with reductions in fatal crash driver alcohol involvement.