Alcohol availability and alcohol-related casualties in Michigan 1968-1976.

In summary alcohol availability changed throughout the 1969--1976 time period with a particularly major change caused by the 18-year-old legal drinking age (1972) and increases in the numbers and hours-of-operation of on-premise consumption establishments. Eighteen to 20-year-olds experienced increases of at least 4600 additonal traffic crashes associated with alcohol of which at least 89 involved one or more fatalities in the 1972-1975 time period. Associated with the increase in crash involvement, draught beer consumption in Michigan dramatically increased. In the absence of any convincing explanations to the contrary, we consider these conservative analyses to be compelling evidence of the role of alcohol availability in the social etiology of alcohol-related traffic casualties.