Effects of the increased minimum drinking age law on drinking and driving behavior among adolescents

In Minnesota, the minimum drinking age law was raised from 19 to 21, effective September 1, 1986. As anyone born prior to September 1, 1967 could legally continue to purchase alcohol, we hypo,thesized that adolescents burn on or after September 1, 1967 would report less drinking and driving than their peers born prior to this date. Participants originally comprised the entire seventh-grade enrollment of four suburban school districts in Minnesota in 1979 and 1980 (N = 7124). Drinking and driving data were collected in 1987 and 1988. Comparing the Younger cohort (born on or after September 1, 1967) in 1988 to the Older cohort in 1987, we observed lower overall drinking and driving prevalence in the Younger cohort. The Younger cohort reported a significantly lower rate of drinking after drinking at least two drinks than did the Older cohort, though there was a minimal difference in rates of heavy drinking and driving, The increased drinking age seemed effective in reducing the overall drinking and driving prevalence primarily by deterring from driving subjects who had been drinking one or only a few drinks.