This study assesses the impact of enforcing laws against driving while impaired (DWI) on fatal accident rates in Québec (Canada) between 1980 and 2003. Rather than using traditional interrupted time series, fatal accident rates are regressed on respective indicators of the probability of being arrested for DWI, the likelihood of being incarcerated for DWI and media campaigns. The findings of this study demonstrate that the increase in the probability of being incarcerated and the introduction of the media campaigns in December 1985 resulted in a decrease in fatal accident rates. According to the regression coefficients, the rise in incarceration risks prevented about 1,390 fatal accidents between 1980 and 2003 while media campaigns are associated with a reduction of 919 in night time fatal accidents between 1986 and 2003. (Author/publisher)
Abstract