Abstract
This paper describes the impact on the incidence of driving after drinking following an intensive police DWI (driving while intoxicated) enforcement campaign in British Columbia. Police roadchecks for drinking drivers were conducted for several nights every week by the police departments in all communities involved in the program. These roadchecks were supplemented by a media campaign to help raise the perceived probability of arrest for driving after drinking. The enforcement campaign was continued in subsequent years. The purpose of these surveys was to determine the extent of change in the prevalence of night-time driving after drinking among motorists during the intervening five months of the campaign.