Over the past 30 years, roadside surveys of drivers in Canada have been a vital source of information contributing to the understanding of alcohol-impaired driving. Since 1995, periodic surveys have been conducted in British Columbia helping to determine the incidence and characteristics of drinking and driving over time.
Objective information about the use of drugs by drivers has been more difficult to obtain. While alcohol can be measured easily through roadside breath samples, drug testing requires a more complex laboratory test on bodily fluid samples. In recent years, oral fluid has emerged as a convenient, non-invasive means to gather evidence on drug use among drivers.
The B.C. Roadside Survey 2008: Alcohol and Drugs Use Among Drivers was conducted at randomly selected locations in British Columbia from Wednesday to Saturday nights in June 2008. The purpose was to measure the use of alcohol and drugs among nighttime drivers. Of the 1,533 vehicles selected, 89% of drivers provided a breath sample and 78% provided an oral fluid sample. It was found that 10.4% of drivers tested positive for drug use and 8.1% of drivers had been drinking. Overall, 15.5% of drivers tested positive for alcohol, drugs or both. Cannabis and cocaine were the drugs most frequently detected. It appears that drug use and alcohol use have different patterns of use. (Characteristics of the sample and of the drivers are discussed in the report). Whereas alcohol use among drivers was most common on weekends and during late-night hours, drug use was more evenly distributed across all survey nights and times. Alcohol use was most common among drivers aged 19 to 24 and 25 to 34; drug use was more evenly distributed across all groups.
The results shed light on the magnitude of the problem, providing a basis for guiding the development of prevention efforts and helping enforcement agencies to deal effectively with drug-impaired driving behaviour. The survey established a benchmark from which to assess the impact of the new drugs-and-driving legislation and the implementation of the Drug Evaluation and Classification (DEC) program. The survey also measured the prevalence of alcohol use among drivers, providing new information on drinking and driving trends. It highlights the need for a societal response to the use of drugs by drivers comparable to that directed at drinking and driving over the past three decades.
The complete report, the B.C. Roadside Survey 2008: Alcohol and Drugs Use Among Drivers, as well as a Report in Short—Drugs and Driving are available by clicking on the link at the right side of this page.