Fatally Injured Drivers Testing Positive for Marijuana on the Rise

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Ottawa, December 4, 2017 – The Traffic Injury Research Foundation (TIRF) is pleased to announce the release of a new fact sheet that summarizes trends in marijuana use among fatally injured drivers in Canada between 2000 and 2014. Results show that, since 2000, the percentage of fatally injured drivers testing positive for marijuana increased, while during this same time period, the percentage of fatally injured drivers testing positive for alcohol decreased. Results are based on data from TIRF’s National Fatality Database, which is maintained with financial support from State Farm® and the Public Health Agency of Canada.

According to TIRF’s National Fatality Database, in 2000, almost 35% of fatally injured drivers tested positive for alcohol compared to 12% who tested positive for marijuana. By 2014, this percentage for alcohol had declined to 28% whereas it increased to almost 19% for marijuana. Results vary greatly by age. Marijuana was the drug most commonly detected among 16-19 and 20-34 year-old fatally injured drivers (29.8% and 27.2% respectively). Fatally injured drivers in older age categories were more likely to test positive for other drug types, notably Central Nervous System (CNS) depressants (18.1% among 35-64 year-old drivers and 26.3% among drivers 65 and older).

“What we see is an increasing percentage of fatally injured drivers in Canada who tested positive for marijuana in recent years whereas the percentage who tested positive for alcohol is decreasing,” explains Dr. Woods-Fry, a research associate with TIRF. “While the percent is still higher for alcohol today, if current trends continue, marijuana might become more prevalent among fatally injured drivers.”

The data further reveal that time of day and day of the week play a lesser role in predicting the presence of marijuana among fatally injured drivers compared to alcohol. “Twenty one percent of drivers dying in weekend crashes tested positive for marijuana versus 17% in weekday crashes,” explains Robyn Robertson, President & CEO of TIRF. “In comparison, 46% of fatally injured drivers in weekend crashes tested positive for alcohol versus 26% in weekday crashes.” Similar patterns are evident for time of day with a more pronounced contrast in the presence of alcohol at night versus daytime and a less pronounced contrast in the presence of marijuana.

One way to address the issue of marijuana and driving is information sharing and education. “State Farm and TIRF recently launched a new resource, the Drug Impaired Driving Learning Centre (DIDLC), where stakeholders and the public can find the latest facts, research and information about this topic,” says John Bordignon, Media Relations spokesperson for State Farm Canada. “Increased public education is essential to bringing awareness to the issue of cannabis and prescription drug impaired driving, with the impending legalization of recreational marijuana, a resource like the DIDLC is a valuable tool that can help save lives.”

Access the Drug Impaired Driving Learning Centre (DIDLC) here:

Download Fact Sheet: Marijuana Use Among Drivers in Canada, 2000-2014 

About the Traffic Injury Research Foundation:
The mission of the Traffic Injury Research Foundation (TIRF) is to reduce traffic-related deaths and injuries. TIRF is an independent, charitable road safety research institute. Since its inception in 1964, TIRF has become internationally recognized for its accomplishments in identifying the causes of road crashes and developing programs and policies to address them effectively. 

® State Farm and related trademarks and logos are registered trademarks owned by State Farm Mutual Automobile Insurance Company, used under licence by Certas Home and Auto Insurance Company and certain of its affiliates.

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For more information, please contact:


David Bird
Website administrator for TIRF.ca

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