No increase in traffic injuries after cannabis legalization: Study

Postmedia News 2 minute read December 4, 2021

Despite reports of increased impaired driving cases after recreational cannabis was legalized, a new study found pot legalization did not lead to an increase in traffic injuries in Ontario and Alberta.

The UBC study looked at close to 240,000 reports on emergency room patients from Ontario and Alberta — the only provinces documenting ER visits — between 2015 and 2019.

Researchers compared all moderate-to-severe car crash injuries to those recorded in the 14 months after cannabis legalization in 2018 and found the weekly average reports of traffic accident injuries in both provinces remained largely the same as before pot became legal.

“Our findings are somewhat surprising,” University of Northern B.C. professor Russ Callaghan said in a press release. “I predicted that legalization would increase cannabis use and cannabis-impaired driving in the population, and that this pattern would lead to increases in traffic-injury presentations to emergency departments.”

Callaghan noted that the introduction of stricter federal legislation — such as Bill C-46, which amended existing drug-impaired driving laws — shortly after pot legalization may have had an effect on the results of the study.

“These new traffic-safety laws imposed more severe penalties for impaired driving due to cannabis, alcohol, and combined cannabis and alcohol use,” he said.

Under the new traffic-safety laws, a cannabis-impaired driver with THC (the main psychoactive compound in cannabis) blood concentrations between two and five nanograms per millilitre of blood within two hours of driving faces a summary conviction and a $1,000 fine.

While UBC report points to no increases in traffic injuries, OPP data showed the number of drug-impaired driving cases has increased from 261 in 2018 to 590 in 2020 — an increase of 126%.

OPP records also showed the number of collisions from drug-impairment increased from 123 in 2018 to 260 in 2020 — a spike of 111%.

Nationwide, a Statistics Canada report found the police-reported impaired driving rate increased by 19% in 2019 from 2018, ending a downward trend that began in 2011.

The report, titled Impaired Driving in Canada, found police reported 6,453 incidents of drug-impaired driving in 2019, representing 8% of all incidents of impaired driving and a 43% increase over 2018.

Based on crime stats from prior years, the Statistics Canada report also said police services in Canada were already stopping an increasing number of drug-impaired drivers before cannabis became legal.


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