The 2018 legalisation of cannabis in Canada was not associated with increases in traffic injuries, a study from the University of British Columbia has found.
The study by Medical Program Professor Dr Russ Callaghan examined data on traffic injuries recorded by the emergency departments in the Canadian provinces of Alberta and Ontario. Analysis of the data showed there was no evidence of significant changes in traffic injury emergency department visits among all drivers immediately after cannabis legalisation.
Callaghan said that there was a reported increase in users of cannabis after legalisation, but the number of people reported driving within two hours of cannabis use has gone down. “Implementation of cannabis legalisation has raised a common concern that such legislation might increase traffic-related harms, especially among youth,” said Dr Callaghan. “Our results, however, show no evidence that legalisation was associated with significant changes in emergency department traffic-injury presentations.”
Dr Callaghan admitted he was surprised by the results, expecting to see more cannabis-impaired driving leading to increases in traffic-related injuries. “It is possible that our results may be due to the deterrent effects of stricter federal legislation, such as Bill C-46, coming into force shortly after cannabis legalisation. These new traffic-safety laws imposed more severe penalties for impaired driving due to cannabis, alcohol, and combined cannabis and alcohol use.”
The study, published in Drug and Alcohol Dependence, an international peer-reviewed scientific journal, will be followed by a further study on traffic fatalities in Canada from 2010-2020, due in the summer of 2022.