A new study finds legalizing cannabis hasn’t increased traffic injuries in Canada. Cannabis became legal at the end of 2018 in Canada, and researchers decided to look at Ontario and Alberta emergency department data from between 2015 and 2019 to see how many traffic injuries were occuring. They found there was no significant increase in people going to the emergency room with traffic injuries post-legalization.

“Implementation of cannabis legalization has raised a common concern that such legislation might increase traffic-related harms, especially among youth,” says study author Dr. Russ Callaghan. “Our results, however, show no evidence that legalization was associated with significant changes in emergency department traffic-injury presentations.”

Sheila Vakharia, deputy director of the Department of Research and Academic Engagement at the Drug Policy Alliance, told Cannabis News Box that this study is a bit different from the ones she’s seen in the U.S.

“This study didn’t actually find that crashes decreased (or increased) because they weren’t actually counting crashes before and after
legalization,” Vakharia said. “This study found that there were no increases in emergency room visits for adults or youth after being in a traffic accident when they compared numbers pre-legalization to post-legalization. This is still a meaningful outcome, because only serious injuries make it to the emergency department and this study suggests there were no more serious traffic-related injuries that required medical intervention compared to prior to legalization.”

Many who oppose legalizing cannabis argue that there will be more traffic injuries and traffic accidents generally if the U.S. legalizes cannabis, and the data appears to show this is not the case. Even in states that have legalized cannabis,  the traffic laws aren’t always in line with what makes sense based on what the data shows makes the most sense.

“The problem with a lot of impaired driving policies in states is that they heavily rely on testing biological specimens like urine or blood to determine that a driver was impaired when involved in a traffic infraction, accident, or fatality,” Vakharia said. “Unfortunately, this is not a reliable way to determine whether someone was actually impaired in the moment or had simply used a marijuana product recently enough that they could still test positive for metabolites.”

Vakharia said this can “overinflate” estimates of how many people are driving while impaired or involved in traffic infractions while under the influence. It can also subject cannabis users to harsher penalties because they test positive even if they may not have consumed cannabis recently.