Conclusion: After cannabis legalization, the prevalence of moderately injured drivers with a THC level of at least 2 ng per milliliter in participating British Columbia trauma centers more than doubled. The increase was largest among older drivers and male drivers. (Funded by the Canadian Institutes of Health Research.)
(According to recently released data from The Victorian Institute of Forensic Medicine, Cannabis was present in 14.8 % of driver fatalities, almost as much as all combined stimulant involvement in driver fataliies at 17.3 %)