Five years later, researchers say the impacts of legalizing cannabis in Canada have been mixed

Dasi Menakadasi holds a joint while smoking marijuana to celebrate the legalization of recreational cannabis, in Vancouver, on Wednesday October 17, 2018. THE CANADIAN PRESS/Darryl Dyck

Five years after Canada's move to legalize the recreational use of cannabis, researchers say the policy's impact has had mixed success on public health goals and justice reform since 2018.

According to a report by the Canadian Medical Association Journal published Tuesday, trends over the last few years have seen fewer incriminating activity related to cannabis use as well as increasing health concerns.

"Cannabis legalization in Canada appears not to have been the public health disaster anticipated by some of its opponents, but it cannot be described as a comprehensive or unequivocal success for public health either," the study authors wrote.

While the daily use of cannabis among users has remained stable since legalization, Statistic Canada reported an overall increase of cannabis use from 22 per cent to 27 per cent among Canadians aged 16 and older between 2017 and 2022. Use among Canadian youth, meanwhile, has remained at similar levels as 37 per cent of 16 to 19 year olds reported using cannabis in 2022 compared to 36 per cent in 2018.

Since legalization, one report found emergencies related to cannabis-linked disorders and poisoning among youth in Ontario and Alberta rose to 20 per cent. A separate report analyzing unintentional cannabis poisoning from edibles among children in Ontario, Alberta, British Columbia and Quebec found these emergency visits increased substantially since edibles were legalized in 2019.

A total of 581 pediatric hospitalizations were reported since 2015 — 105 were reported during the first 14 months of legalization and 356 were reported during the first 19 months of the legalization of edibles.

Health Canada has previously warned cannabis users and those with children to be aware of edible products that look like ordinary candy or pastries and are packaged into colourful, sometimes familiar-looking snacks to most.

However, there have been some improvements to the frequency of Canadians purchasing illegally produced cannabis since legalization, as data has shown two-thirds of users purchase cannabis products from legal sources now.

Additionally, levels of driving impairment over cannabis use has slightly decreased or stabilized in most parts of the country, except for British Columbia, where rates of impaired drivers increased between 2018 and 2020 in comparison to 2013 and 2018.

A separate report from the Canadian Centre on Substance Use and Addiction also reported a drastic 97 per cent reduction in cannabis possession charges among youth between 2015 and 2019. Additionally, trafficking and sales charges among youth also decreased from 12 to eight per cent.

The study authors noted that while Canada's legalization of non-medicinal cannabis has resulted in a mixed outcome, the last five years can't summarize the policy's full impact on Canadians.

"Robust ways to integrate diverse data when evaluating policy outcomes are also needed to inform evidence-based adjustments to regulatory parameters that may be necessary to more effectively serve and achieve the declared public health objectives of cannabis legalization in Canada going forward," the authors wrote.