In 2018, Canada was the first G-20 nation to undertake major liberalization of its cannabis policy by implementing the legalization of nonmedical cannabis use and supply for legal-age adults, including commercial, regulated cannabis production, and retail systems. The aims of the legalization policy were to improve cannabis-related public health outcomes, prevent cannabis use among youth, and reduce cannabis crime and illicit market. ¹ The federal Cannabis Act set the central legal framework for minimum standards, while allowing variations in provincial/territorial regulations for key parameters (e.g., regarding legal use age, retail distribution models, home-growing, places of use) and so creating a heterogeneous patchwork of regulatory sub-systems across the provinces and territories. ¹ By 2024/2025, there were some 3,700 licensed cannabis retailers and 1,000 cultivators/producers, with an annual sales volume of $5.5billion contributing an estimated $16 billion to Canada's GDP. Following a rapid initial ramp-up, it can be assumed that legal cannabis markets have matured to a relatively steady state by now.

Recent insights on essential indicators for cannabis use and related health outcomes several years post-legalization come from a variety of population-based data sources—including the national Canadian Cannabis Survey (2023) and the Canadian Substance Use Survey (2024), together with the CAMH Monitor (2025) from Ontario, Canada's most populous province.^{2bibr3-07067437261454772–4} Data from these sources, when viewed together, indicate that some 26–32% of Canadian general population adults are currently active (i.e., past 12 months) cannabis users, thus pointing to substantial increases in the prevalence of cannabis use associated with legalization compared with prior periods.^{2bibr3-07067437261454772–4} Notably, the prevalence of cannabis use among youth (e.g., 15- to 19-years-olds)—a subgroup that predominantly consists of underage individuals without legal cannabis access and was highlighted as a priority for prevention by legalization's objectives—has steadily stood at substantially higher levels of 40% or above.

About one-in-four (25%) of active cannabis consumers use cannabis on a daily/near-daily basis—an intensive use pattern that commonly involves high-potency products and that is strongly associated with various—acute and chronic—cannabis-related harms (e.g., cannabis use disorder, mental health problems)^{.2bibr3-07067437261454772bibr4-07067437261454772–5} Depending on the survey source, 40–60% of past-year users were estimated by the ASSIST's cannabis involvement scale to be at moderate-to-high risk for cannabis use-related problems, a proportion that has been increasing over-time.^2,3 Nationally, cannabis-related hospitalizations increased from 23,322 in 2017/18 to 34,013 in 2024/25; in Ontario, the annual numbers of both cannabis-related Emergency Department visits (5,645–12,424) and cannabis-related hospitalizations (4,215–7,793) approximately doubled between 2015 and 2024. In addition, numerous other studies have documented increases for a variety of severe cannabis-related physical (e.g., poisonings, injuries) and mental health (e.g., psychosis, self-harm) harms associated with legalization. ⁶

Other data indicate developments regarding key cannabis-related risks relevant for users and/or others’ health. For example, as many as 20–24% of active (past-year) cannabis users have reported driving a motor-vehicle immediately after consuming (e.g., smoking/ingesting) cannabis products, a leading cause of cannabis-related injury and/or death due to impairment.^{2bibr3-07067437261454772–4} These rates seem steady, but are comparably high (e.g., when compared to alcohol-impaired driving). The majority (57%) of CCS respondents reported that they had been exposed to second-hand cannabis smoke (mostly in public places) in the past year, suggesting substantial potential for adverse cannabis use-related effects on others. ³

Contrary to trends in health-related outcomes, there have been large decreases in selected cannabis-related crime indicators since legalization in Canada. While there were some 70,000 police-recorded cannabis offenses—mostly for personal possession—in 2014 just prior to legalization, this annual number of enforced cannabis incidents has vastly dropped to 8,879 offenses (with only a small proportion [13%] for possession) in 2024 and so markedly reduced the cannabis-related enforcement burden. ⁷ Among persons who indicated cannabis use in the past year, 72% reported that they had procured their cannabis products from a legal/licensed source in 2024; three-quarters (77%) of these indicated that they “always” or “mostly” did so, thus reflecting a gradual but major shift from illegal to legal sourcing practices associated with legalization. ³ But while there have been substantive reductions in the criminalization of cannabis consumers and similarly marked shifts toward obtaining cannabis from legal sources, it is largely unclear how illegal cannabis production and supply markets have evolved.

Almost a decade into the implementation of cannabis legalization policy in Canada, the overall picture of health- and crime-related outcome indicators associated with it is notably mixed and bifurcated. While some of these developments may have been driven by independent factors, there have been marked increases in cannabis use prevalence and cannabis-related health problem outcomes associated with legalization, which presumably translate into an overall increased cannabis-related burden of disease post-legalization. At the same time, the majority of legal-age cannabis consumers are now obtaining their cannabis products from legal/licensed sources, so avoiding involvement with and sustaining illicit cannabis markets. Related, the extensive burden of—mostly user-focused—cannabis enforcement and criminalization that existed before legalization has been vastly reduced, averting tens-of-thousands of cannabis-related arrests and related adverse consequences of personal, professional, and social hardship that would have been expected in its absence.

A crucial question for policy makers is: Is this rather mixed outcome picture of marked increases in cannabis use and related health problems, and decreases in cannabis use-related crime and enforcement generally acceptable for legalization as the chosen policy reform option for cannabis control in Canada? Some views—over and beyond the policy's formal objectives—may pragmatically suggest that this represents an acceptable trade-off, where much of the excessively adverse effects of punitive and costly criminalization appear to be offset by increases in cannabis use and/or related health harms among its consumers.

We note, however, that this is not the overall outcome scenario that should be welcomed and used to justify legalization. Legalization policy was introduced and promoted as an approach that would both reduce the burden of cannabis crime and improve public health, including better protection of youth when it comes to cannabis use prevention. In this context, we believe that an increased cannabis burden of disease is not a satisfactory result and that policy-makers should strive to deliver better overall outcomes for legalization. Importantly, there are several important policy levers that could be used to reduce the adverse health outcomes observed with targeted and evidence-supported measures.

For example, the social acceptability of regular cannabis consumption has risen in legalization contexts, indicating an “normalization” dynamic for cannabis use that commonly implies a “risk-free” activity that requires addressing through effective and age-appropriate messaging.^1,3 Second, extensive amounts of cannabis consumption now involve high-potency/strength cannabis products (e.g., >20% THC) associated with elevated risk for adverse health outcomes (e.g., psychosis, CUD), especially for vulnerable (e.g., youth) consumers that should be subject to age-appropriate education and consideration of access restrictions. ⁵ Third, cannabis use levels among underage youth—a subpopulation for whom cannabis access is illegal and was to be reduced through legalization—remain unacceptably high. Improved interventions, including better use prevention and efforts to curtail common (e.g., social) cannabis sourcing routes, appear required. ⁸ Fourth, preventive education and/or deterrence-oriented enforcement measures for cannabis-impaired driving appear to be falling short, and require targeted intensification for increased effectiveness. Fifth, there are signs of “commercialization creep” among cannabis production/retail sectors, including commonplace violations of regulatory restrictions on cannabis advertising/promotion supposed to protect vulnerable (e.g., underage) groups from inducements.^3,9 Yet, the cannabis industry has lobbied to further relax related restrictions. Each of the above and other areas provide acute opportunities for improved policy regulations and/or tailored interventions toward reducing cannabis-related health harms and burdens in the Canadian population that should be a foremost goal of legalization policy.

Nonmedical cannabis legalization in Canada was a milestone policy reform when implemented almost a decade ago. However, complacency about its presently main outcomes would be misplaced, also since its original objectives have been at best partially achieved. There is an urgent need for targeted and effective measures and interventions to improve on the policy's overall—mainly health-related—impacts while supporting ongoing monitoring and evaluation.^1,6,8 It is not sufficient to suggest that legalization simply “traded off” an excessive burden of cannabis crime for increases in use and health problems in the population, especially considering the public health-centered objectives in spirit with which the policy was originally advanced. There are multiple evidence-based policy and regulation levers available for utilization by policy-makers especially to reduce the current burden of adverse health outcomes to ensure that cannabis legalization equally and effectively serves to reduce both related health- and crime burdens in Canada.