Cannabis Liberalization in the US: The Policy Landscape

State cannabis policies are inconsistent across jurisdictions and often conflict with federal policy.

Conflicts in evidence on the public health effects of legalizing recreational cannabis also exist. Research is needed to help support policymakers in addressing inconsistencies related to cannabis liberalization; improve the safety of cannabis supply; sort through potential health and substance use disorder impacts; and combat health and criminal justice disparities.

What’s the Issue

Research suggests that cannabis—or marijuana—use is associated with potential therapeutic benefits, but also individual health harms, particularly for adolescent populations. Inconsistencies exist between federal and state cannabis policies, with a need to explore the implications of that disconnect. Increasing numbers of states are decriminalizing cannabis possession and legalizing its medical and recreational uses with little regulation to ensure product safety. Yet under federal law, cannabis remains prohibited because of the potential for drug misuse and negative health consequences. In fact, the production, sale, possession, and distribution of cannabis can carry fines and prison time under federal law today with persistent racial disparities in cannabis-related arrests. In contrast, as public support for legalization has increased, states have begun liberalizing cannabis policy. By November 2020, 16 states had repealed criminal penalties, making the substance available for medical and recreational use. Today, more than two-thirds of Americans live in one of the 36 states and four territories that have approved medical cannabis use. Liberalization in cannabis laws relates to a decline in the public’s perceived great risk from smoking cannabis among people ages 12 and older.

Legalization of cannabis for recreational use relates to key population health outcomes, including cannabis use disorder, cannabis-related hospitalizations and poisonings, driving safety, and other substance use. Although laws passed in more recent years (2009–2017) feature regulatory programs that prioritize product safety, provisions among jurisdictions differ from each other. Cannabis food and drink products pose unique regulatory challenges. Health risks associated with edibles, including for minors, likely result from minimal consistency across products related to potency and inaccurate labeling. More research is warranted regarding accuracy of perceptions about risk, as well as health benefits and harms associated with expanded cannabis access.

What’s Next

The persistent divide between national and state policy and the growth of state cannabis markets present numerous challenges for population health, in part because the safety of many cannabis products is uncertain and varies from state to state. Cannabis policy liberalization provides opportunities for therapeutic benefit but also presents the potential for health harms—the full consequences of which remain unknown due to a dearth of evidence. For instance, federal law requires the use of federally supplied cannabis for clinical trials, which fails to reflect the potency and type of cannabis products that are grown and consumed within states.

Policy reforms that will address criminal justice and social disparities warrant consideration. Examples include legalization initiatives in New Mexico, New York, and Virginia in 2021 that incorporate reforms to address harms experienced by communities disproportionately affected by cannabis. Because evidence on the effects of cannabis liberalization on population health is limited, policymakers should adopt a public health–informed approach to legalized cannabis supply. Key understudied areas include features of legal cannabis markets; policy effects across different populations; and characteristics of cannabis supply, such as price, potency, and product type.

Policy approaches can address inconsistencies between federal and state law; offer regulatory oversight to improve the safety of cannabis supply; and combat inequities arising both from the war on drugs and from disparities in access to newly legal supply chains. As states begin to implement social equity measures, they should carefully assess which communities have been disproportionately harmed by both cannabis prohibition and liberalization; how to encourage equitable training and business support in the cannabis industry; and how earmarked cannabis revenue will be disseminated to equity-enhancing initiatives. Some states have included provisions within their legalization initiatives that require policy evaluation. For example, Washington state earmarked cannabis tax revenue to fund a continuous cannabis research program. More efforts such as these will help to uncover comparative health harms and benefits of various cannabis policy and regulatory approaches.