Since California legalized medical cannabis almost three decades ago, support for relaxed laws around the Schedule I substance has spread throughout the United States. More than three-fourths of states permit medical use, and more than one-third have legalized recreational adult consumption. As 91 percent of U.S. adults now support some degree of regulated legalization and politicians on both sides of the aisle are seeking federal decriminalization, this legislative trend is likely to continue.
Nonetheless, a number of national and community groups continue to speak out against cannabis legalization, voicing concerns about public health and safety. In this paper, we analyzed eight anti-cannabis efforts to identify several salient public health-related fears, assessed the validity of those claims and considered relevant implications for policy.
Our analysis of state and national efforts against cannabis legalization revealed five priority concerns: rising tetrahydrocannabinol (THC) levels; the connection between cannabis use and mental health conditions; youth consumption; accidental poisonings, particularly among children; and the effect of cannabis intoxication on driving. In-depth reviews of the literature around each of these concerns showed that the issues tend to be highly nuanced. THC levels do appear to be higher than in the past, but this may be due to consumer preferences and market pressures, not exclusively or even primarily due to legalization. Cannabis consumption is linked to several mental health issues, but evidence on causal connections remains absent for some conditions and inconclusive for others. Legalizing cannabis for either medical or recreational adult consumption has not had any significant effect on past-30-day use among teens. Increased access to certain products that are more common in illicit markets—such as edibles—may be driving an increase in accidental consumption among children, but the overall numbers remain extremely low. And while THC likely does cause some driving impairment in most people, the extent of that impairment varies drastically from one person to another and is very difficult to assess.
These findings suggest that although cannabis is not risk free, most negative consequences can be mitigated through smart policy. As such, given the continuing trend toward legalization in the United States, we recommend several ways that federal, state and local entities can support harm-reducing approaches that will protect both consumer safety and autonomy across the country’s discrete regulated cannabis markets.
Our policy recommendations include federal standards for and state regulation of dosing, potency and labeling; increased research and support for pilot programs to develop evidence-based strategies to assess cannabis-impaired driving; and continued support for youth-prevention efforts such as age minimums, compliance checks and targeted, fact-based prevention media.
This paper shows that although some of the concerns expressed by anti-legalization campaigns stem from the scientific literature, most reflect an incomplete picture and may be largely inaccurate. Cannabis’ risks to public health and safety are manageable, and targeted and evidence-based policy can ensure safe, legal markets for medical and recreational use.
In 1996, California became the first U.S. state to legalize medical cannabis. Since that time, cannabis laws have gradually relaxed throughout the country despite barriers resulting from the drug’s federal Schedule I status. As of February 2022, 38 states and Washington, D.C. allow medical cannabis, and 18 states and Washington, D.C. permit recreational adult use. That momentum is likely to continue: a 2021 survey found that 91 percent of U.S. adults supported legalizing medical cannabis, and 60 percent believed it should be legal for both medical and adult recreational consumption. Already in 2022, legislatures and citizens in more than two dozen additional states have proposed legalizing and regulating recreational cannabis for adult consumption, and federal decriminalization is rapidly gaining traction among Republicans and Democrats alike.
Despite growing support for cannabis legalization and regulation, efforts to loosen cannabis laws consistently meet with opposition from national- and state-level organizations. Communities and special interest groups raise concerns about a range of perceived public health and safety consequences of cannabis use and intoxication. Nonetheless, the legislative momentum is likely to persist. As such, to help states consider these issues through an evidence-based lens, this policy paper will:
Identify and evaluate the validity of five primary health and safety concerns about cannabis use and intoxication with tetrahydrocannabinol (THC)—the primary compound responsible for the drug’s trademark “high”—commonly raised by opponents of legalization.
Highlight relevant policy implications.
Read the full paper here .
Press release: Cannabis Concerns: Fact or Fiction? 
Image: ryland zweifel 
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- “Read the full paper here”: https://www.rstreet.org/wp-content/uploads/2022/04/Final-Study-No.-253.pdf
- “Cannabis Concerns: Fact or Fiction?”: https://www.rstreet.org/2022/04/13/cannabis-concerns-fact-or-fiction/
- “ryland zweifel”: https://stock.adobe.com/contributor/207939441/ryland-zweifel?load_type=author&prev_url=detail