Adolescent cannabis use during a period of rapid policy change: Evidence from the US PATH Study
Background: Given rapidly shifting cannabis policies in the US, we consider the effect of these changes on adolescent cannabis use.
Method: We use the restricted access youth cohort of the Population Assessment of Tobacco and Health (PATH) Study, a recent (2013-2019), longitudinal, and nationally representative dataset, to assess whether changes in cannabis policy affect youth cannabis use (N=26,673). Multilevel and fixed effects regression models are used to examine adolescent past-month cannabis use.
Results: Multilevel models showed that compared to states where medical cannabis is fully legal, the odds of adolescent past-month cannabis use are lower in states where it is legal with restrictions (OR=0.718; p<.01) or illegal (OR=0.608; p<.001), and in states that allow CBD only (OR=0.520; p<.001), controlling for other covariates. Similarly, compared to states where cannabis possession is legal, the odds of past-month youth use are lower in states where possession is decriminalized (OR=0.762; p<.01) and where it is criminalized (OR=0.667; p<.001). Fixed effects models showed that the odds of past-month cannabis use are lower (OR=0.574; p<.05) in years when a respondent’s state allowed only CBD compared to years when the state had legalized medical cannabis. Finally, the odds of past-month cannabis use are lower (OR=0.634; p<.01) during years when a respondent’s state had decriminalized cannabis possession compared to years when it was legalized.
Conclusion: Liberalized cannabis policy had a significant effect on recent adolescent cannabis use. The most consequential policy shift that affects adolescent use is from decriminalization to legalization, such that states making this change should consider additional prevention efforts.