How Do Adult Laws Affect Youth Marijuana Use?

OBJECTIVE: To examine the effect of changing marijuana laws on adolescent marijuana use and attitudes towards marijuana use.

METHODS: From years 2009 to 2014, a school-based survey was conducted in the U.S. among approximately 32,000 6^th-12^th-grade students, across 26 states. Students self-reported marijuana use, as well as approval levels of peer marijuana use for their closest friends. Distinctions were made between schools in states with legal recreational marijuana use, legal medical marijuana use, and illegal marijuana use. Logistic regression was used to examine the effect of shifting marijuana laws on adolescent use and attitudes towards use.

RESULTS: Relative to U.S. students in states where marijuana use is illegal, students in grades 6-12 were more likely to have used marijuana in the past 12 months if their state medicalized marijuana (OR 1.5, 95% CI 1.4, 1.6), or if their state legalized recreational marijuana use (OR 2.6, 95% CI 2.2, 3.0). In addition, students in states with medicalized (OR 1.3, 95% CI 1.2, 1.5) or legal recreational marijuana use (OR 1.5, 95% CI 1.2, 1.8), were more likely to approve of a peer’s occasional use of marijuana, compared to students in states where marijuana use if illegal.

CONCLUSION: Policy changes meant to target adult use of marijuana have significant effects on adolescent marijuana use and attitudes towards marijuana. In the changing social and political climate, it should be a top priority to continually collect current, relevant marijuana perception and use data among youth. This data is powerful in tracking on-the-ground changes, in real time, and could be a powerful influence on lobbyists, voters, and particularly adults working in health promotion.