Is There A Relationship Between the Legalization of Medical Marijuana and Youth' Beliefs about Marijuana?

Introduction: To date, 16 U.S. states and the District of Columbia have legalized medical marijuana. Montana passed the Medical Marijuana Act in 2004 making it legal to possess and use marijuana for medical purposes. Studies have suggested that youth marijuana use may be higher in states that have legalized medical marijuana. A possible explanation is that legalization establishes a normative climate that is supportive of marijuana use. This study examines the relationship between marijuana-related norms among youths (dependent variables), number of medical marijuana cards at the county-level, and adult marijuana use norms as indicated by the percent of voters who approved legalization of medical marijuana in 2004.  

Methods: Survey data collected in 2010 from 17,482 youths (8^th, 10^th, and 12^th grade) were analyzed using hierarchical linear modeling. Survey data were supplemented with county-level archival data, including the number of votes cast for the legalization of medical marijuana (Measure 148) in 2004 and the number of medical marijuana cards. In order to investigate the role of marijuana norms, two models were examined. Model 1 included background variables (gender, age, race, parents’ education) and the number of medical marijuana cards in each county, and Model 2 included all of Model 1 variables plus the percentage of yes votes for Measure 148.

Results: Based on Model 2, youths in counties with more votes for the legalization of medical marijuana were more likely to perceive smoking marijuana as cool and as less harmful compared to youths in counties with fewer votes for Measure 148. Teens’ perceptions of how wrong it was to smoke marijuana were negatively related to votes for Measure 148. Perceptions of how wrong parents and neighbors thought it was to smoke marijuana were negatively related to the number of medical marijuana cards in the county. Perceived use by friends and siblings was positively related to medical marijuana cards in Model 1 but that relationship was no longer significant in Model 2. Perceived use by peers and intentions to smoke marijuana as an adult were positively related to votes for Measure 148.  

Conclusion: This study suggests that marijuana-related beliefs held by youths are positively related to votes for Measure 148, suggesting that votes for medical marijuana may reflect a more tolerant attitude towards marijuana use in general. These findings highlight the importance of the normative environment in which youths live and suggest that the environment may account for youths’ perceptions about marijuana. Prevention efforts should focus on changing the norms in communities that are favorable to marijuana use.