The Impact of Marijuana Legalization on Adolescent Use, Consequences, and Perceived Risk.

BACKGROUND: Currently, only four states have legalized recreational marijuana use for adults over 21 years of age. Therefore, little is known about the influence that legalization will have on adolescent marijuana use.

OBJECTIVES: This study examines how marijuana legalization has impacted the frequency and consequences of adolescent use in a sample of participants in a school-based, substance use intervention. We hypothesized that adolescents enrolled in the intervention in years after marijuana legalization would present with more problematic use compared to those enrolled prior, and that changes in the perceived risk of marijuana would be a mechanism of problematic use.

METHODS: Participants were 262 students enrolled in a school-based substance use intervention in 2010 to 2015. The Customary Drinking and Drug Use Record, Alcohol and Drug Use Consequences Questionnaire, and a decisional balance matrix were used to assess marijuana frequency, negative consequences, and perceived risk of use. A mediation model was used to test the degree to which marijuana legalization may lead to increased frequency and consequences of use through perceived risk.

RESULTS: Findings indicated a significantly positive correlation between marijuana-related consequences and perceived risk post legalization. Despite relatively equal use between both groups, adolescents in the legalization group experienced higher levels of perceived risk and increased negative consequences.

CONCLUSIONS/IMPORTANCE: Due to the rising legalization status of marijuana in the United States, it is imperative that psychoeducation is provided to adults and adolescents about the consequences of underage marijuana use.