Using Existing Data to Advance Knowledge About Adolescent and Emerging Adult Marijuana Use in the Context of Changes in Marijuana Policies (original) (raw)

Although marijuana remains an illegal substance under US federal law, there have been substantial and geographically widespread changes in state policy since 1996. As of October 2018, nine states and the District of Columbia had both medical marijuana laws (MMLs) and recreational marijuana laws (RMLs), and an additional 22 states had MMLs only (National Conference on State Legislatures [NCSL] 2018). In the November 2018 election, Utah and Missouri passed MMLs and Michigan-which already had an MML-passed an RML (Hauser 2018). Approximately twothirds of US residents currently live in states with MMLs or RMLs, or both. Although the loosening of state-level restrictions on marijuana has been framed as beneficial for reducing the human, social, and economic costs associated with a criminal justice approach (Hawken et al. 2013), it has also spurred concerns about possible public health consequences, particularly for young people (Compton et al. 2017; Hasin 2018). These include potential increases in use of marijuana and other substances, substance use disorders, marijuana-related motor vehicle crashes,