The Impact of Marijuana Legalization on Marijuana and Alcohol Use and Traffic Fatalities

Abstract

An increasing number of states have legalized marijuana for medicinal purposes and some for recreational use. The social and health impacts resulting from the change in marijuana legalization remains unclear. The goal of this dissertation was to examine the heterogeneity in marijuana policy across states and the relationship with traffic fatalities and substance use. In the first manuscript, I examined medical and recreational marijuana policy components and developed a measure of policy restrictiveness. Example policy components included patient registration requirements, possession limits, and cultivation restrictions. Medical marijuana policy components varied across states, while recreational marijuana policies were more homogenous across states. In the second manuscript, I examined the trends in attitudes toward marijuana legalization and the relationship between attitudes and marijuana use over time. Data were drawn from Monitoring the Future study. Among 12th graders in 2017, the proportion that favored marijuana legalization was at a historic high of 49%. Favorable attitudes toward legalization were related to an increased odds of marijuana use. In the third manuscript, I examined the relationship between marijuana legalization and traffic fatalities. Enactment of a marijuana policy was associated with a decrease in traffic fatalities compared with states that did not enact marijuana policies. However, among states that legalized marijuana, states that had less restrictive policies had more traffic fatalities compared with states with more restrictive policies. Understanding the public health impact of marijuana policies is critical, given the rapidly shifting policy context. Findings here suggest that examining policy restrictiveness is an important component for understanding the influence of marijuana legalization.