Examining the predictors of medical marijuana legalization in the United States using an empirically based taxonomy approach

The legalization of medical marijuana in states of the United States is currently a controversial topic. Despite conflict with the federal government, 33 states have legalized medical marijuana and other states are currently considering adopting the law by the year 2019. Why do some US states adopt medical marijuana laws (MMLs) and others do not? This study examines the diffusion of MMLs by analysing policy adoption from morality and economic development policy perspectives. This study finds that the morality perspectives of states - religious groups, citizens' liberal ideology, and a ballot initiative process - have a significant effect on the adoption of medical marijuana laws. Economic indicators - fiscal capacity growth, incarceration, and the cost of the justice system - also have a significant effect on adoption. Marijuana users and the state regulatory environment are also important predictors of the diffusion. Overall, this study finds that the adoption and diffusion of MMLs is mainly determined by the opinions of citizens rather than the political ideology of elected officials or the government's fiscal health conditions. In addition, the study finds that the multidimensional policy model provides a better explanation for this than either of the single policy perspective models.