The purpose of this research is to provide insight into the political economy of medical marijuana laws and the role diverse interest groups play in shaping drug regulation. This research tests the claims of marijuana activists that asset forfeiture and lobbying of law enforcement groups has impeded the relaxation of marijuana regulation. This is accomplished by examining the effect of law enforcement collective bargaining and the proportion of seized assets returned to law enforcement agencies on the passage of medical marijuana laws between 1990 and 2010.