Do medical marijuana laws reduce crime? : an empirical approach to drug enforcement policy and its effect on criminal activity

Abstract

This paper studies the effect of medical marijuana law on different types of crime reported. The effect these laws have on society seems to be bigger than just through the community of medical marijuana users. With data from the Uniform Crime Reports we are able to exploit the fact that states passed this law at different points in time. This variation of the implementation of the law gives us the possibility of, by using a Dif-in-Dif approach, analyze panel data. After controlling for state and year fixed effects, as well as other variables, we find that reported index I crimes fall a 3.79% relative to states who were never treated. Index I crime’s components are further analyzed and we find that property crimes seem to be responsible for this drop. Property crimes suffer a 4% fall in crimes reported in states that enact medical marijuana relative to those who do not. We argue that several mechanisms generate a change in law enforcement resource allocation and try to approach econometrical proof that law enforcement is reallocating resources after medical marijuana law has been enacted. After this we try to better assess the nature of this re-allocation. Our study tries to anticipate impending research on marijuana policy and its effect on society, brought on by the recent legalization of recreational marijuana in Colorado and Washington.