Marijuana has become one of the most used taboo substances in the United States in the past few decades. Recent literature, as well as literature dating back to the early 2000s, have looked at how marijuana legalization and decriminalization can impact crime rates. However, there is little empirical evidence connecting marijuana legislation to crime rates. This paper uses state-level crime data from the FBI and the National Census Bureau to examine the effect of marijuana legalization and decriminalization on both violent and property crime rates. We use a fixed effects model in order to estimate the effect of marijuana legalization and decriminalization on states’ crime rates over time. We find that legalization has a positive effect on property crime over time in a state, and that legalization increases both violent and property crime rates across states.