The enactment of medicinal cannabis laws is not associated with any rise in statewide criminal activity and may even be related to reductions in incidences of violent crime, according to data published online in the journal PLoS ONE.
Researchers at the University of Texas at Dallas tracked crime rates across all 50 states between the years between 1990 and 2006, a time period during which 11 states legalized marijuana for medical use. Authors reviewed FBI data to determine whether there existed any association between the passage of medicinal cannabis laws and varying rates of statewide criminal activity, specifically reported crimes of homicide, rape, robbery, assault, burglary, larceny, and auto theft.
Investigators reported that the passage of medical marijuana laws was not associated with an increase in any of the seven crime types assessed, but that liberalized laws were associated with decreases in certain types of violent crime.
“The central finding gleaned from the present study was that MML (medical marijuana legalization) is not predictive of higher crime rates and may be related to reductions in rates of homicide and assault,” authors reported. “Interestingly, robbery and burglary rates were unaffected by medicinal marijuana legislation, which runs counter to the claim that dispensaries and grow houses lead to an increase in victimization due to the opportunity structures linked to the amount of drugs and cash that are present. Although, this is in line with prior research suggesting that medical marijuana dispensaries may actually reduce crime in the immediate vicinity.”
Researchers concluded: “Medical marijuana laws were not found to have a crime exacerbating effect on any of the seven crime types. On the contrary, our findings indicated that MML precedes a reduction in homicide and assault. … In sum, these findings run counter to arguments suggesting the legalization of marijuana for medical purposes poses a danger to public health in terms of exposure to violent crime and property crimes.”
Full text of the study, “The Effect of Medical Marijuana Laws on Crime: Evidence from State Panel Data, 1990-2006,” appears online here.