Increasing access to medical marijuana could decrease murder and robbery rates, according to new research out of Haverford College’s Department of Economics.
“Previous research has analyzed the effects of the implementation of medical marijuana laws on crime rates, but this paper is the first to study how the size of the medical marijuana market affects crime rates”, states the study’s abstract. By using the medical marijuana patient registration rates across states from 1995 to 2015, lead researcher Matthew Incantalupo used “a difference-in-differences approach to find that a one percent increase in medical marijuana registration rates decreases murder and robbery rates by 0.03% and 0.02%, respectively, and has no significant effect on other types of crime.”
According to the study, these results “show that increasing the legal availability of marijuana through medicalization could decrease murder and robbery rates, two crimes highly associated with the illegal drug trade.”
A University of Texas study released in 2014 came to a similar conclusion, finding that the enactment of laws legalizing medical cannabis are associated with reductions in rates of homicide and assault.
The full study can be found by clicking here.