Study: Police Solve More Violent Crimes After Cannabis Legalization

The legalization of adult-use cannabis is associated with increased clearance rates for varying types of violent crimes according to a study soon to be published in the International Journal of Drug Policy, outlined by NORML. Researchers from the University of Utah and the University of China looked at crime clearance rates in Oregon and control states prior to and post adult-use cannabis legalization.

The clearance rate for violent crime represents the proportion of violent crimes solved — meaning when an arrest is made and charges are laid — versus all violent crimes that are reported to the police.

Researchers found “significant increases in the clearance rate for overall violent crimes and for aggravated assault in Oregon counties relative to those in non-legalized states following legalization.”

“These conclusions reaffirm the notion that states can sensibly regulate the adult use and sale of cannabis in a manner that doesn’t adversely impact public safety. Moreover, in some cases, legalization may contribute to an environment that positively affects police officers’ performance in solving serious crimes.” — NORML’s Deputy Director Paul Armentano, in a statement

Titled “Recreational marijuana legalization on clearance rates for violent crimes: Evidence from Oregon,” the paper found, however, that the positive effects of legalization on clearance rates “appear to reduce over time.” Additional research is also needed on the effect of adult-use cannabis legalization on police performance and clearance rates, investigators wrote.

A 2019 study, also outlined by NORML, noted a similar increase in the clearance rates for violent crime following the legalization of cannabis in Washington state and Colorado.