Study Finds Marijuana Legalization Decreases Crime Rates

Washington State University researchers took a look at legalization and law enforcement effectiveness in Washington and Colorado. Their research showed that marijuana legalization has “produced some demonstrable and persistent benefit” in solving other crimes. The findings were published in the journal Police Quarterly.

The researchers looked at trends in crime clearance rates in Colorado and Washington, according to The Washington Post. Recreational sales didn’t start in either state until 2014, but laws regarding personal possession/use were in effect prior to sales beginning. Violent crime clearance rates declined in both states before legalization.

The study authors wrote, “Our models show no negative effects of legalization and, instead, indicate that crime clearance rates for at least some types of crime that are increasing faster in states that legalized than in those that did not.”

There were no other major public policy changes in these states at the time, which indicates that marijuana legalization played a role in law enforcement being able to focus more time on violent crime.

The authors concluded that, “We think the argument that legalization did in fact produce a measurable impact on clearance rates is plausible.”

Other types of crimes have also decreased in frequency, such as property crimes. Colorado saw a significant decrease in property crimes following legalization.

The authors wrote, “The clearance rate for these two offenses increased dramatically post-legalization. In contrast, national trends remained essentially flat.”