“Our results are consistent with theories that predict that marijuana legalization will displace illicit criminal organizations and decrease crime.”

Two economists affiliated with the Philadelphia Federal Reserve looked at the effects of marijuana legalization on crime by studying the effects of cannabis dispensaries on localized crime rates. The study’s results, published in August in the journal Regional Science and Urban Economics, found that marijuana or cannabis dispensaries are associated with a 19% reduction in average crime rates in the local surrounding area.

The study’s authors, Jeffrey Brinkman and David Mok-Lamme, looked at legal retail dispensary locations in Denver, Colorado and their effects on neighborhood crime as dispensaries opened up.

An abstract of the study states: “The results imply that an additional dispensary in a neighborhood leads to a reduction of 17 crimes per month per 10,000 residents, which corresponds to roughly a 19 percent decline relative to the average crime rate over the sample period. Reductions in crime are highly localized, with no evidence of spillover benefits to adjacent neighborhoods.

“Our results are consistent with theories that predict that marijuana legalization will displace illicit criminal organizations and decrease crime through changes in security behaviors or substitution toward more harmful substances. … Lastly, there is no evidence that increased marijuana use itself results in additional crime.”

Studies Repeatedly Show Benefits of Marijuana Legalization

Brinkman and Mok-Lamme’s findings are consistent with previous studies examining the effect of marijuana legalization on crime, as exemplified by the Reason Foundation’s brief, Does Legalizing Marijuana Reduce Crime? 

Citing numerous studies, the brief overviews how marijuana legalization leads to a reduction in opioid use and a reduction in marijuana-related crimes as well as other crimes including some property and violent crimes.

A 2014 study found that opioid overdoses were about 25% lower in states that had legalized medical marijuana. Similarly, a 2016 study and two 2018 studies found that states with legalized medical marijuana had lower rates of prescription painkillers and anxiety and depression drugs. The studies suggest that legal marijuana is being substituted for other illicit drugs.

In addition to Brinkman and Mok-Lamme’s study showing an overall reduction in neighborhood crime, a 2017 study titled, “Joint Culpability: The effects of medical marijuana laws on crime”  found that medical marijuana legalization was associated with reduced property crime rates in California.

“Some studies have found a relationship between heavy marijuana consumption by adolescents and subsequent violent behavior. However, most studies suggest that marijuana use does not lead to an increase in violent crime. Some more recent studies suggest that legalization might reduce violent crime,” writes Julian Morris, author of the Reason Foundation’s brief.

Included in those studies is a 2014 study which found that introducing legalized medical marijuana was associated with a reduction in the overall rate of “Part 1 offenses” which include homicide, rape, robbery, assault, burglary, larceny and auto theft.

According to Morris, “These effects vary by location, with reductions in property and violent crimes being most pronounced in locations close to the Mexican border due to the diminution of activities of Mexican drug trafficking organizations and affiliated gangs.”

“Medical marijuana legalization also appears to be associated with a reduction in drunk driving. The effects of legalization of marijuana for recreational use are less clear,” adds Morris.

Marijuana Legalization Status

While marijuana is still not legal on the federal level, 33 states plus Washington D.C. have passed some form of medical marijuana legalization. Additionally, eleven states plus D.C. have legalized recreational marijuana.

On December 20, 2018, President Trump signed the 2018 Farm Bill which removed hemp from the Controlled Substances list, effectively ending the federal prohibition of non-psychoactive hemp and CBD related products. Hemp was instead moved under the jurisdiction of the Department of Agriculture, thus, treating it as any other agricultural commodity.

With over 66% of Americans supporting legalized marijuana in one form or another and 94% supporting medical marijuana, marijuana legalization is rapidly spreading across the country and the U.S. could soon follow in Canada’s footsteps of legalizing both medical and recreational marijuana at the federal level.