GALLOWAY TOWNSHIP, N.J. — Recreational marijuana has slowly begun to be accepted by society and legalized in a growing list of states across the U.S. in recent years. One of the biggest arguments for the legalization of marijuana is the potential for a significant drop in crime rates. Well, a study by researchers at several universities finds that crime statistics haven’t changed much in two U.S. states that legalized recreational marijuana use and sales.
The study, commissioned by a grant from the Crime and Justice Research Alliance, focused on Colorado and Washington, the two first states to legalize recreational marijuana, and looked specifically at property-related and violent crimes.
“In many ways, the legalization of cannabis constitutes a grand ongoing experiment into how a major public policy initiative does or does not accomplish its expected outcomes,” says first author Ruibin Lu, assistant professor of criminal justice at Stockton University, in a statement. “Given the likelihood of more states legalizing recreational marijuana, we felt it was important to apply robust empirical methods to parse out the effects of this action on crime in the first years after legalization.”
Previous research showed mixed results regarding how the legalization of cannabis affects crime rates, the types of crimes committed, etc. Consequently, politicians and political advocacy groups on both sides of the legalization debate have used these inconclusive findings to support their positions.
So, the research team for this study used more rigorous, quasi-experimental methods than previous researchers had employed. Colorado and Washington were chosen due to their status as the first states to legalize the growing, processing, and selling of marijuana for recreational use.
The research team compared monthly crime rates in Colorado and Washington to crime rates in 21 others states that haven’t legalized recreational or medicinal marijuana, using crime rate data from the FBI’s Uniform Crime Report from 1999 to 2016. The research team then calculated how crime rates changed in Colorado and Washington after legalization, and compared those stats to states that had not legalized marijuana.
The results revealed no statistically significant, long-term positive effects of recreational cannabis laws on violent and property crime rates in either state. They did, however, find a reduction in burglaries in Washington, but overall the results suggest that marijuana legalization has had minimal effect on major crimes in the two states.
In fact, the study actually noted an increase in property crimes in both Washington and Colorado immediately following the legalization of recreational marijuana. Aggravated assault cases also increased in Washington shortly after legalization legislation. But, all of these increases were short-term, and were not indicative of permanent increases in crime.
The study only focused on major crimes, so its authors caution they may have found different results regarding other types of crime.
“As the nationwide debate about legalization, the federal classification of cannabis under the Controlled Substances Act, and the consequences of legalization for crime continues, it is essential to center that discussion on studies that use contextualized and robust research designs with as few limitations as possible,” says co-author Dale W. Willits, assistant professor of criminal justice and criminology at Washington State University. “This is but one study and legalization of marijuana is still relatively new, but by replicating our findings, policymakers can answer the question of how legalization affects crime.”
The study is published in the journal Justice Quarterly.