A study by researchers at Washington State University has found evidence of “demonstrable and persistent benefit” to police departments’ effectiveness in Washington and Colorado since the states voted to legalize cannabis in 2012.
Researchers used monthly FBI data to investigate crime clearance rates for the states from 2010 to 2015; crimes are normally considered “cleared” when a suspect is identified, arrested, and entered into the judicial system for prosecution.
“Our models show no negative effects of legalization and, instead, indicate that crime clearance rates for at least some types of crime are increasing faster in states that legalized than in those that did not.” — WSU researchers, via The Washington Post
Researchers looked at violent crime and property crime clearance rates — most specifically, burglary and vehicle theft — and found marked boosts after the states’ legalization laws took effect in comparison to the rest of the country.
“The clearance rate for these two offenses increased dramatically postlegalization. In contrast, national trends remained essentially flat.” — WSU researchers
The researchers noted that this data does not prove legalization is the direct cause of the changes in clearance rates. Other variables in police activity — such as new policing strategies or an increased use of overtime hours — could certainly have played a role. The study authors did note, however, that there were not any other major policy changes at that time in those states to account for the boosted police effectiveness.
“We think the argument that legalization did in fact produce a measurable impact on clearance rates is plausible.” — WSU researchers, in the study’s conclusion