Collision claims are higher than expected in the first three states that permitted recreational use of marijuana for adults 21 years old and older, according to the Highway Loss Data Institute (HLDI).
The three states with legalized marijuana – Colorado, Oregon, and Washington – have had a 3 percent rise in collision claims. The largest increase was in Colorado, the first state to legalize marijuana in January 2014.
During its analysis, HLDI also examined collision claims in adjacent states that have not legalized marijuana use and compared the data. Claims between January 2012 and October 2016 were examined.
A separate study by the University of Texas at Austin found that fatal crashes in two states with legalized recreational marijuana use rose, but not significantly.
The study, published in the American Journal of Public Health, examined fatal crash rates in Colorado and Washington between 2009 and 2015.
During that time frame, 77 crash fatalities were linked to marijuana use. This is a 2.7 percent increase in fatalities and is statistically insignificant.
While the number of lower speed crashes increased, the number of fatal accidents were a small percentage.
“Together, these studies are consistent and support the conclusion that crashes have increased in states that have legalized the recreational use of marijuana,” Adrian Lund, Insurance Institute for Highway Safety-HLDI president, said.