Collision Claim Frequencies About 3 Percent Higher Overall
A new study says there is a definite link between legalized marijuana use and increased car cashes.
Legalized recreational marijuana use in Colorado, Oregon and Washington has resulted in collision claim frequencies that are about 3 percent higher overall than would have been expected without legalization, according to the study by Highway Loss Data Institute.
Colorado and Washington were the first states to legalize recreational marijuana for adults age 21 and older with voter approval in November 2012. Retail sales began in January 2014 in Colorado and in July 2014 in Washington. Oregon voters approved legalized recreational marijuana in November 2014, and sales started in October 2015.
New Mexico has legalized pot for medical uses, but attempts to legalize marijuana in the state in recent years have failed.
The HDLI’s study said that although there is evidence from simulator and on-road studies that marijuana can cause a deterioration in driving performance, researches haven’t been able to definitively connect pot use with an increase in car crashes.
But the HLDI study analyzed crash claim data in neighboring states as additional controls to examine the collision claims experience of Colorado, Oregon and Washington before and after law changes. Control states included Idaho, Montana, Nevada, Utah and Wyoming, plus Colorado, Oregon and Washington prior to legalization of recreational use.
“The combined-state analysis shows that the first three states to legalize recreational marijuana have experienced more crashes,” said Matt Moore, senior vice president of HLDI. “The individual state analyses suggest that the size of the effect varies by state.”
Colorado saw the biggest estimated increase in claim frequency compared with its control states, the study said. After retail marijuana sales began in Colorado, the increase in collision claim frequency was 14 percent higher than in nearby Nebraska, Utah and Wyoming. Washington’s estimated increase in claim frequency was 6 percent higher than in Montana and Idaho, and Oregon’s estimated increase in claim frequency was 4 percent higher than in Idaho, Montana and Nevada
“The combined effect for the three states was smaller but still significant at 3 percent,” Moore said. “The combined analysis uses a bigger control group and is a good representation of the effect of marijuana legalization overall. The single-state analyses show how the effect differs by state.”
In addition to Colorado, Oregon and Washington, five other states and Washington, D.C., have legalized marijuana for all uses, and 21 states have comprehensive medical marijuana programs as of June. An additional 17 states permit limited access for medical use. Marijuana is still an illegal controlled substance under federal law.
“Worry that legalized marijuana is increasing crash rates isn’t misplaced,” said David Zuby, executive vice president and chief research officer of the Insurance Institute for Highway Safety. “HLDI’s findings on the early experience of Colorado, Oregon and Washington should give other states eyeing legalization pause.”