When states make the use and retail sales of recreational marijuana legal, crash rates rise.
Injury and fatal crash rates jumped 6% and 4%, respectively, in California, Colorado, Nevada, Oregon and Washington following relaxation of marijuana laws compared with other Western states where recreational marijuana use was illegal. Insurance records showed a similar increase in collision claims after marijuana became legal.
“Our latest research makes it clear that legalizing marijuana for recreational use does increase overall crash rates,” David Harkey, president of the Insurance Institute and its affiliate, the Highway Loss Data Institute, said in a statement.
However, despite crash increases, research has been inconsistent regarding whether marijuana itself makes drivers more likely to crash. The latest Insurance Institute study, for example, which used data collected from more than 1,200 injured drivers in three emergency rooms in Denver, Colorado; Portland, Oregon; and Sacramento, California, showed no increased crash risk associated with the drug, except when combined with alcohol.
Previous tests conducted in simulators indicated that drivers who are high on marijuana react more slowly, find it harder to pay attention, have more difficulty maintaining their car’s lane position, and make more errors when something goes wrong than they do when they’re sober, the safety groups said. But the tests also indicated that marijuana-impaired drivers are likely to drive at slower speeds, make fewer attempts to overtake and keep more distance between their vehicle and the one ahead of them.
Legalization may be encouraging more people to drink and use marijuana together, a possible explanation for why crash rates have increased, according to the researchers.
Studies comparing the simultaneous use of alcohol