Vehicle crashes are up in states that have legalized recreational marijuana according to two new analyses of crash data by the Insurance Institute for Highway Safety and the Highway Loss Data Institute.
There is enthusiasm in Canada this week as it becomes the second country to legalize recreational marijuana. In the U.S., recreational cannabis is now legal in nine states and the District of Columbia.
But with the wave of change comes new research linking legal cannabis with an increase in vehicle crashes.
“The likelihood of being involved in a collision in states with legalized marijuana is higher than neighboring states we used as controls,” said David Harkey, president of IIHS-HLDI.
The report analyzed insurance and police data from some of the first states to legalize recreational cannabis; Colorado, Washington, Oregon and Nevada.
In those states, crashes are up by as much as six percent compared with states where marijuana is illegal.
“We do not want to see marijuana reach the same level of destruction on our roadways as we have seen with alcohol,” said Harkey.
While drunk driving is widely considered taboo, the same stigma may not exist for driving high.
In a Washington Roadside survey, drivers who tested positive for THC were less likely to agree that marijuana impairs driving.
14-percent of drivers with marijuana in their system had a child in the car.
“You shouldn’t be behind the wheel regardless of what the substance is,” Harkey stated.
Driving under the influence of marijuana is illegal in all 50 states, but determining impairment continues to be a challenge.