As legalization efforts first took off last decade, many opponents stoked fears that legal cannabis would lead to many problems. One of those potential problems, they argued, involved people using cannabis and then getting behind the wheel and causing fatal accidents.

A new study from the University of Minnesota has found that, like other long-held beliefs about marijuana, this is not the case. In fact, it’s just the opposite in some states.

Published recently in the academic journal Traffic Injury Prevention, the study found no correlation between legalizing cannabis for medical or recreational use and an increase in fatal traffic accidents, including those involving pedestrians.

Washington and Oregon saw an immediate drop in all fatal car accidents after medical cannabis became legal. “Overall findings do not suggest an elevated risk of total or pedestrian-involved fatal motor vehicle crashes associated with cannabis legalization,” the researchers wrote.

Researchers Looked at Accidents in Three States

Researchers at the University of Minnesota looked at crash data between 1991 and 2018 for Colorado, Oregon and Washington kept in the Fatality Analysis Reporting System (FARS). The federal National Highway Traffic Safety Administration has offered the FARS data since 1975. It includes data from all 50 states, the District of Columbia and Puerto Rico.

Experts consider the database the most accurate on fatal crash data available. Crashes included in the database must involve a vehicle traveling on a road open to the public and result in the death of a vehicle occupant or nonoccupant within 30 days of the crash.

To better measure crash rates, researchers compared data from the three legal states to five states with no legalized cannabis. They calculated monthly fatal crashes, both those that did and did not involve a pedestrian. They then calculated a death rate from these accidents per 100,000 people.

Using this data, they found no increase within the states, nor did the legal cannabis states have a rate of fatal traffic deaths higher than what researchers found in control states.

Study Is Consistent With Previous Findings

The University of Minnesota’s study is consistent with the findings of previous studies that looked for any association between legalizing cannabis and an increase in car accidents, according to research done by NORML.

For example, a 2019 study from the University of California – Irvine found that medical marijuana legalization in California led to a sustained decline in traffic fatalities. And a 2016 student from Columbia University and the University of California – Davis associated medical cannabis legalization with a reduction in traffic fatalities involving younger people.