Insurers: Preliminary data shows legalization increases crashes

It’s not all fun and games in the states that have legalized marijuana for recreational purposes. As you might expect, a good deal of responsibility is required when using legal weed — especially when you will be driving. Unfortunately, it appears that legalizing cannabis may have caused the car crash rate to increase by as much as 10 percent.

That’s based on preliminary numbers from a white paper by the Insurance Information Institute (III). The group pointed to an October 2018 study of insurance claims data by the Highway Loss Data Institute. In that study, collisions claims were up 12.5 percent in Colorado and 9.7 percent higher in Washington state than in surrounding states that didn’t legalize recreational weed. That data was based on collision claims between January 2012 and October 2017.

“When a state legalizes marijuana, more people use the drug,” the III says in its white paper. “More people using marijuana is associated with more people driving with THC in their systems.” That said, it stopped short of concluding that more people are driving impaired by THC.

A separate study by the Insurance Institute for Highway Safety (IIHS) considered collisions that were reported to the police between 2012 and 2016 — just before and after retail sales started in Colorado, Washington and Oregon. The IIHS combined the data from the three states and compared it to several neighboring states where recreational marijuana was not legalized. The researchers found an increase in crashes of 5.2 percent.

Another study, this one by the National Bureau of Economic Research, looked at fatal accidents in which one or both drivers tested positive for marijuana use. After the drug was legalized in Colorado and Washington, the number of such accidents increased. In Colorado, the number was up by 9 percent; in Washington it was 28 percent.

That said, merely testing positive for marijuana does not necessarily indicate the driver was actually impaired. Furthermore, law enforcement may have increased testing for marijuana since legalization, which would likely increase the total number of positive results.

Ultimately, increased use of marijuana due to legalization may increase crashes

The Insurance Information Institute’s white paper may not make a direct connection between marijuana legalization and an increase in crashes caused by marijuana impairment. It does, however, suggest that legalization probably encourages more people to use the drug, which could easily translate into an increase in impaired drivers.

Here in Colorado, we’re at the forefront of the question. Will people avoid driving while they’re under the influence of THC? It would be terrific if the answer were always yes, but there will likely be a fair number of accidents due to THC impairment.