Car accidents have spiked in the first three states to legalize recreational marijuana, as law enforcement and state lawmakers grapple with how to define marijuana-impaired driving and test drivers for marijuana. It is much more complex than enforcing laws against driving drunk, analysts said.
Colorado, Washington, and Oregon saw a combined 5.2% increase in the rate of police-reported car crashes after marijuana legalization, compared with neighboring states where marijuana is still illegal, according to researchers from the Highway Loss Data Institute, who compiled and analyzed data from the Insurance Institute for Highway Safety. The researchers also found that auto-insurance collision claims increased a combined 6% across all three states since legalization, compared with neighboring states.
Other organizations are voicing worry over the issue. The Washington Traffic Safety Commission said that the number of drivers involved in fatal crashes in the state who tested positive for THC, the psychoactive chemical in marijuana, more than doubled since 2013. Recreational sales of marijuana first occurred legally in Washington in 2014.
Helen Witty, president of Mothers Against Drunk Driving, said that “Drunk driving is still the No. 1 killer on our roads. … But drugged driving, as it’s legalized across this country, is a huge, emerging issue.”
Researchers said that policing against marijuana-impaired driving is difficult as there is no official legal definition of it, nor is there any recognized breathalyzer-like system for reliably detecting marijuana in a driver’s breath or blood. The presence of marijuana in blood also does not necessarily indicate impairment, and THC can disappear from the bloodstream in as little as a half-hour, making it difficult to capture incriminating evidence from even a driver who has consumed marijuana, said Staci Hoff, research director at the Washington Traffic Safety Commission.