Cannabis plants are housed at a Colorado seed developer's facility in November 2014. (Denver Post file)

More marijuana links in Utah traffic fatalities, but impairment a sticking point

Number of fatal car wrecks in Utah in which drivers tested positive for marijuana has more than doubled in the last three years

SALT LAKE CITY — Utah officials say the number of fatal car wrecks in Utah in which drivers tested positive for marijuana has more than doubled in the last three years, according to annual report from the state’s Department of Public Safety.

An annual report from the department found that the number of fatal crashes involving drivers testing positive for marijuana rose from 11 in 2012 to 38 in 2015, or an increase from 6 percent of crashes to 15 percent, The Deseret News reported.

The percentage of drivers in fatal crashes who are tested for drugs has increased from 42 percent in 2011 to 62 percent in 2015, according to the report.

Analysts say the uptick in marijuana-related crashes may be tied to legalization in nearby states. “Regardless of the cause, we’re very concerned about it,” said Utah Highway Patrol Sgt. Christian Newlin, who supervises the office’s breath testing and drug recognition programs.

Christine Stenquist, the executive director of Together for Responsible Use and Cannabis Education, said the data are compelling, but that the correlation doesn’t necessarily imply a strict causation. Marijuana, unlike alcohol, doesn’t have a known point at which a driver becomes impaired, she said. Also traces of marijuana can be found in someone’s blood days or weeks after use — long after it has stopped being psychoactive.

Even if marijuana is detected in someone’s blood, “it’s a huge challenge trying to figure out when someone is impaired,” Newlin said.

A report by the AAA Foundation released Tuesday found that traffic fatalities involving drivers in Washington where marijuana was involved had doubled between 2013 and 2014. Marijuana became legal in the state in 2012. The study also found that it was hard to say whether marijuana caused any of the crashes because the substance stays in the bloodstream for so long and because a number of drivers who tested positive for THC also tested positive for other drugs or alcohol.

Lawmakers agreed on a legal blood-alcohol concentration limit of 0.08 percent “because there were tests done,” Stenquist said.

“We have to get to that point with medical cannabis,” she said. “We have to get to the point to say this has medicinal viability. We need to research that a little more and figure out what that means.”

The National Highway Traffic Safety Administration conducted the first large-scale case-control study on the effects of marijuana on vehicle safety and found no association between testing positive for THC and crash risk.