Researcher warns of more ‘driving while high’ deaths

Phillip Drum sees his sister’s death in July 2012 as the proverbial canary in the coal mine — a warning of the dangers of marijuana use and driving.

Rosemary Tempel, a 56-year-old trauma nurse, died when a driver who was allegedly under the influence of marijuana collided head-on with Tempel’s car, causing an eight-vehicle crash in Seattle.

Charges were filed against the driver the day before Washington voters legalized marijuana for recreational use. The state already allowed medicinal uses of marijuana.

“We could not go to the media to warn the public in the state of Washington that you got a problem coming your way,” said Drum, a pharmacist in Martinez, Calif. “You’re going to have more marijuana drivers.”

New traffic crash data suggest that the number of deaths while driving “high” is increasing in the United States — and it might get worse as more states legalize marijuana.

“It could be a real tidal wave of problems,” said Al Crancer Jr., a retired National Highway Traffic Safety Administration researcher in Moraga, Calif. “So many people think it is just a very harmless drug.”

The numbers suggest otherwise when it comes to drugged driving. Marijuana is already the most frequently detected drug, other than alcohol, found in drivers in wrecks, Crancer said.

“It’s prevalent enough that it is something we always look for,” said Sgt. Bill Mahoney, a supervisor with the Kansas City Police Department’s accident investigation section.

Nationally, 15 percent of drivers in fatal crashes in 2014 who had been tested for drugs had marijuana in their systems, Crancer said.

In states where marijuana is legalized, the percentage was higher. In California, a medical marijuana state, and Colorado, a state that allows medical and recreational marijuana use, 19.5 percent of drivers in fatal wrecks tested positive for marijuana.

In Washington, it was 27 percent — just shy of the 29 percent of drivers who were driving drunk.

“As far as drugged driving statistics, we are still in our infancy of getting our data where we want it to be,” said Glenn Davis, highway safety manager for the Colorado Department of Transportation.

Colorado is seeing more people with drugs in their systems, Davis said. But the marijuana data don’t indicate whether the driver was impaired or had just used the drug recently.

Marijuana use in Colorado isn’t new. What is, officials said, is its legal availability and the lack of taboo surrounding it.

“You can legally consume and possess marijuana to a certain degree, but driving under the influence of it, just like alcohol and just like any prescription painkiller or any other drug, is still against the law and it will continue to be against the law,” said Trooper Josh Lewis, public information officer with the Colorado State Patrol.

“We want people to understand that you can be charged just like alcohol and face the same consequences for it.”

While a national threshold has been established for when drivers are legally drunk — a blood alcohol level of 0.08 percent — a similar limit has not been established for other drugs like marijuana, said Sgt. Christopher Bentch, DUI section supervisor with the Kansas City Police Department.

Some states have set limits. In Colorado, for example, authorities can prosecute people for driving under the influence if they have 5 nanograms of active THC — the chemical primarily responsible for the high in marijuana — in their blood. Drivers with lower levels can be arrested if they show signs of impairment, just as in cases in which drivers have been drinking.

“Quite honestly, we only need to prove two things — you were driving and you were impaired,” Bentch said. “If we make a case on our observations, which in many cases we can, we arrest them and take it to court and see how we do.”

There hasn’t been a noticeable uptick in DUI cases based on marijuana use, said Dan Portnoy, an assistant Jackson County prosecutor.

“The cases where we see positive tests for marijuana, we treat them the same as we treat alcohol,” Portnoy said. “If we can prove that marijuana impairment contributed to the driving, we can meet our elements under the law, then we will prosecute them that way.”

Marijuana cases are complicated because a driver could test positive for the drug even if it’s not actively affecting the ability to drive. Depending on the tests being used, traces of marijuana can be detected in blood samples weeks after use, according to highway safety administration research.

Unless tested for delta 9-THC, there’s no way to identify impairment, said Christopher Long, director of Forensic & Environmental Toxicology Laboratories at the St. Louis University School of Medicine.

The problem is that the body metabolizes the ingredient in a few hours, making it necessary for law enforcement officials to get blood samples quickly.

“If you want to sit in your backyard and get stoned to where you have to grab the grass to keep from falling off the earth, I really don’t care,” Long said. “But if you get in the car and hurt somebody else, that’s a different story.”

This story was originally published December 29, 2015 at 5:11 PM with the headline "Researcher warns of more ‘driving while high’ deaths."