Over the past decade, drinking and driving has been on the downswing, but drugging and driving has seen the opposite trend, increasing by 16 percentage points from 2006 to 2016, researchers found.
Roughly 44% of drivers who died in car crashes in 2016 were on drugs at the time; in 2006, only 28% were.
Marijuana was the substance that came up most often in post-mortem testing, with 38% testing positive for it. Around 16% came up for opioids and 4% for both.
“Too many people operate under the false belief that marijuana or opioids don’t impair their ability to drive, or even that these drugs make them safer drivers,” said GHSA Executive Director Jonathan Adkins.
“Busting this myth requires states to expand their impaired driving campaigns to include marijuana and opioids along with alcohol to show drivers that impairment is impairment, regardless of substance.”
But understanding the risks associated with impairment is complicated by the fact that the data doesn’t clarify whether the drugs actually led to the crash.
“Drugs can impair, and drug-impaired drivers can crash,” the report’s author, former National Highway Traffic Safety Administration official Dr. Jim Hedlund told NBC News.
“But it’s impossible to understand the full scope of the drugged driving problem because many drivers who are arrested or involved in crashes, even those who are killed, are not tested for drugs. Drivers who are drug-positive may not necessarily be impaired.”
Just over 50% of fatally injured drivers were tested for drugs or booze after they died.
Though police have aggressively worked to combat drunk driving for decades, it’s a little harder to crack down on drugged driving, as there’s no roadside breathalyzer for illicit substances and no commonly accepted measure of how much is too much.
“With alcohol, we have 30 years of research looking at the relationship between how much alcohol is in a person’s blood and the odds they will cause a traffic crash,” said AAA traffic safety director Jake Nelson, according to Sentinel Source. “For drugs, that relationship is not known.”