As legal marijuana spreads and the opioid epidemic rages on, the number of drugged drivers killed in car crashes is rising dramatically, according to a report released today.
Forty-four percent of fatally injured drivers tested for drugs had positive results in 2016, the Governors Highway Safety Association found, up more than 50 percent compared with a decade ago. More than half the drivers tested positive for marijuana, opioids or a combination of the two.
"These are big-deal drugs. They are used a lot," said Jim Hedlund, an Ithaca, New York-based traffic safety consultant who conducted the highway safety group's study. "People should not be driving while they're impaired by anything and these two drugs can impair you."
Nine states and Washington, D.C., allow marijuana to be sold for recreational and medical use, and 21 others allow it to be sold for medical use. Opioid addiction and overdoses have become a national crisis, with an estimated 115 deaths a day.
States are struggling to get a handle on drugged driving. Traffic safety experts say that while it's easy for police to test drivers for alcohol impairment using a breathalyzer, it's much harder to detect and screen them for drug impairment.
There is no nationally accepted method for testing drivers, and the number of drugs to test for is large. Different drugs also have different effects on drivers. And there is no definitive data linking drugged driving to crashes.
"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 Jake Nelson, AAA's traffic safety director. "For drugs, that relationship is not known."
Another problem is that drivers often are using more than one drug at once. The new study found that about half of drivers who died and tested positive for drugs in 2016 were found to have two or more drugs in their system.
Alcohol is also part of the mix, the report found: About half the dead drivers who tested positive for alcohol also tested positive for drugs.
Drug Testing Varies
More than 37,000 people died in vehicle crashes in 2016, up 5.6 percent from the previous year, according to the National Transportation Highway Safety Administration.
Using fatality data from the federal agency, Hedlund, the governors' highway safety group's consultant, found that 54 percent of fatally injured drivers that year were tested for drugs and alcohol. Of those who had drugs in their system, 38 percent tested positive for marijuana, 16 percent for opioids and 4 percent for both. The remaining 42 percent tested positive for a variety of legal and illegal drugs, such as cocaine and Xanax.
That means more than 5,300 drivers who died in fatal crashes in 2016 tested positive for drugs, Hedlund said. Those numbers don't include all drivers killed in crashes or those who drove impaired but didn't have a crash.
Driver drug testing varies from state to state. States don't all test for the same drugs or use the same testing methods.
"A lot of the tools we developed for alcohol don't work for drugs," said Russ Martin, government relations director for the highway safety group. "We don't have as clear a method for every officer to conduct roadside tests."
Police who stop drivers they think are impaired typically use standard sobriety tests, such as asking the person to walk heel to toe and stand on one leg. That works well for alcohol testing, as does breathing into a breathalyzer, which measures the blood alcohol level.
But these standard sobriety tests don't work for drugs, which can only be detected by testing blood, urine or saliva. Even then, finding the presence of a drug doesn't necessarily mean the person is impaired.
With marijuana, for example, metabolites can stay in the body for weeks, long after impairment has ended, making it difficult to determine when the person used the drug.
States have dealt with drugged driving in different ways. In every state it is illegal to drive under the influence of drugs, but some have created zero tolerance laws for some drugs, whereas others have set certain limits for marijuana or some other drugs.
That creates another challenge because policymakers are trying to make changes that aren't necessarily based on research, said Richard Romer, AAA's state relations manager.
"The presence of marijuana doesn't necessarily mean impairment," Romer said. "You could be releasing drivers who are dangerous and imprisoning people who are not impaired."
In Colorado, the first state to legalize recreational marijuana, there were 51 fatalities in 2016 that involved drivers with THC blood levels above the state's legal limit, according to the state department of transportation. THC is the main active ingredient in marijuana, and causes the euphoria associated with the drug.
An online survey in April by the department found that 69 percent of pot users said they had driven under the influence of marijuana at least once in the past year and 27 percent said they drove high almost daily. Many recreational users said they didn't think it affected their ability to drive safely.
In Washington state, a 2016 report by the AAA Foundation for Traffic Safety found that fatal crashes of drivers who recently used marijuana doubled after the state legalized it.
The governors' highway safety group is recommending that states offer advanced training to a majority of patrol officers about how to recognize drugged drivers at the roadside.
Officers in some states already are using a battery of roadside tests that focus on physiological symptoms, such as involuntary eye twitches, pulse rate and muscle tone, to determine whether a driver is impaired by drugs. And at the police station, some officers trained as drug examiners do a more extensive series of tests to identify the type of drug.
The safety group also wants states to launch a campaign to educate the public about how drugs can impair driving and work with doctors and pharmacists to make patients aware of the risks of driving while using prescription medications such as opioids.
And it is calling on states and the federal government to compile better data on drugged driving, including testing all drivers killed in crashes for drugs and alcohol.
"Not every driver in a fatal crash is tested. And plenty of drivers out there haven't crashed and haven't been tested," Martin said. "We have good reason to believe there are more drug-impaired drivers out there than the data shows."