Leesburg police and the Virginia State Police conduct a sobriety checkpoint in September 2005. (Leesburg Police Department)

report suggesting that drivers killed in crashes are more likely to be on drugs than drunk is getting pushback from a surprising direction — other traffic-safety advocates.

A week after a report suggesting that drug-impaired driving is moving to the fore of concerns in traffic safety, Mothers Against Drunk Driving (MADD) jumped in Monday to express concern that the report could lead the public to believe the country has turned the corner on drunk driving. There is still much work to do, MADD officials said.

“There is no way you can say drugs have overtaken alcohol as the biggest killer on the highway,” J.T. Griffin, chief government affairs officer at MADD, said Monday. “The data is not anywhere close to being in a way that would suggest that … We’re doing a lot of good things on drunk driving, but the public needs to understand this problem is not solved.”

MADD officials also questioned the methodology of the research in the report, noting that there is no scientifically agreed level of impairment with drugs such as marijuana. There is also no uniform test, roadside or otherwise, to determine such a level.

The Governors Highway Safety Association (GHSA), citing federal statistics, last week issued an update of a comprehensive 2015 report saying that 43 percent of drivers tested in fatal crashes in 2015 had used a legal or illegal drug, higher than the 37 percent who tested above the legal limit for alcohol. The report comes as 29 states, along with the District of Columbia, have moved to legalize medical marijuana, according to the National Conference of State Legislatures. Some have also lifted penalties on recreational use. What’s more, the use of opioids has become epidemic in some parts of the country.

In releasing its findings, the GHSA — whose report  drew on data from the National Highway Traffic Safety Administration’s (NHTSA) Fatal Analysis Reporting System (FARS) — urged states to step up efforts to train law enforcement to spot and arrest impaired drivers who have been using marijuana, opioids or other drugs.

MADD — which altered its mission in 2015 to include the fight against drug-impaired driving — found itself on Monday emphasizing limitations in the GHSA report. MADD officials said tests that are available to analyze drug and alcohol use are so different as to be unreliable when comparing the two using FARS data. MADD officials also recoiled from the possibility that many would read the GHSA report and conclude that more fatalities are caused by drug-impaired drivers than those impaired by alcohol.

To some, the report smacked of an attempt by the makers and purveyors of booze to shift the conversation. That’s because the GHSA report was also underwritten by the Foundation for Advancing Alcohol Responsibility, whose members include makers of alcoholic beverages such as Bacardi USA; Brown-Forman, which produces Jack Daniel’s whiskey; and Constellation Brands, whose labels include Corona beer.

“I don’t know what their motives are,” Griffin said. “But I do know this: I know alcohol is a drug, and that’s something a lot of people don’t like to talk about, but it is. It impairs the mind. And I know alcohol causes many more deaths than drugs do. We can talk about an increase in drug-impaired driving. But it is not accurate in any way to say drugs have overtaken alcohol in terms of deaths on our highways.”

James Hedlund, an independent consultant who wrote the report for the GHSA, said MADD’s criticism  is unwarranted. Both sides are, after all, on the same page, even if it’s also possible that MADD jumped into the fray for fear that the spotlight might shift from drunk driving.

“Nowhere in the report does it say that more crashes are caused by drugged drivers than by drunk drivers,” Hedlund said. “What it says is what the data say: It says that there are more dead drivers with known test results for drugs than there are dead drivers that are positive for alcohol. And that’s a straightforward fact. It doesn’t say the drug caused the crash. It doesn’t even say the alcohol presence caused the crash.”

Hedlund also agreed that much more research must be done about impaired driving involving drugs. He said his report also makes clear that the work is going to be more complicated than the research that developed a consensus on alcohol, including the 0.08 percent blood alcohol level for impairment and blood and breath tests to determine whether that limit has been surpassed. And he acknowledged that research is still unsettled on the impairment level of marijuana or abilities to test for it. THC, the active ingredient in marijuana, dissipates from the bloodstream quickly, yet traces of the drug may remain in a person’s body for weeks, he said.

“The point is that the information available about drugs is far less certain than the information available for alcohol,” Hedlund said.

Over at NORML, which has spent years seeking to decriminalize marijuana, officials cited other federal highway data to make the point that  GHSA report merely reflected increased detection that doesn’t suggest any direct connection to crashes.

Paul Armentano, the organization’s deputy director, noted that over the past two decades, the number of crashes have been falling, while at the same time numerous states have amended their marijuana laws. He also cited a NHTSA analysis of odds ratios that while drivers who have alcohol in their systems are four times more likely to have a crash, drivers who are THC-positive have no elevated risk after adjusting for age and gender.

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