The Governors Highway Safety Association is releasing a study on drug-impaired driving and some media reports suggest drugged driving has overtaken drunk driving in terms of traffic fatalities.

J.T. Griffin, chief government affairs officer for Mothers Against Drunk Driving, says that’s not the case in Iowa or nationwide.  “With the new report coming out, we just wanted to remind the public that there is still a lot of unknowns about drug-impaired driving, but we know a lot about drunk driving and we know that it is the cause of one-third of all traffic deaths,” Griffin says. “That makes it the biggest killer on the roadways.”

In the past few years, there’s been a spike in traffic deaths, which Griffin attributes to the opiod abuse epidemic and to more states legalizing marijuana. He says it’s clear drugged driving is a serious problem, but there’s still a dire need for more study to clarify.

“We don’t have good statistics, we don’t have good data on exactly what the problem with drugged driving is,” Griffin says. “We don’t have impairment levels with regard to marijuana like we do with alcohol, so it is very difficult to figure out the scope of the problem.”

In 2015, MADD expanded its mission to include drug-impaired driving with a commitment to continue serving victims of both drunk- and drugged-driving. In addition, MADD advocates for policies based on research and science to help prevent alcohol- and drug-impaired driving. Since MADD was founded in 1980, the number of drunk driving deaths has been cut in half, but further progress has slowed.

“Drunk driving is about a third of all highway deaths and right now, that’s about 10,000 people a year,” Griffin says. “While we’ve made good progress, we still have a long way to go and the number’s been stubborn. It’s been stuck at a third for quite a while.” A total of 320 people died in crashes on Iowa roadways in 2015 and of those, 78 involved alcohol, or 25 percent. The new report from the Governors Highway Safety Association indicates drugs were found in 43 percent of drivers tested in fatal crashes, compared to 37 percent in alcohol involved crashes.

MADD says it does not mean more crashes were caused by drugged driving than drunk driving as it’s not an apples-to-apples comparison on multiple levels.