Lawmakers on the House Energy and Commerce Committee held a hearing last week on the dangers of drug-impaired driving.

There is growing concern in Congress over the issue as data from the Governors Highway Safety Association (GHSA) and the Foundation for Advancing Alcohol Responsibility finds that accidents from drugged driving have been on the rise over the last 10 years.

A recent report showed that 44 percent of fatally injured drivers tested positive for drugs in 2016. That number is up from 2006, when just 28-percent of fatally injured drivers were drug-positive.

But lawmakers also pressed for more information about the problem.

While the trend appears to be alarming, Rep. Jan Schakowsky (D-Ill.) raised questions the statistics from the GHSA and the Foundation for Advancing Alcohol Responsibility.

“While this statistic, of course, raises concern, I have questions and concerns about the methodology and accuracy of this statement,” Schakowsky said.

She pointed out that there is no nationally accepted way of testing the drug impairment level of drivers.

“Alcohol continues to cause more deaths than drugs,” Schakowsky said.

Colleen Sheehy-Church, the President of Mothers Against Drunk Driving (MADD), who testified at the hearing, agreed.

“The truth is that we do not know how many people are killed each year due to drug-impaired driving,” said Sheehy-Church, whose son was killed by a driver who was under the influence of both alcohol and drugs.

MADD, founded in 1980, advocates against drunk driving. The group says focusing on that problem will also help reduce drug-impaired driving.

Lawmakers and experts also debated the impact of marijuana legalization on the issue. Recreational marijuana is now legal in nine states.

“With the prevalence of marijuana legalization — recreation and medicinal — it is critical that more work be done to understand impairment," Sheehy-Church.

"We agree with the recent AAA [American Automobile Association] study, which states, a .08 [blood alcohol content] equivalent may not be possible with marijuana. But we still must better understand how marijuana impairment influences driving behaviors,” she added.

Republican Reps. Larry Bucshon (Ind.) and Leonard Lance (N.J.) both spoke out against marijuana legalization in their home states during the hearing.

“I personally oppose [legalization] based on medical grounds,” said Bucshon, a former surgeon.

Dr. Robert DuPont, president of the Institute for Behavior and Health, gave lawmakers suggestions to help prevent drug-impaired driving.

DuPont recommended that states implement a zero-tolerance policy for drivers under the age of 21, hand down the same penalties for drugged driving as for drunk driving and impose additional penalties for those who are impaired by multiple substances.

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