Teens who drive under the influence or ride with a driver who is put themselves at risk.

Today’s teens face many challenges when trying to drive safely, whether it’s distracting texts or loud car companions. But many teens also report getting behind the wheel after drinking or using marijuana, or getting in the car with a driver who’s under the influence, adding yet another obstacle on the road to safety.

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In a study of more than 300 college students from two different Washington universities published in the JAMA Pediatrics, researchers from the University of Washington, Seattle, found that among students who had used marijuana, almost 44 percent of males and 9 percent of females reported driving after using the substance. Driving after alcohol use was less common, with 12 percent of males and almost 3 percent of females reporting driving after drinking.

But as many know, getting into a car with a driver who is under the influence can be just as dangerous as driving after using substances yourself. More than 51 percent of males and nearly 35 percent of female students reported getting in a car with a marijuana-using driver, and nearly 21 percent of males and 12 percent of females reported getting into a car with a driver who had had a drink.

Teens already have a greater risk of dying in an alcohol-related crash than adults, according to the National Highway Traffic Safety Administration (NHTSA). Even though teens and most college students are under the minimum drinking age (21 years) in every state, among 15- to 20-year-old drivers involved in fatal crashes in 2006, 31 percent of those drivers who died had been drinking, the NHTSA reports. 

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“Driving after marijuana use is not a new issue and has been a focus of study sine the 1980s,” writes Mark Asbridge, of Dalhousie University in Nova Scotia, in an editorial published alongside the study. Three observations can be drawn from extensive research on driving after marijuana use, Asbridge writes.

“First, in many jurisdictions, the prevalence of driving after marijuana use has risen in recent years. Second, driving after marijuana use is particularly problematic for younger populations, in which observed rates are considerably higher than in adults,” Asbridge writes. “Finally, it is apparent that, in certain populations, rates of driving after marijuana use parallel and sometimes surpass rates of drinking and driving.”

“Driving and riding after marijuana use is common among underage, marijuana-using college students. This is concerning given recent legislation that may increase marijuana availability,” the study authors conclude. As legislation on marijuana legalization moves forward, states will have to grapple with the issue of impaired driving.

And today’s teens have the added distractions of texts and social media apps. Five seconds is the average time your eyes are off the road when you text, and at 55 miles per hour on the highway—and let’s be honest, few adhere to that speed limit 100 percent of the time—that’s enough time to cover the length of a football field, reports Stop The Texts, Stop the Wrecks, a safe driving awareness campaign. 

“Distracted driving is the number one killer of American teens. Alcohol-related accidents among teens have dropped. But teenage traffic fatalities have remained unchanged, because distracted driving is on the rise,” reports Stop The Texts, Stop the Wrecks, from a 2007 Children’s Hospital of Philadelphia/State Farm study.

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The researchers found that many of the students they studied were aware of the risks involved in driving under the influence, but not all of them heeded the warnings.