Transcript for Colorado Police Facing More Stoned Drivers
You've seen drunk drivers, but tonight here, a different kind. This year, Colorado and Washington becoming the first states to legalize recreational maern. And now that new concern on the roads. ABC's Clayton sandelltrn paul with the police. Reporter: It's the new challenge for cops patrolling Colorado's highways. Any marijuana tonight? I did have some of that, sir. Okay. Reporter: Drivers getting behind the wheel, stoned. Hey, you know why I stopped you? No. All right man, you are driving all over the place, okay? Hey, man. How much marijuana have you smoked tonight? Reporter: Police say the signs of drunk driving can be obvious. But judging marijuana impairment is tougher. Just one joint? Yes, sir. Reporter: For now, police are relying on standard roadside tests. Foul local willow with your eyes and eyes only. Reporter: There is no breathalyzer test and results from drawing blood can take weeks. Plus, seasoned users are less impaired with more in their blood and newer users are going to be more impaired with less in their blood. This year, Colorado state troopers have written nearly 230 citations for driving high. Compared to over 3,100 for alcohol. People need to know it's a significant problem. Reporter: Dr. Christian thurstone and colleagues found that as marijuana has become widely available in Colorado, the number of drivers testing positive after fatal crashes doubled. Valorie Walton is recovering from serious injuries after she was hit by a driver police say was high. It makes me upset because they don't realize that it does affect them. Reporter: But different dud cities disagree on whether stoned drivers are actually causing more crashes. This driver failed his roadside test. Red eyes. Put your hands behind your back. Reporter: And now could be headed for a different kind of joint. Clayton Sandell, ABC news, Denver.
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