Canadian researchers have discovered smoking marijuana three hours before driving can more than double a driver's chance of being involved in a serious crash. The study examined data collected from 49,111 victims who had been seriously injured or died in an accident. Researchers specifically looked at cases where tetrahydrocannabionol, the active compound in marijuana, was found in the victims' blood stream but where other drugs and alcohol were absent. The study also evaluated instances where the driver admitted to smoking within three hours of the crash. The findings demonstrate that, while those who drive under the influence of alcohol are still more likely to be involved in a collision than their pot-smoking counterparts, marijuana significantly impairs an individual's ability to safely operate a vehicle.


The study did not note precise levels of THC present in each instance, though as CBC News reports, other research has proven a positive link between the higher crash likelihood and elevated THC levels.

Law enforcement agencies are currently struggling to effectively test for THC impairment during roadside stops. Unlike blood-alcohol levels, which can be easily tested for using a breath test, THC is harder to detect. As a result, most agencies have adopted a zero-tolerance policy.

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    • 1 Second Ago
      Dark Gnat
      • 2 Years Ago
      It was really cool of the Chrysler UAW guys to pose for this picture.
      • 2 Years Ago
      stupid people triple the risks of a serious crash. put a law on that!
      Sean Flanagan
      • 2 Years Ago
      The collection of "I [used to] drive high" comments on this are startling. Same thing I hear from drunk drivers—"I drive home from the bar all the time, never got in an accident."—and people taking Rx that clearly state "do not drive or operate machinery". How about if you're using/taking/whatevering a substance that affects the brain, no matter what it is, you don't drive?
      • 2 Years Ago
      With everyone on here admitting to be high while driving, I no longer wonder why everyone seems to be high while driving...because apparently they are high while driving...
      Ernie Mccracken
      • 2 Years Ago
      • 2 Years Ago
      They needed a study to figure that one out?
      • 2 Years Ago
      This was common sense, was it not?
      • 2 Years Ago
      Marijuana? Are we really talking about Marijuana here? I'll tell you one thing; Weed is for wussies. -Whitney Houston
      • 2 Years Ago
      legalize it after there is a way to test it for a dui. and then increase the dui penalties.
      • 2 Years Ago
      hard to drive when your reaching for that bag of nacho doritos..
        • 2 Years Ago
          • 2 Years Ago
          Pot is only a stepping stone if you let it and making a blanket statement saying it's a stepping stone to harder drugs is just plain ignorant! Look at Amsterdam in Holland, it is legal, it's taxed and controlled and their country has not fallen apart AND they have less crime per capita than the United States. I know a lot of people, and I mean a lot of people, that started smoking pot 25 years ago and only one of them ever moved on to stronger drugs and had a problem. The rest of them either stopped smoking pot or only do it once in a great while. Meanwhile I know several alcoholics and one meth-head, none of whom ever smoked pot that I know of.
          • 2 Years Ago
          • 2 Years Ago
          Not true. I'm content with Mary Jane, no desire to do anything else. I'd do cocaine but only if I was on a cigarette boat in Miami with a bunch of hookers. Other than that I'm not trying it.
      • 2 Years Ago
      Research was funded by the tobacco industry.
      • 2 Years Ago
      If you actually read the study, you can quickly determine most of this is total crap. In other news, people who listen to the radio are more likely to get in an accident than those who don't... I have a study, it's called how many people in North America actually know how to drive versus those who don't? Now THAT'S a study worth reading...
        • 2 Years Ago
        It's called the "Immigrant Factor". Too many cultures here. People move and bring their terrible driving habits with them. The more I travel the globe the more I recognize where all this crappy driving originates from.
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