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Drivers High on Marijuana Twice as Likely to Crash

Written by Jared Staver

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Jared Staver is a Personal Injury Lawyer based in Chicago, Illinois and has been practicing law for over 25 years.

Jared Staver

CATEGORY: Auto Accidents, Personal Injury


According to a study published in the Society for the Study of Addiction’s journal, there is ample evidence that drivers who are high on marijuana are twice as likely to get into a car crash than sober drivers. This research yet again demonstrates the dangers of driving while under the influence of marijuana. It also reinforces the importance of having laws prohibiting driving while high on marijuana. DUIs for driving under the influence of marijuana should stay illegal.

Still, it is sometimes difficult to know exactly how to measure the level of marijuana in a person’s system and determine if a person has violated DUID laws. In Illinois, this line is murky. While technically Illinois has per se law and a zero tolerance policy for any trace amount of marijuana in a person’s system, efforts to reform this policy have been made in the last few years. Last year, the Medical Cannabis Act was passed to exclude people with a legal, registered medical marijuana card from being subject to these same standards. There has been talk of extending this to others, so long as they are not currently high.

This legal change may be a good policy in Illinois, as a way to make the punishment for drugged driving fair for the crime. Some may say that it is not fair to prosecute legal users of marijuana for trace amounts of the drug in their bodies, if they are no longer high. This may be important, since marijuana can be detected weeks after it was last consumed, even though it does not affect your likelihood of a crash anymore.

The Dangerous Effects of Marijuana

Marijuana impacts users differently depending on their weight, metabolism, and more. The drug may affect a woman who weighs approximately 125 pounds much differently than a man who weighs 180 pounds. Additionally, various marijuana products have different potencies. Each of these individuals will be more significantly affected by a marijuana product containing 100 milligrams of THC compared to if they smoked or ingested approximately 10 milligrams of the compound. There can also be meaningful differences between smoking marijuana and absorbing THC through the lungs as compared to ingesting an edible form of the drug and absorbing THC through the digestive tract. Smoking marijuana produces an instant high that quickly diminishes. Ingesting the drug leads to a delayed effect. It can take up to an hour to become high, which can then last for a significantly longer period of time.

While the specific impact of marijuana on individuals varies based on a number of factors, there are common side effects of using this drug, including:

  • Slowed reaction time
  • Impaired perception of time
  • Impaired perception of distance
  • Diminished coordination
  • Drowsiness

It is obvious how all of these side effects can affect a person’s ability to safely drive. Drivers need to be able to accurately detect distance and speed as well as quickly react to hazards in the road. High individuals are unable to perform these tasks well.

Illinois’ Law Against Drugged Driving

In 2016, Illinois’ zero-tolerance policy against operating a vehicle with any marijuana in the driver’s system changed. Now, Illinois has a more objective standard for what is considered drugged driving. It is unlawful for individuals to drive with 5 nanograms or more of THC in their blood or 10 nanograms or more of THC in their saliva. This standard enables the police and courts to treat marijuana more like alcohol in relation to driving. If the police suspect an individual is driving while high, they can arrest the driver and conduct an official blood or saliva test.

Putting Marijuana Crash Statistics in Perspective

It is also important to put the crash statistic in perspective. While anything that doubles the risk for an accident is dangerous and worth preventing while driving, it is important to prosecute all risks evenly. Texting and driving similarly doubles a person’s risk of a crash, but it only carries a minor fine here in Illinois, instead of up to a year in prison and a loss of your license for the first offense.

Even a DUI for alcohol that carries the same punishment as one for marijuana is not quite on the same level. According to Mothers Against Drunk Driving, a BAC of just above the legal limit makes a person 11 times more likely to be involved in a fatal crash than a sober driver. This statistic indicates that driving under the influence of alcohol may be a much more serious risk. As you can see, all of these actions should be equally avoided in order to avoid a car accident.

Our car accident attorneys serve clients throughout the Chicago area, including Aurora, Elgin, Hinsdale, Joliet, Naperville, and Waukegan. If you have been smoking marijuana within the last several hours, you should not be driving. Don’t risk a dangerous accident that could be your fault. If you are injured in an accident as a result of someone smoking marijuana, you may need the help of an experienced Chicago accident attorney to help you deal with the insurance company. Call us today at Staver Accident Injury Lawyers, P.C. at (312) 236-2900 to see how we may be able to help.

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(312) 236-2900
(312) 236-2900
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