When it comes to DUI, there is a critical difference between alcohol and illegal drugs such as marijuana. You probably know that drunk driving is only a criminal offense if your blood alcohol concentration is 0.08 percent or higher. This means that most people can have one or two beers in their system and not worry about legal liability.
However, when it comes to illegal drugs, Illinois law states that “any amount” in a person's system is unacceptable. In other words, if police find any amount of THC—the active ingredient in marijuana and cannabis products—in your system, you are guilty of DUI even if there is no evidence that you were impaired. Additionally, if you are arrested for a DUI where someone else is seriously injured, you can be charged with an “aggravated” DUI which carries stiffer criminal penalties.
Illinois Supreme Court Rejects “Medical Condition” Defense in Aggravated DUI Case
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