Recreational marijuana became legal in Illinois in 2020. Since the first dispensaries opened a few months before the pandemic hit, more and more people have become regular cannabis users. The plant has numerous beneficial effects, from reduced anxiety and pain management to relief from a significant number of physical and mental health conditions.
While many cannabis users are well aware of legal restrictions around drinking and driving, they may not be so familiar with Illinois laws surrounding driving under the influence of marijuana. Just what are the limits on driving while high?
Two categories of impaired driving
Illinois law makes it illegal to drive while impaired by alcohol or other substances, including THC, the psychoactive component of marijuana. But how can police prove that you were impaired? There are two ways:
- Circumstantial evidence: If your behavior indicated that you were not capable of driving safely, you could be arrested and charged with DUI. If you were swerving over the centerline or ran a red light, for example, that may be adequate evidence. Field sobriety tests such as “walking the line” may also demonstrate impairment, but those tests aren’t always accurate, and there may be ways to challenge them in court.
- Blood, saliva or urine tests: You can be charged with “driving over the limit” – that is, a “per se” violation of the law – if you had a blood test showing at least 5 ng/ml of THC in your bloodstream or at least 10 ng/ml in your saliva or urine, within two hours after driving.
As with alcohol-related DUIs, Illinois’s implied consent laws mean you could face criminal charges for refusing to comply with a blood, saliva or urine test, assuming the police had adequate grounds to pull you over.
Avoiding marijuana-related DUI charges
The unfortunate reality is that the chemical limit for THC is somewhat arbitrary. Theoretically, you could get charged with a DUI for THC levels above the limit even if you weren’t actually high while driving. Police can’t stop you without legal grounds, however, so the simplest way to avoid getting pulled over is to meticulously follow all traffic laws.
If you do find yourself facing charges for a marijuana-related DUI, it’s important to take the charges seriously. A conviction could have a big impact on your driving privileges, employment opportunities and future.