The Cannabis Regulation and Tax Act was signed on June 25, 2019, and on January 1, 2020, adult consumers (persons 21 years or older) will be able to purchase marijuana in limited quantities from licensed sellers in Illinois. Though the legalization of marijuana is long overdue, there are some important things to keep in mind. First, the market will be regulated heavily. Second, it is still illegal to drive under the influence (DUI) of marijuana.

If you have been arrested for DUI marijuana, you will need the legal representation of an experienced DUI attorney. These cases are not only about the law, but they are highly technical and scientific. A thorough understanding of the tests and marijuana's impact on the body and driving capabilities is fundamental to a strong defense.

What is DUI Marijuana in Illinois?

DUI Marijuana in Illinois is driving under the influence of cannabis. The same rules that apply for driving under the influence of alcohol or any other drug also apply to driving under the influence of cannabis.

Under the current law, anyone who is not a medical marijuana license carrier can be arrested for being under the influence of Tetrahydrocannabinol (THC) – the chemical that produces the feeling of being high – and can be charged with DUI marijuana as well as possession of marijuana. If you are a medical marijuana license holder, then you are illegally intoxicated if 5 nanograms of THC or more per milliliter of blood is found in your system after a chemical test.

Once the new cannabis law takes effect on January 1, 2010, any adult found to have 5 nanograms of THC or more in his or her system will be presumed under the influence of cannabis. If concentrations are less than 5 nanograms, you will be presumed not under the influence of cannabis.

The Problem of Proving DUI Marijuana in Illinois

Proving intoxication by marijuana is difficult and will remain difficult after its legalization. The problem on the roadside, once pulled over, is this: there is currently no easy test to identify if you are intoxicated and/or impaired by cannabis. Given that marijuana will soon be recreationally legal to consume, Illinois is preparing for it.

The state has increased training of cadets on Advanced Roadside Impairment Driving Enforcement (ARIDE) and will increase the number of Drug Recognition Experts on patrol. These officers are trained – though controversially given the science behind the training is not completely proven and is tainted by other lawful factors – to identify when a person may be intoxicated by drugs.

The Presumption that DUI Marijuana Will Increase in Illinois

Ever since marijuana became recreationally legal in many states, there have been studies that suggest (but have not clearly proven) more people are driving under the influence of cannabis than ever before. This may or may not be true, but the presumption is that DUI marijuana increases after recreational legalization. What is true is this: there are more police officers trained to look for drivers who may be intoxicated by cannabis than there ever were before.

The problem with marijuana, however, is that traces of it remain in your system for days and weeks, well after the few hours you are influenced by the drug.

Factors that affect how long cannabis can be detected include:

• frequency of use;
• level of THC;
• your metabolism; and
• your hydration.

So, though the legalization of marijuana may increase the visibility of DUI arrests, keep in mind that these charges can be challenged successfully in court due in part to inherent technical difficulties. Always reach out to an experienced DUI marijuana attorney for advice and guidance if you have been arrested.