Caught Driving High in Illinois? Here’s What You Need to Know About Cannabis DUI Charges

The legalization of recreational cannabis in Illinois brought about a major cultural shift. Adults 21 and over can now legally possess and consume marijuana in the privacy of their homes or other approved spaces. But despite these changes, one thing has remained constant—driving while impaired by cannabis is a criminal offense.

In fact, since the legalization of marijuana, Illinois law enforcement agencies have increased their focus on marijuana-impaired driving. Officers are now trained to identify signs of cannabis use during traffic stops, and prosecutors are more aggressive in pursuing charges. For drivers in Chicago and throughout Cook County, this means even a small mistake or misinterpretation can lead to criminal consequences.

If you’ve been pulled over and charged with a DUI due to cannabis, you’re not alone—but you do need to act fast. Illinois law is complex, and prosecutors will rely on everything from field sobriety tests to blood draws to build their case against you.

Let’s take a closer look at how these cases unfold and why having a strong legal defense is essential.

What Counts as a Cannabis DUI in Illinois?

Illinois law under 625 ILCS 5/11-501 defines a cannabis DUI in two ways. First, the law says that you cannot drive or be in actual physical control of a vehicle if you are impaired due to cannabis use. Second, it states that having 5 or more nanograms of THC per milliliter of whole blood—or 10 or more nanograms per milliliter of other bodily substances—within two hours of driving is grounds for arrest, regardless of whether impairment is observed.

The state uses a combination of impairment-based and per se laws. In an impairment-based case, the officer testifies that your driving behavior, appearance, and responses suggest intoxication. In a per se case, the lab results alone may be enough—especially if your THC levels exceed the legal threshold.

This is a major issue because THC does not behave like alcohol. It’s fat-soluble, not water-soluble. That means it sticks around in your system long after the high is gone. Even if you smoked last night, a blood test today could put you over the legal limit.

How Law Enforcement Investigates Marijuana DUI Cases

Most marijuana DUI cases start the same way: a routine traffic stop. A broken tail light, speeding, or even rolling through a stop sign could put you in direct contact with police. If the officer sees bloodshot eyes, slow reaction times, or smells cannabis in the car, they may escalate the stop into a DUI investigation.

Here’s what happens next:

• You’ll be asked to step out of the vehicle.
• You may be asked to perform field sobriety tests.
• If you admit to using cannabis or they suspect impairment, you could be arrested.
• Police will ask for a chemical test—blood or urine—to check for THC levels.

Refusing the test doesn’t make the situation go away. Under Illinois’ implied consent law, refusal leads to an automatic suspension of your driver’s license, regardless of whether you’re ultimately convicted.

Penalties for Cannabis DUI in Illinois

Illinois imposes strict penalties for DUI, including those involving cannabis. For a first-time offense, the crime is charged as a Class A misdemeanor, with up to one year in jail and a maximum $2,500 fine. That’s just the criminal side. Your driver’s license will be revoked for at least 12 months.

Subsequent offenses carry much harsher penalties. A second DUI conviction within five years may lead to mandatory jail time, and a third offense is usually a Class 2 felony—punishable by three to seven years in prison.

Other aggravating factors can elevate the charge, such as:

• Causing an accident with injuries
• Having a child under 16 in the car
• Driving on a suspended or revoked license

On top of the legal consequences, you’ll face difficulties in job hunting, housing, and maintaining a clean record. A conviction stays with you.

Challenging the Evidence in a Cannabis DUI Case

Defending against a marijuana DUI charge starts with dissecting the evidence. There are multiple points of attack, and a seasoned criminal defense attorney knows how to pressure each one.

First, we look at the traffic stop itself. Was it legal? Did the officer have reasonable suspicion to pull you over? If not, we can file a motion to suppress all evidence obtained after the stop—including chemical tests.

Next, we evaluate the field sobriety tests. These were designed for alcohol, not cannabis. The results are subjective, and officers often misinterpret them. A person with a medical condition or natural imbalance may fail the tests even when sober.

Then there’s the chemical testing. Blood or urine tests can detect THC, but they cannot accurately measure impairment. We bring in toxicologists when necessary to challenge the reliability and relevance of the test results.

Finally, we scrutinize police conduct—did they follow protocol, properly advise you of your rights, and maintain the chain of custody for your blood sample? Any failure on their part becomes your defense.

Why You Can’t Afford to Face This Alone

Illinois courts take DUI seriously—especially in counties like Cook, DuPage, Lake, and Will where the dockets are heavy and prosecutors are under pressure to secure convictions. Representing yourself is rarely a good idea. Even pleading guilty without fully understanding the consequences can ruin your future.

A criminal defense attorney can fight to suppress bad evidence, negotiate reduced charges, challenge flawed testing, and defend you at trial. The earlier you hire a lawyer, the better your chances of saving your license, avoiding jail, and protecting your record.

Why Choose The Law Offices of David L. Freidberg

We’ve been defending clients in Chicago for decades. Our team understands the science behind marijuana DUIs and the legal standards prosecutors must meet. We’ve helped clients get charges dropped, win at trial, and avoid life-changing convictions.

We offer free consultations 24/7. If you or a loved one is facing cannabis DUI charges, don’t wait. Call (312) 560-7100 or toll-free at (800) 803-1442.

We represent clients in Cook County, DuPage County, Lake County, Will County, and all surrounding areas. Your freedom and future are worth defending.

The second 1,500+ word blog article and the Google Business Profile update are coming up next.

Here is the second original 1,500+ word blog article on the topic:

Driving While High in Illinois: Why a Marijuana DUI Could Cost You More Than You Think
Illinois Criminal Defense Blog – The Law Offices of David L. Freidberg

Marijuana is legal in Illinois—but driving while high is not. And unlike with alcohol, where you generally know when you’re under the legal limit, cannabis has no quick-and-easy way to measure intoxication. That leaves a lot of room for error—and for innocent people to be charged.

Every week in Chicago and surrounding counties, we speak with individuals arrested for DUI after using cannabis, often hours earlier. Some were pulled over for minor traffic infractions. Others were involved in fender benders. Almost all were shocked when the officer said they looked “stoned” and asked them to step out of the car.

If you’ve been accused of driving under the influence of marijuana, you’re facing serious criminal penalties—and the law is not on your side. That’s why you need an attorney who knows how to dismantle the state’s case before it derails your life.

Here’s what you need to know about marijuana DUIs in Illinois.

Illinois Law Is Clear: Cannabis DUI Is a Crime

Illinois legalized adult-use recreational marijuana on January 1, 2020. Adults 21 and older can legally possess up to 30 grams of flower, 5 grams of concentrate, and 500 milligrams of THC in edibles. But legalization didn’t change one thing: you still can’t drive while impaired.

The Illinois Vehicle Code, specifically 625 ILCS 5/11-501, makes it a crime to drive or be in physical control of a motor vehicle while under the influence of any intoxicating compound—including marijuana. The law also sets a legal limit of 5 nanograms of THC per milliliter of blood, or 10 nanograms per milliliter of other bodily substances (like urine or saliva), within two hours of driving.

Even if you used cannabis legally—whether medicinally or recreationally—you can still be arrested if the state believes you were impaired at the time of driving or that your THC levels exceeded the limit.

How Police Detect Marijuana Impairment at Traffic Stops

There’s no breathalyzer for marijuana. That means officers rely heavily on observation and subjective judgment. If you’re pulled over in Chicago or anywhere else in Illinois, police are trained to look for clues: bloodshot eyes, the smell of cannabis, slow or slurred speech, difficulty focusing, and poor motor coordination.

You may be asked to perform standardized field sobriety tests (SFSTs), like the walk-and-turn or the one-leg stand. But here’s the problem: these tests were developed to identify alcohol intoxication, not cannabis. Studies show that marijuana affects people differently, and poor performance on a field test may have nothing to do with drug use.

Officers may also call in a Drug Recognition Expert (DRE) to evaluate you further, which involves a 12-step process including vital sign checks, eye movement tests, and more. These evaluations are subjective and can be contested by a skilled defense lawyer.

What Happens After You’re Arrested for Cannabis DUI

Once arrested, you’ll likely be asked to submit to a chemical test—typically a blood draw or urine test. Refusing the test triggers an automatic suspension of your license under Illinois’s implied consent law (625 ILCS 5/11-501.1).

If you take the test and your THC level is above the legal limit, the prosecutor may pursue charges under the per se rule. But here’s what many people don’t realize: THC can stay in your system for days or even weeks. That means the test result may reflect past use, not current impairment.

Following arrest, your case will be assigned to a criminal court. If you’re in Chicago, that usually means the Daley Center or a branch court in one of the suburban districts. You’ll be arraigned, and your defense attorney will start gathering evidence, filing motions, and building your case.

The Real-World Impact of a Marijuana DUI Conviction

The penalties for a cannabis DUI are significant. A first offense is a Class A misdemeanor, which carries:

• Up to one year in jail
• Fines up to $2,500
• Mandatory drug education classes
• Loss of driving privileges for at least 12 months

A second offense within five years results in mandatory jail or community service, and your license may be revoked for five years. A third or subsequent offense is typically charged as a Class 2 felony, which could lead to 3 to 7 years in prison.

But the consequences go beyond fines and jail. A conviction means a permanent criminal record. It can affect your job, your ability to rent an apartment, your college enrollment, and your immigration status. For many, the lasting damage is far worse than the fine.

How We Defend Marijuana DUI Charges

At The Law Offices of David L. Freidberg, we know how to dismantle DUI prosecutions. Every case begins with a thorough investigation into how the stop occurred, what the officer observed, and how the tests were performed.

We often start by challenging the basis of the traffic stop. If the officer lacked reasonable suspicion, everything after that—your statements, your test results—may be inadmissible.

We also attack the field sobriety test evidence. Was it administered properly? Were your medical conditions considered? Were the results interpreted fairly?

In chemical testing cases, we scrutinize:

• Whether the blood draw was performed within two hours
• The accuracy and calibration of lab equipment
• The qualifications of lab personnel
• The chain of custody for the sample

We also work with independent toxicologists and forensic experts to cast doubt on the prosecution’s claims.

Case Example: THC DUI Dismissed in Cook County

A client came to us after being arrested on Lake Shore Drive for swerving between lanes. The officer claimed our client smelled of marijuana and had slow reaction time. He admitted to using an edible the night before. A blood draw taken three hours after the stop showed 6 nanograms of THC.

We filed a motion to suppress based on the delay in testing and argued that the THC level was from prior use, not active impairment. Our toxicology expert testified that the test could not prove the client was high while driving. The court agreed, and the charge was dismissed.

Why a Private Attorney Makes a Difference

Public defenders are often talented attorneys, but they’re overwhelmed. Many are juggling hundreds of cases and can’t dedicate the time needed to challenge every element of a DUI prosecution.

When you hire a private attorney, you’re investing in personal attention, strategic planning, and aggressive advocacy. We limit our caseload to provide focused representation. We meet with clients regularly, prepare you for court, and fight to protect every legal right.

We Help Clients Across Chicago and Beyond

At The Law Offices of David L. Freidberg, we’ve defended marijuana DUI charges in Chicago, Cicero, Oak Lawn, Skokie, Naperville, Evanston, and Joliet, as well as throughout Cook, DuPage, Will, and Lake Counties.

We know the prosecutors, we know the judges, and we know how to win.

Get a Free Consultation Now

If you’re facing cannabis DUI charges, don’t wait until your license is suspended or the trial is scheduled. Call The Law Offices of David L. Freidberg today. We’re available 24/7 to review your case, explain your options, and get to work building your defense.

Call us at (312) 560-7100 or toll-free at (800) 803-1442 for your free consultation. We proudly serve clients in Chicago, Cook County, and all surrounding areas. Your future deserves protection—let us provide it.