Drunk and drugged driving laws in Illinois

By the end of this topic you can

• You can state the legal alcohol and THC limits for Illinois drivers.
• You can explain the zero tolerance rule for drivers under 21.
• You can describe implied consent and what happens if you refuse testing.
• You can list the main license penalties for a DUI conviction.
• You can explain how cannabis must be carried in a vehicle.

What you need to know and understand

• It is illegal to drive with a blood-alcohol concentration (BAC) of .08% or more, and you can still be convicted below .08% if your driving is impaired.
• It is illegal to drive with THC of 5 nanograms or more per milliliter of whole blood, or 10 nanograms or more per milliliter of other bodily substance.
• Drivers under 21 with any trace of alcohol face a suspension of at least three months.
• A driver under 21 convicted of DUI faces revocation for at least two years on a first conviction.
• Failing a chemical test brings a six-month statutory summary suspension; refusing brings one year for a first offender.
• A first DUI conviction brings at least a one-year revocation.
• Cannabis may only be carried in a sealed, odor-proof, child-resistant container, and no one may use it in a vehicle.

Limits for alcohol, cannabis and other drugs

Your BAC depends on how much you drink, your tolerance, what you have eaten and any drugs you have taken. Only time removes alcohol; coffee, food and showers do not sober you up.

Cannabis is legal for adults 21 and older, medically or recreationally, but driving while impaired by it is not. Any trace of a controlled drug or intoxicating compound in your blood is also illegal. Many legal medicines, such as antihistamines, cold remedies and pain relievers, can impair driving too, and mixing them with alcohol is very dangerous.

Implied consent and testing

By driving in Illinois you automatically agree to breath, blood, urine or other tests if an officer suspects impairment. If a test shows .08% or more, or THC over the limit, your license is suspended for six months. Refusing the test means a one-year suspension. A second offender within five years faces one year for failing and three years for refusing.

The officer takes your license and gives you a receipt that lets you drive for 45 days; the suspension starts on the 46th day. If you refuse testing after a crash involving serious injury or death, your license is revoked for at least a year.

Penalties after a DUI conviction

Open alcohol containers are not allowed in the passenger area, and drivers under 21 who are caught with or drinking alcohol lose their driving privileges. A first offender may apply for a Monitoring Device Driving Permit, which requires a breath alcohol ignition interlock, but it cannot be issued to anyone under 18.

• First conviction: revocation of at least one year (at least two years if under 21).
• Second conviction within 20 years: at least five years.
• Third conviction: at least 10 years.
• Fourth or later: lifetime revocation.
• Before getting your license back: an alcohol and drug evaluation, treatment or education, a hearing with the Secretary of State, a reinstatement fee, and proof of insurance (SR-22) for three years.

Common mistakes

• Thinking one drink is safe for a driver under 21. Any trace of alcohol brings a suspension.
• Believing coffee or a cold shower will sober you up. Only time works.
• Carrying cannabis in an open bag or a pocket. It must be in a sealed, odor-proof, child-resistant container.
• Assuming refusing a test avoids a penalty. Refusal brings a longer suspension than failing.

Test yourself: Drunk and drugged driving laws in Illinois

Answer each question, then read the explanation. Questions come in a random order each time.

Go deeper

• Illinois Driver’s Ed Requirements for Under 18s
• Illinois GDL Rules
• Illinois Seat Belt, Child Restraint and Other Traffic Laws