Driving after using marijuana could cost you more than you think.
How long after smoking marijuana can you get a DUI in Michigan?
You can be charged with a marijuana DUI in Michigan if an officer believes you’re impaired while driving—regardless of how long ago you used cannabis. There’s no legal THC limit.
With decades of experience in Michigan’s DUI laws, I can guide you through the nuances of these regulations.
In this article, we’ll delve into the specifics of Michigan’s marijuana-related driving laws, how impairment is determined, and what steps you can take to stay compliant and safe on the road.
Michigan’s Marijuana DUI Laws Explained
Under Michigan Compiled Laws § 257.625, it is illegal to operate a motor vehicle while:
- Under the influence of alcohol, marijuana, or any controlled substance
- Visibly impaired by any intoxicant, regardless of legality
- Having any amount of Schedule 1 controlled substances in your system (note: marijuana was removed from this category after legalization)
Important distinction:
Michigan does not use a THC blood concentration limit like it does for alcohol (0.08 BAC). That means you can be charged even if THC is present at very low levels—as long as the officer claims you were impaired.
How Long Does Marijuana Stay in Your System?
| User Type | Detection Window (Blood Test) |
|---|---|
| Occasional User | 6–24 hours |
| Regular User | 2–7 days |
| Heavy Daily User | 7–30+ days |
THC can remain in the bloodstream well after its impairing effects wear off. The timeline depends on the amount used, frequency of use, body fat percentage, and individual metabolism. Additionally, marijuana can stay in a person’s system for at least 30 days due to THC being stored in fat cells. The effects of THC are most powerful in the first 30 minutes after use, which is when the risk of impairment is highest.
Driving immediately after using marijuana increases the risk of crashing by 25 to 35%. While THC can remain in a person’s system for up to 30 days, the intoxicating effects typically last only a few hours.
But detectable does not mean impaired. That’s why blood THC levels alone are not a reliable measure of DUI in Michigan. The presence of Carboxy-THC, an inactive metabolite, does not cause impairment and should not be used as sole evidence of intoxication. THC, however, can impair cognitive and motor skills, including judgment and reaction time, which are critical for safe driving.
What Police Look for in a Cannabis DUI Stop
If pulled over on suspicion of marijuana use, officers may rely on:
- Erratic driving or traffic violations
- Red eyes, slurred speech, or the smell of marijuana
- Open containers, paraphernalia, or admission of recent use
- Field Sobriety Tests (FSTs)
- Drug Recognition Evaluator (DRE) assessment
A DRE is a specially trained officer who evaluates your coordination, pupil size, blood pressure, pulse rate, and other physical indicators. Field sobriety tests, which aim to measure coordination and balance affected by marijuana, are often used in conjunction with these evaluations.
Blood or urine tests may follow—but these only prove use, not impairment. Blood tests, however, are considered one of the most reliable methods for detecting recent cannabis use. Blood and urine tests are commonly used to detect THC in the body, but their results do not necessarily correlate with current impairment levels. Saliva swab tests are gaining popularity for roadside testing of THC presence and provide almost immediate results.
Can You Be Charged Even If You’re Not High?
Yes. You can be arrested and charged with DUI based on an officer’s opinion of your behavior, regardless of how long it’s been since you smoked. Refusing a blood test after being pulled over for suspected DUI can lead to an immediate license suspension for one year. Additionally, you only have 10 days to save your license after a DUI arrest, making it critical to act quickly and consult with a defense attorney.
For example:
- If you used cannabis the night before and still have THC in your blood
- If you smoked several hours ago but drove poorly due to fatigue or distraction
- If you failed field sobriety tests, even with no recent use
In these situations, an aggressive criminal defense strategy is essential to challenge subjective police observations and weak forensic evidence. Failure to prove actual impairment can lead to overturning a DUI conviction based on THC metabolites. Judges can also exclude evidence that a driver smoked marijuana weeks prior as irrelevant for impairment.
Defending Against Marijuana DUI Charges in Michigan
At D.G. Moore, we use proven legal defenses to challenge cannabis DUI allegations, including:
- Lack of evidence of impairment
- Inaccurate or improperly conducted FSTs
- Unreliable DRE assessments
- Invalid blood or urine testing procedures
- Lack of probable cause for the traffic stop
We also consult with toxicologists and medical experts when necessary to dispute claims that THC presence equals impairment.
What to Do If You’re Pulled Over After Smoking
If you’re stopped by police after using marijuana:
- Stay calm and respectful
- Provide license, registration, and proof of insurance
- Do not admit to recent marijuana use
- Politely decline to perform FSTs or answer questions about drugs
- Do not consent to a search unless required by law
- Request to speak with a criminal defense attorney immediately
Remember, you have the right to remain silent and the right to legal counsel.
Accused of a Marijuana DUI in West Michigan? Contact D.G. Moore Now.
If you’ve been arrested for marijuana-related DUI in Michigan, you need an experienced criminal defense attorney on your side immediately. At D.G. Moore, we’ve successfully defended clients against DUI charges in Grand Rapids and beyond using aggressive, evidence-based strategies.
Call 269-808-8007 for a free case evaluation
Or schedule a confidential consultation online
Don’t let a THC arrest ruin your future—we’ll fight to protect your freedom and your record.