Driving while stoned can lead to criminal charges for driving while intoxicated (“DWI”). Driving while stoned and driving while drunk crimes are similar in many ways, including the possible penalties and license revocations . Additionally, like with alcohol where you can have one beer and drive, it is not criminal to merely have some marijuana in your system.

However, the differences between driving drunk and driving stoned crimes are very important. Unlike with alcohol, there is no established or accepted legal limit for marijuana. Also, there is no roadside breathalyzer equivalent to test for marijuana impairment.

Because of these unique challenges, the State cannot revoke your driving privileges until after you have been convicted. Even with these differences, the State can still convict you for driving while stoned if they can still prove you were “impaired”.

The Prosecution Can Prove Impairment Through Circumstantial Evidence.

In most marijuana DWI cases, the State will use any of the following evidence.

1. Driving conduct. If a police officer or witness observes you swerving, not using your signal, or otherwise driving poorly, the State will say the marijuana caused this.
2. Physical signs. Police are trained to check for any physical signs of impairment, including red/bloodshot eyes, slowed movements, droopy eyes, and speech patterns.
3. Admissions. Especially now that marijuana is legal, many people will admit they smoked before driving. A passenger or other witness may say something too.
4. Field sobriety testing. While the standard tests are not validated to detect marijuana impairment, law enforcement officers are still trained to administer the familiar eye tracking, walk and turn, and balancing tests used for alcohol.
5. DRE evaluation. Most departments have officers trained to be “drug recognition experts” and who go through far more advanced training. Best police practices are to bring a suspected stoned driver before a DRE as soon as possible.
6. Physical Evidence. Any marijuana found in the car, the smell of marijuana, and paraphernalia can be used as evidence to suggest you smoked recently.
7. Toxicology results. Because there is no marijuana breathalyzer, police will need to obtain a warrant to test your blood or urine. These results will then be used to suggest you were stoned while driving.

What Your Defense Attorney Can Do.

A skilled defense attorney can dramatically increase your chances of beating a marijuana DWI charge. In some cases, your attorney can challenge the reason for the traffic stop. More often, your attorney can challenge the evidence of impairment. As outlined above, the State’s evidence in marijuana DWI cases is circumstantial. There is no scientific test saying X level in your system = criminally impaired.

Thus, your attorney can challenge the law enforcement officer’s ability to detect impairment by reviewing their training and the body camera video. The State will also need to bring in the lab analyst to testify about any blood or urine test results. Your attorney can question the analyst about these results and point out studies showing that current scientific research has been unable to establish any reliable relationship between THC levels and impairment.

If you or someone you know has been accused of driving while stoned in Minnesota, don’t wait to get the legal help you need. Contact McKinney Defense today by calling (612) 300-1208 or filling out our online form to schedule a FREE consultation. Let me fight for your rights and help you take the first step toward fair representation.

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This blog post (“post”) is provided for general informational purposes only and may not reflect the current law in Minnesota or your jurisdiction. No information in this post should be construed as legal advice from the individual author or the law firm, nor is it intended to be a substitute for legal counsel on any subject matter. No reader of this post should act or refrain from acting based on any information included in or accessible through this post without seeking the appropriate legal or other professional advice on the particular facts and circumstances at issue from a lawyer licensed in the recipient’s state, country, or other appropriate licensing jurisdiction.