Are you reading this because you or someone you love was just arrested for an OWI after taking a prescribed medication, or after using marijuana that was perfectly legal where you bought it? Many people assume that because a doctor prescribed the medication, or because the marijuana was purchased legally in a neighboring state, they’re protected. Unfortunately, that isn’t always how Wisconsin law works.
Wisconsin’s drugged driving laws catch people off guard. The state does not always need to prove you felt impaired behind the wheel to secure a conviction. At the criminal defense law firm of Casper Mehlos Law Group, our drug crime defense attorneys can help.
The Substance Determines the Legal Path
Wisconsin handles OWI cases in two different ways, and which path applies to you depends on the substance involved. For many prescription medications, the state generally must show that you were impaired, meaning your ability to drive safely was affected at the time. For a smaller category of substances, including THC, the law is much stricter. In those cases, simply having a qualifying amount in your blood can be enough to support a charge, regardless of how you were driving. Wisconsin’s law on operating with a restricted controlled substance is found in Wis. Stat. § 346.63.
Can You Be Charged With an OWI for THC If You Weren’t Impaired?
Yes. Wisconsin doesn’t measure THC the way it measures alcohol. There’s no 0.08 style cutoff. Even a small, trace amount, often as little as 1 nanogram per milliliter, can support a charge, and because THC can stay in the bloodstream long after any effects have faded, someone can be arrested days after using it. You can read more in our guide on how prescription medications or marijuana can lead to an OWI charge.
Is a Valid Prescription a Defense to a THC-Related OWI?
There is a narrow legal defense available for people who hold a valid prescription for certain THC-based medications. This defense has to be supported with real documentation, though, so no one can assume it will simply be accepted by the court.
Prescription Medications and OWIs
Medications like pain relievers, anxiety medications, or sleep aids are generally evaluated under the impairment-based standard. The state typically has to show your driving was affected, not just that the medication was present. Even so, having a valid prescription isn’t a guaranteed shield from a conviction. If your dosage exceeded what’s considered a normal therapeutic level, or if an officer documented signs they believed showed impairment, you may still be facing real consequences.
How Do Officers Show Impairment Without a Blood Alcohol Number?
Officers typically rely on their observations of your driving, your behavior, and field sobriety tests. Those observations can be challenged, and we explain how in our article on fighting a failed field sobriety test in Wisconsin. For a broader look at how these cases are defended, see building a strong defense against drugged driving charges.
We See This Often Around Madison, and We Understand the Roads You Drive
Many of our clients are stopped along familiar stretches, the Beltline, John Nolen Drive, University Avenue, or out along I-90 heading toward Wisconsin Dells. Sometimes it starts with something small, a broken taillight or a rolling stop, and turns into a much bigger conversation once a law enforcement officer starts asking questions. Lawyers at Casper Mehlos Law Group represent clients throughout Dane, Rock, Columbia, Sauk, Iowa, and Green Counties, and we’ve come to recognize how quickly a routine stop can spiral into something that feels frightening and unfair.
What Should You Do After a Drugged Driving Arrest in Wisconsin?
Speak with an attorney early, and gather your prescription records and any documentation of your medication and dosage. To understand what may be at stake, review what happens after a first OWI in Wisconsin and the Dane County first-offense OWI penalties. If your license is at risk, see how to get an occupational license in Dane County after an OWI.
Don’t wait until you have all the paperwork, or until the lab results come back, to contact a skilled defense attorney. Let us help you understand your options and protect your rights.
