Can You Get a DWI Dismissed in Minnesota Because of an Illegal Traffic Stop? 
Short answer: yes. Longer answer: Potentially (one of a lawyer’s favorite non-committal words). First, the accused needs to establish an unlawful basis for the traffic stop (seizure) under Fourth Amendment constitutional protections. Then, the district court needs to grant the defense’s motion to suppress the prosecution’s evidence obtained after an unlawful seizure. Motions to suppress are routinely combined with motions to dismiss in DWI cases. Suppressing the evidence of a breath, blood, or urine test result for a charge such as DWI .08 or More Within Two Hours of Driving, Operating, or Being in Physical Control of a Motor Vehicle can leave the prosecution with insufficient evidence to prove that particular charge. When that happens, dismissal is often the result.
When Can Police Legally Pull You Over in Minnesota?
Officers do not need to suspect a DWI to legally pull you over in Minnesota. What they generally need is reasonable, articulable suspicion that a traffic violation or criminal activity occurred. This is a lower standard than probable cause. The typical driving conduct people think about with DWIs is someone swerving all over the road. They could be streaming videos on their phone, placing bets on prediction markets, or taking a selfie. But, they also could be under the influence of alcohol or drugs. Challenging the basis for the traffic stop in those cases is often and uphill battle. But, officers also stop people for minor traffic infractions, such as speeding, failing to signal a lane change or turn, driving over the fog line. And for equipment violations, such as no headlights on, broken taillights, etc. Reviewing the video of the traffic stop and comparing it to the applicable statutes and case law in Minnesota can lead to a basis to challenge the traffic stop in court depending on the circumstances.
Can a Legal Traffic Stop Turn Into an Illegal DWI Investigation?
Whether you were driving 100 mph like an F1 driver, swerving on the road while filming your podcast, or merely had a license plate light out, traffic stops can easily turn into DWI investigations, especially when the officer smells the seven Busch Lights you drank earlier on your breath. Sometimes, the officer does not smell beer or other alcoholic beverages on your breath. But, the cop wants to pull you out of your car and have you do field sobriety testing to investigate you for DWI. Can they do that? In Minnesota, each incremental police intrusion during a traffic stop must be individually justified. In State v. Askerooth, the officer pulled someone over for running a stop sign. The driver could not produce a driver’s license or any identification. The officer pulled the driver out of the car, patted him down for weapons, and placed him in the back of the squad car. While in the squad car, and after obtaining consent to search the vehicle, the officers found no drugs in the vehicle. But after releasing the driver from the back of the squad, the cops found illegal drugs he discarded. The Minnesota Supreme Court determined the additional intrusion was unconstitutional because it was not reasonably related to the original purpose of the stop, and it lacked independent probable cause, and the police lacked reasonable, articulable suspicion of different criminal activity.
What Happens When Police Illegally Expand a Traffic Stop?
Just because the initial traffic stop was legal does not mean everything the officer did afterward was constitutional. The defense lawyer should examine when the traffic stop turned into a DWI investigation and what fact the officer had at that particular moment. Did the cop smell Busch Light? Did the driver admit to taking twelve shots of tequila? Were there bloodshot eyes, slurred speech, or other indications of impairment? Or, did the officer simply decide to go fishing for a DWI because it was 2 a.m.? Reviewing the squad video, body camera footage, police reports, and officer testimony (if occurred yet) can reveal whether the officer had a lawful basis to expand the stop. If an officer illegally expands a traffic stop, then the defense attorney should file a motion to suppress any evidence obtained by the illegal expansion and include a motion to dismiss if the fruits of the search are vital to the offense(s) charged.
Does an Illegal Traffic Stop Automatically Dismiss a DWI?
Suppression does not automatically dismiss a DWI. For DWI charges that rely on a test result, then those DWI charges are almost assuredly being dismissed. For DWI charges, such as Under the Influence of Alcohol, Under the Influence of a Controlled Substance, or Under the Influence of Cannabis, it depends on what evidence the prosecutor has remaining after the suppression. If the driving conduct is minor, the field sobriety testing looks decent, and the person does not appear under the influence, then the better chance you have of the prosecutor dismissing the under the influence charge, getting a better plea deal, or winning at trial.
Whether an illegal traffic stop results in a dismissed DWI charge is fact dependent. Sometimes, the issue is whether the officer had a legitimate reason to pull you over in the first place. Other times, the problem is what the cop did after pulling you over. Either way, challenging the constitutionality of the stop can be one of the most effective defenses to a DWI charge in Minnesota.
Robert H. Ambrose is a criminal defense and DWI lawyer representing clients in Minnesota and Wisconsin, with offices in Woodbury and Minneapolis. He is also licensed to practice in federal court, has been recognized by Super Lawyers for the past five years, serves as an adjunct professor at the University of Minnesota Law School.