MINNEAPOLIS (WCCO) — The Minnesota Court of Appeals issued a decision Tuesday declaring that law enforcement must have a warrant before giving a blood test to a suspected impaired driver.

The opinion, written by Judge Jill Flaskamp Halbrooks, states that the 2012 subdivision of Minnesota’s Driving While Impaired laws that makes it a crime for refusal to submit to a chemical test — blood, breath or urine — is unconstitutional.

The decision was made in connection to the first-degree test refusal conviction of Todd Trahan, who was pulled over by a Ramsey County deputy in the fall of 2012 for speeding and erratic driving.

The deputy said Trahan — who had previous DWI convictions and was driving with a cancelled license — was agitated and unpredictable during their encounter. He also smelled of alcohol, had red, watery eyes and struggled to stand up. The deputy decided to skip giving Trahan field sobriety tests and took him straight to jail.

Trahan was given the option of taking a blood or urine test while in jail, choosing urine. After the urine test, Trahan says the deputy accused him of tampering with the test. He was then asked to submit to a blood test, which he refused.

The state charged Trahan with the refusal, for which he pleaded guilty, and he was eventually sentenced to 60 months in prison.

Trahan appealed the conviction, arguing both that his guilty plea was invalid because he had complied with the urine test, and that the test refusal law is unconstitutional because it violates due process.

His appeal was denied in September of 2014 because a district court believed his refusal supported his plea, and that he did not “meet his burden of establishing the unconstitutionality of the test-refusal statute beyond a reasonable doubt.”

The Minnesota Court of Appeals reinstated Trahan’s appeal about three months later, but the Minnesota Supreme Court remanded him in April of 2015 in light of the State vs. Bernard decision made by the appeals court one month earlier.

In that case, the court decided that the Fourth Amendment does not prevent the state from charging a suspected drunk driver’s breath test refusal “when the circumstances established a basis for the officer to have alternatively pursued a constitutionally reasonable non-consensual test by securing and executing a warrant.”

The Bernard decision caused Trahan and his lawyers to focus his argument on how the search of his blood was unconstitutional and violated his right to substantive due process — specifically how the search-incident-to-arrest exception used in the case concluded that only warrantless breath tests are constitutional.

The court disagreed that the dissipation of alcohol in the blood stream gave necessity to a warrantless blood draw. But they did agree in Trahan’s case that blood draws are intrusive because the body is pierced by a needle in order to retrieve the sample, and therefore could be considered an unreasonable search.

Halbrooks wrote that although a warrantless blood test “relates to the state’s ability to prosecute drunk drivers and keep Minnesota roads safe,” it does not pass the strict-scrutiny review, which is used to determine the government’s interest versus a constitutional right.

The Ramsey County Attorney’s Office plans to appeal the decision.

Judge Margaret Chutich decided in agreement with Halbrooks, while Judge Kevin Ross dissented. Ross, the author of the State vs. Bernard opinion, says this decision could lead to requiring law enforcement to obtain warrants in all cases involving suspected drunk drivers.