Court: Defendant was not entitled to challenge DWI urine test reliability

The Minnesota Supreme Court ruled Wednesday that a defendant who has been charged with driving while impaired based upon a “first-void” urine test is not entitled to a hearing to challenge the reliability of that urine test because blood alcohol concentration is not relevant in a DWI case involving a urine test.

The defendant requested a hearing to challenge the scientific reliability of first-void urine testing in his DWI case. The trial court denied the hearing and the defendant was later convicted of a Minnesota DWI charge.

The Court ruled that the defendant was not entitled to the hearing and upheld the conviction. The defendant had asked the trial court to allow him the opportunity to show that first-void urine testing is unreliable to show impairment, because alcohol pools in the bladder and a urine test may show results that do not correlate to blood alcohol content.

The Supreme Court ruled that blood alcohol concentration is irrelevant if law enforcement chooses to test a DWI suspect through a urine test. The high court says that Minnesota statutes provide law enforcement with three methods of alcohol testing in DWI cases, including breath, blood or urine testing. Each method has its own specified “alcohol concentration” level of 0.08 percent.

The court says, “The presence or absence of a correlation between urine alcohol concentration using the first-void method and blood alcohol concentration does not make the existence of a 0.08 or higher alcohol concentration in [the defendant’s] urine any more or less probable.”

The ruling says that the trial court was not required to hold a hearing to allow the defendant to present evidence to support the challenge, because, “a lack of correlation to blood alcohol concentration was not relevant to the alcohol-concentration offense.” The court says that requiring a correlation to blood alcohol levels in a urine test DWI case would add an element to the offense that the legislature did not include in the law.

The court reasoned that the state would have to show a correlation to impairment from blood alcohol concentration in urine test cases, something the court determined the legislature does not require to show impairment.

Source: Minnesota Supreme Court, “State v. Tanksley, A10-0392,” Feb. 8, 2012

Max Keller has won countless jury trial cases involving misdemeanors and felonies, sex crimes, and DWI’s. He is a member of the Minnesota Society for Criminal Justice, which only allows the top 50 criminal defense attorneys in the state as members. Max is a frequent speaker at CLE’s and is often asked for advice by other defense attorneys across Minnesota.

Experience: Practicing since 1997
Minnesota Registration Status: Active
Bar & Court Admissions: State of Minnesota Minnesota State Court Minnesota Federal Court 8th Circuit Federal Court of Appeals State of Maryland

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