Lexis Nexis - Case Brief

Not a Lexis+ subscriber? Try it out for free.

Law School Case Brief

Mitchell v. Wisconsin - 139 S. Ct. 2525 (2019)


In a situation where there is no time for a police officer to secure a warrant before a blood test of a drunk-driving suspect, exigency exists when (1) blood alcohol concentration (BAC) evidence is dissipating and (2) some other factor creates pressing health, safety, or law enforcement needs that would take priority over a warrant application. Both conditions are met when a drunk-driving suspect is unconscious, so with such suspects, a warrantless blood draw is lawful.


Petitioner Gerald Mitchell was arrested for operating a vehicle while intoxicated after a preliminary breath test registered a blood alcohol concentration (BAC) that was triple Wisconsin’s legal limit for driving. As was standard practice, the arresting officer drove Mitchell to a police station for a more reliable breath test using evidence-grade equipment. By the time Mitchell reached the station, he was too lethargic for a breath test, so the officer drove him to a nearby hospital for a blood test. Mitchell was unconscious by the time he arrived at the hospital, but his blood was drawn anyway under a state law that presumes that a person incapable of withdrawing implied consent to BAC testing has not done so. The blood analysis showed Mitchell’s BAC to be above the legal limit, and he was charged with violating two drunk-driving laws. Mitchell moved to suppress the results of the blood test on the ground that it violated his Fourth Amendment right against “unreasonable searches” because it was conducted without a warrant. The trial court denied the motion, and Mitchell was convicted. On certification from the intermediate appellate court, the Wisconsin Supreme Court affirmed the lawfulness of Mitchell’s blood test. Petitioner Mitchell sought further review.


Does a state implied consent law authorizing a blood draw from an unconscious driver who could not take a breath test provide an exception to the Fourth Amendment search warrant requirement?




On certiorari, the Supreme Court of the United States considered what police officers may do in a narrow but important category of cases: those in which the driver is unconscious and therefore cannot be given a breath test. The Court held that in such cases, the exigent-circumstances rule almost always permits a blood test without a warrant. When a breath test is impossible, enforcement of the drunk-driving laws depends upon the administration of a blood test. When a driver is unconscious, there is a heightened urgency and a possible medical emergency; thus, the general rule is that a warrant is not needed.

The Court held that BAC tests are Fourth Amendment searches. The plurality determined that when the police had probable cause to believe a person had committed a drunk-driving offense and the driver’s unconsciousness or stupor required him to be taken to the hospital or similar facility before the police had a reasonable opportunity to administer a standard evidentiary breath test, they might almost always order a warrantless blood test to measure the driver’s BAC without offending the Fourth Amendment.

However, the Court vacated the judgment and ordered remand. Remand was necessary because the plurality did not rule out the possibility that in an unusual case a defendant would have been able to show that his blood would not have been drawn if police had not been seeking BAC information, and that police could not have reasonably judged that a warrant application would interfere with other pressing needs or duties, and petitioner Mitchell did not have a chance to attempt to make that showing.

Access the full text case Not a Lexis+ subscriber? Try it out for free.
Be Sure You're Prepared for Class