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Wisconsin, in fact, did not make any such argument while defending the blood draw and even conceded that the situation was not so pressing that its officers couldn't take the time to get a warrant. Writing in dissent, Justice Sonia Sotomayor, joined by Justices Ruth Bader Ginsburg and Elena Kagan, questioned whether the exigent circumstances described by the Court's judgment actually existed. Thomas argued that police should be able to draw blood without warrants in drunken driving cases to preserve the evidence, period. He also wrote separately to say that he thought Alito's ruling set up overly complicated guidelines for what counts as an exigent circumstance. Justice Clarence Thomas concurred in the judgement.
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California (1966), which established that police could draw blood without a warrant if they would otherwise be forced to wait so long that the evidence might be destroyed by the body's metabolic processes. To reach this conclusion, Alito drew heavily from a previous Supreme Court precedent, Schmerber v. Specifically, the justices determined that the potential dissipation of evidence of alcohol in Mitchell's bloodstream, along with other public safety needs (such as getting Mitchell to the hospital), took precedence over a warrant application and thus justified the blood draw. The plurality decision, written by Justice Samuel Alito and joined by Chief Justice John Roberts and Justices Stephen Breyer and Brett Kavanaugh, held that the blood draw is covered by the "exigent circumstances" exception to the Fourth Amendment that allows police to conduct warrantless searches in order to prevent the destruction of evidence. Mitchell challenged the constitutionality of this implied consent. Drivers essentially have to consent to this search as a condition of driving legally in the state. Wisconsin has an "implied consent" law that authorizes police to draw blood from unconscious drivers if the officers have probable cause to suspect that those drivers are under the influence of drugs or alcohol. Police brought him to a hospital for a blood test, but he was unconscious by the time they arrived and thus could not consent.
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The ruling centered on a man named Gerald Mitchell, who was arrested on suspicion of drunken driving. And the Court's judgment actually dodged the major question presented by the case: Whether a state can force a citizen to consent in advance to unwarranted blood tests as a condition of driving. Wisconsin comes just three years after the Court ruled that police generally do need to get a warrant to perform blood tests if a driver does not voluntarily consent. The Supreme Court ruled today that exigent circumstances allow police to draw blood from an unconscious driver without his permission and without a warrant if the police suspect that the driver is under the influence of alcohol.
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