Justices ruled police officers can perform a blood test on a DUI suspect without a warrant, providing that person is unconscious.

The ruling gives officers the legal right to draw blood from an unconscious person who’s suspected of drinking or doing drugs. Otherwise, they’re required to get permission — or a warrant, if the suspect refuses.

The precedent-setting decision came about from a Wisconsin case in which a DUI suspect was tested after he’d been knocked out in a crash.

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