By all accounts, the head nurse at the University of Utah Hospital’s burn unit was professional and restrained when she told a Salt Lake City police detective he wasn’t allowed to draw blood from a badly injured patient.

The detective didn’t have a warrant, first off. And the patient wasn’t conscious, so he couldn’t give consent. Without that, the detective was barred from collecting blood samples — not just by hospital policy, but by basic constitutional law.

Still, Detective Jeff Payne insisted that he be let in to take the blood, saying the nurse would be arrested and charged if she refused.