Michigan hospital blood results can become evidence in a DUI case even when medical personnel drew the blood for treatment before the driver was arrested. Michigan’s statutory term is operating while intoxicated, or OWI, although most people search for this issue as DUI. The prosecutor’s ability to obtain the result depends on why the blood was drawn, what happened before the hospital transport, who requested the result, and precisely what the hospital disclosed.

The controlling Michigan Supreme Court decision remains People v. Perlos. It upheld the statutory procedure in 1990. More recent Fourth Amendment law creates a principled basis for challenging the statute as unconstitutional as applied to the warrantless acquisition of private medical information and for asking the Michigan Supreme Court to reconsider Perlos. But no controlling decision has displaced Perlos. A careful defense must therefore develop the constitutional challenge while also testing whether the prosecution satisfied the statute in the first place.