Mark Jerome Johnson v. State of Minnesota

Summary

The court held that the constitutional rule governing criminalization of refusals to submit to warrantless blood or urine tests is substantive and applies retroactively to final convictions on collateral review. Johnson's guilty pleas did not waive his challenge because he asserted that the statute was unconstitutional as applied and therefore that the district court lacked subject-matter jurisdiction. The court reversed and remanded for individualized determinations of whether a warrant or valid warrant exception supported each conviction.