Police had two warrants to arrest Delap. They went to what someone had told them was his address, and someone they thought was Delap ran from them toward the back door of the residence. They chased him, prevented him from closing the door, and arrested him.
Though the court granted review of this case to address an issue related to hot pursuit, it now holds the rule of Payton v. New York, 445 U.S. 573 (1980), is sufficient to decide it. That case says police can enter a house to arrest a person they think lives there, if they have an arrest warrant. There’s a live question about just what “think” means here–do the police need probable cause to believe the subject of the warrant lives at the address, or something less?–but the court doesn’t address it, because the parties didn’t argue it. So, the five-justice majority says under any potentially applicable standard, the cops had a good enough reason to think Delap lived in the house. The opinion decides nothing except the outcome.
There’s also a two-justice concurrence, which says the court should address (and bless) the state’s proffered hot-pursuit justification in order to make some law it says was left unmade by the fractured decision in State v. Weber, 2016 WI 96, 372 Wis. 2d 202, 887 N.W.2d 554. Oddly enough the opinion never says just what that unresolved question might be.