In United States v. Johnson, No. 23-4255 (4th Cir. 2025), the U.S. Court of Appeals for the Fourth Circuit addressed a key Fourth Amendment issue: whether a warrantless dog sniff at the front door of an apartment, conducted in the hallway of a multi-unit building, constitutes an unlawful search. The court held that it does not. This published decision affirms that trained narcotics-detection dogs may be used outside an apartment door—without a warrant or probable cause—so long as the hallway is a common area not subject to the exclusive control of the resident. Case Background Law enforcement suspected Eric Tyrell [...]