Whether police may, on reasonable suspicion but without probable cause, take a person involuntarily to a police station and detain him there for custodial interrogation.
Holding
No. A seizure that takes a person into custody, transports him to the station, and confines him for interrogation is sufficiently like a traditional arrest that it requires probable cause.
Reasoning
The Fourth Amendment applies to state officers through the Fourteenth Amendment, and Dunaway was seized when police involuntarily took him to the station. The State conceded that officers lacked probable cause before he made his incriminating statements. The constitutional question therefore turned on whether this seizure could be justified by something less than probable cause.
Terry v. Ohio permits a narrowly limited exception for a brief, on-the-scene stop and protective frisk based on reasonable suspicion. That exception rests on the comparatively modest nature and tightly confined purpose of a Terry stop. Terry and its successors do not authorize the substantially greater intrusion of taking a suspect from a home or other location to a stationhouse for custodial questioning.
Dunaway’s treatment was, in practical terms, indistinguishable from an arrest. He was taken by police car to headquarters, placed in an interrogation room, never told he was free to leave, and would have been physically restrained if he tried to depart. The absence of formal booking, an announced arrest, or an arrest record could not turn this custodial seizure into the kind of brief encounter permitted by Terry.
The Court rejected a general balancing rule allowing stationhouse interrogation whenever police have reasonable suspicion. Such an exception would threaten to swallow the traditional probable-cause rule and would leave officers to balance numerous competing factors in the course of investigating crime. Probable cause supplies the familiar, workable constitutional line that protects personal privacy and security.
Davis v. Mississippi and Brown v. Illinois reinforced the conclusion. Both rejected the proposition that detention at the investigative stage is exempt from Fourth Amendment limits. Police may not conduct an investigatory seizure in the hope that questioning will uncover evidence sufficient to establish probable cause.