Which case established the 'reasonable suspicion' standard for police stops and frisks?

• A. Terry v. Ohio (1968)
• B. United States v. Arvizu (1987)
• C. Adams v. Williams (1972)
• D. Hiibel v. Sixth Judicial District (2004)

Answer: (A)

The main concept is the police can briefly stop and frisk someone when they have reasonable suspicion of criminal activity. This rule was established by Terry v. Ohio, which allowed an officer to detain a person for a short period to investigate if they reasonably believe the person is involved in criminal activity, and to conduct a quick pat-down for weapons if the officer also believes the person may be armed and dangerous. The standard of reasonable suspicion sits between a mere hunch and probable cause, requiring specific, articulable facts available at the moment of the stop. This decision creates a limited intrusion designed to protect the officer’s safety and to allow a brief investigation without fully infringing on Fourth Amendment rights.

While other cases further develop or apply the doctrine—such as refining how to evaluate the totality of the circumstances in establishing reasonable suspicion, or addressing related issues like compelled identification—none established the initial standard itself. Terry v. Ohio is the foundational ruling that authorized stops and frisks based on reasonable suspicion.