Which court decision established the stop-and-frisk exception?

• A. Duncan v. Louisiana
• B. Terry v. Ohio
• C. Mapp v. Ohio
• D. Brown v. Board of Education

Answer: (B)

The stop-and-frisk concept centers on the Fourth Amendment allowance for a brief, protective police action based on reasonable suspicion. Terry v. Ohio established this rule: a law enforcement officer may stop a person and briefly detain them if there are specific, articulable facts indicating possible criminal activity, and may perform a limited frisk for weapons if there is a reasonable belief that the person is armed and dangerous. This creates a two-step standard that prioritizes officer safety while imposing limited intrusion on individual rights, distinguishing a mere encounter from a full arrest or search.

That decision is not about jury trials, the exclusionary rule, or school segregation. Duncan v. Louisiana deals with the right to a jury trial; Mapp v. Ohio extends the exclusionary rule to the states; Brown v. Board of Education addresses desegregation in public schools.