Illinois v. Wardlow, 528 U.S. 119 (2000)
Illinois v. Wardlow is a foundational Fourth Amendment case clarifying what facts can amount to reasonable suspicion for a brief investigatory stop under Terry v.
Does an individual's unprovoked flight upon noticing police officers in a high-crime area create reasonable suspicion under the Fourth Amendment sufficient to justify a Terry stop?
Under Terry v. Ohio, an officer may conduct a brief investigatory stop when the officer has reasonable, articulable suspicion, based on the totality of the circumstances, that criminal activity may be afoot. Factors relevant to reasonable suspicion include a suspect's evasive or nervous behavior and the characteristics of the location, such as whether it is a high-crime area. Mere presence in a high-crime area, or refusal to cooperate with police, without more, is insufficient. However, unprovoked headlong flight upon noticing police is a pertinent factor that, taken together with context, can establish reasonable suspicion. If a stop is lawful, the officer may conduct a limited protective frisk for weapons when the officer reasonably believes the person is armed and dangerous.
Yes. Unprovoked flight upon noticing police in a high-crime area gives rise to reasonable suspicion justifying a Terry stop. The Supreme Court reversed the Illinois Supreme Court and remanded.
Wardlow is central to Fourth Amendment doctrine on stops and frisks. It instructs that reasonable suspicion is a practical, commonsense standard allowing officers to consider location and behavior together; it also clarifies that while presence in a high-crime area alone is not enough, active, unprovoked flight powerfully supports reasonable suspicion. For students and practitioners, the case shapes how to argue and analyze stop cases: identify all contextual factors, assess the quality of the evasive behavior, and avoid bright-line rules. Wardlow also frames ongoing debates about the scope and propriety of the "high-crime area" factor, policing in marginalized communities, and how ambiguous conduct should be treated under Terry.