Also known as: specific articulable facts · articulable facts · reasonable suspicion facts
Written by attorneys · grounded in primary & secondary sources — see below
Particularized observations that an officer can describe to support a reasonable suspicion that criminal activity is afoot or that a person is armed and dangerous. The facts must be concrete rather than inchoate hunches and are evaluated under the totality of the circumstances.
Officers arrest Sean Steele inside his living room on an outstanding warrant. While securing the scene they notice a partially open basement door and hear footsteps below. The officers conduct a limited sweep of the basement after noting these observations.
Officer Lewis sees Santiago Sanchez loitering after dark outside an unlocked classroom building with a large empty backpack while testing doorknobs and appearing to send text updates. The officer briefly detains Sanchez based on these observations combined with recent theft reports.
Select any source to read its text and confirm it supports the definition.
A trooper stops Sofia Stern for speeding and observes a large knife sheath on the floorboard plus furtive movements toward the passenger seat. The trooper conducts a limited search of the passenger compartment for weapons.
Police detain Scott Summers for walking late at night without identification after he refuses to provide his name. Summers challenges the stop as resting on insufficient particularized facts under the statute.
An officer stops Sierra Santos near a reported disturbance and asks for her name. Santos refuses and is arrested under a state statute requiring identification during a lawful detention.
Officers take Sabrina Shah into custody for a minor traffic violation without any facts suggesting she poses a danger or will flee. Shah challenges the arrest as exceeding the scope justified by the initial observations.
They support reasonable suspicion for a brief investigative stop or frisk but fall short of probable cause. The facts must be particularized and viewed under the totality of the circumstances.
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Yes. A series of individually innocent observations can create reasonable suspicion when taken together and interpreted through an officer's training and experience.
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They must support a reasonable belief that the area harbors an individual posing danger to officers. The sweep remains limited to spaces where a person could hide.
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No. Officers need only a particularized objective basis for suspicion. Innocent explanations do not automatically defeat reasonable suspicion under the totality test.
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…387 U. S. 523, 534-535, 536-537 (1967). And in justifying the particular intrusion the police officer must be able to point to specific and articulable facts which, taken together with rational inferences from those facts, reasonably warrant that intrusion. The scheme of the Fourth Amendment becomes meaningful only when it is assured that at…