Also known as: reasonable articulable suspicion · articulable suspicion · reasonable suspicion · RAS · Terry suspicion
Written by attorneys · grounded in primary & secondary sources — see below
A Fourth Amendment standard requiring specific and articulable facts that, taken together with rational inferences from those facts, reasonably warrant a brief investigative detention or frisk. The standard is lower than probable cause but demands more than an inchoate hunch or unparticularized suspicion.
An officer receives an anonymous tip describing Ruby Rivera driving a specific vehicle and arriving at a particular intersection at a precise time to complete a drug transaction. The officer observes the vehicle arrive exactly as predicted and conducts a brief stop. The accurate prediction of future conduct supplies the specific and articulable facts needed to justify the detention.
Roland Rhodes is stopped on a public sidewalk after an officer demands identification under a statute requiring individuals to provide credible and reliable identification when asked. The officer lacks any facts suggesting criminal activity beyond Rhodes's presence. The absence of specific and articulable facts renders the detention unconstitutional.
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An officer stops Rebecca Ross for speeding and observes a knife on the floorboard plus erratic behavior suggesting possible weapons. The officer conducts a limited search of the passenger compartment. The observed facts provide reasonable suspicion that the suspect is armed, justifying the protective search.
An officer observes Roberto Reyes conversing with known narcotics users and reaches into his pocket without any indication of a weapon or ongoing crime. The officer finds drugs during the frisk. No specific and articulable facts supported a belief that Reyes was armed or engaged in criminal activity.
Officers detain Ralph Richardson's luggage at an airport for ninety minutes to conduct a dog sniff after observing nervous behavior and a matching drug-courier profile. No facts indicate the luggage contains contraband beyond the profile. The prolonged seizure exceeds the scope permitted by reasonable suspicion.
Federal agents arrest Ricardo Rojas under a material-witness statute solely to investigate unrelated terrorism suspicions without any facts linking him to criminal activity. The arrest is executed to hold him for questioning. The lack of specific and articulable facts showing a legitimate witness purpose invalidates the detention.
An anonymous tip can establish reasonable, articulable suspicion when it contains sufficient indicia of reliability, such as accurate predictions of the suspect's future movements that demonstrate inside knowledge of criminal activity.
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The Fourth Amendment does not require reasonable, articulable suspicion of drug activity before officers may conduct a dog sniff during a legitimate traffic stop, provided the sniff does not prolong the stop beyond the time needed to complete the original mission.
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A statute permitting detention based solely on failure to provide identification does not satisfy the reasonable, articulable suspicion requirement when officers lack objective facts indicating criminal activity.
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Reasonable, articulable suspicion requires specific facts supporting a reasonable belief that criminal activity may be afoot, while probable cause requires facts sufficient to warrant a prudent person in believing that a crime has been committed.
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…the problem is to determine what makes a frisk reasonable. If the State of Ohio were to provide that police officers could, on articulable suspicion less than probable cause, forcibly frisk and disarm persons thought to be carrying concealed weapons, I would have little doubt that action taken pursuant to such authority could be…