Warrantless Stops 101 -- Was the Stop Supported by Reasonable Suspicion?

In my first Warrantless Stops 101 post, I offered these basic questions to frame the analysis: Did a seizure occur? If so and it was a stop, was it supported by reasonable suspicion or other valid basis? If reasonable suspicion supported the stop, was the officer’s subsequent conduct sufficiently limited in scope? If the seizure was an arrest, was it supported by probable cause? If the arrest was supported by probable cause, was the search permissible? My first post focused on whether a seizure occurred. This one looks at whether the stop was supported by reasonable suspicion. If so, the stop itself is constitutional and the only remaining issue is whether the officer’s conduct exceeded the scope of the stop, a topic I’ll take up in a later post. Reasonable Suspicion The black letter law is that an officer may make an investigatory stop when the officer “observes unusual conduct which leads him reasonably to conclude in light of his experience that criminal activity may be afoot.” Terry v. Ohio, 392 U.S. 1, 30 (1968). This standard is known by the shorthand, “reasonable suspicion,” although other terms such as “articulable suspicion” are sometimes used. The standard requires the officer to articulate more than an “inchoate and unparticularized suspicion or ‘hunch.’” Id. at 27. The determination is made from the officer’s perspective; basically, this means that the officer may make “inferences and deductions that might well elude an untrained person” and the evidence should be evaluated “as understood by those versed in [...]