I don’t know that you want to see/read the caselaw on this (from 1976), it’s in the PS if you do. I’ve been a criminal defense attorney twenty-five years and I’ve been handling appeals full time for more than twenty. “Reasonable Suspicion” has always been the test for pulling over automobiles, reasonable suspicion that the person is committing, has committed or is about to commit a crime.
So in terms of the requisite police knowledge required for an intrusion, people are complaining about something that has always been true. Complaining about allowing police to stop a car based on reasonable suspicion is like complaining that water flows downhill.
P.S. Here’s the main case in NY on what level of police knowledge is required to justify each type of intrusion into people’s lives – Debour has four levels, and it is still good law.
Here is the critical paragraph (go to [*223] in Red on the linked page):
“The minimal intrusion of approaching to request information is permissible when there is some objective credible reason for that interference not necessarily indicative of criminality (People v De Bour, supra). The next degree, the common-law right to inquire, is activated by a founded suspicion that criminal activity is afoot and permits a somewhat greater intrusion in that a policeman is entitled to interfere with a citizen to the extent necessary to gain explanatory information, but short of a forcible seizure (People v Cantor, 36 NY2d, at p 114, supra.;; People v Rosemond, 26 NY2d 101; People v Rivera, 14 NY2d 441, 446, and authorities cited therein). Where a police officer entertains a reasonable suspicion that a particular person has committed, is committing or is about to commit a felony or misdemeanor, the CPL authorizes a forcible stop and detention of that person (CPL 140.50, subd 1; see Terry v Ohio, 392 US 1; People v Cantor, supra). A corollary of the statutory right to temporarily detain for questioning is the authority to frisk if the officer reasonably suspects that he is in danger of physical injury by virtue of the detainee being armed (CPL 140.50, subd 3). Finally a police officer may arrest and take into custody a person when he has probable cause to believe that person has committed a crime, or offense in his presence (CPL 140.10). This synopsis represents the gradation of permissible police authority with respect to encounters with citizens in public places and directly correlates the degree of objectively credible belief with the permissible scope of interference.”