If the police fears for their safety they move on to the next step, to frisk the person for any weapons or other illegal contraband.
The requirement of "reasonable suspicion" arose out of Terry v. Ohio (1968). This case changed policing because, before it, police officers needed "probable cause" to stop someone, meaning that the officer needed sufficient information to believe that the person had committed or was about to commit a crime.
Twenty years later, after Terry v. Ohio, the cases of Floyd, et al. v. The city of New York, et al. and Daniels, et al. v. The city of New York, et al. once again questions the constitutionality of the manner in which "Terry" stops are done in New York City. In both cases, the Plaintiffs sued the City of New York alleging that the New York Police Department Has breached the Fourth and Fourteenth Amendments. The analysis of both instances brought out certain similarities on how the police violated the Constitution. The judge in the two cases was the same, Justice Scheindlin. The Plaintiffs in both actions claimed that the police officers targeted a particular race without having probable cause of suspicion enough to suspect some of any possible criminal involvement. Fourth Amendment has been systematically violated as the law enforcement officers have consistently mishandled Americans privacies and aspect of security.
The stop and frisk policy, of being stopped if a person looks reasonably suspicion is not the central issue. The main issue is how police officers are applying the policy to civilians. Police officers are only to stop a person if they look reasonably suspicious of being involved in criminal activity not based on their race or physical appearance.