John Marshall Harlan II

“ The State of New York has made a deliberate effort to deal with the complex problem of on-the-street police work. Without giving carte blanche to any particular verbal formulation, we should, I think, where relevant, indicate the extent to which that effort has been constitutionally successful. The core of the New York statute is the permission to stop any person reasonably suspected of crime. Under the decision in Terry a right to stop may indeed be premised on reasonable suspicion and does not require probable cause, and hence the New York formulation is to that extent constitutional. ”

“ Probable cause to arrest means evidence that would warrant a prudent and reasonable man (such as a magistrate, actual or hypothetical) in believing that a particular person has committed or is committing a crime. [3] Officer Lasky had no extrinsic reason to think that a crime had been or was being committed, so whether it would have been proper to issue a warrant depends entirely on his statements of his observations of the men. ”

“ It was clear that the officer had to act quickly if he was going to act at all, and, as stated above, it seems to me that where immediate action is obviously required, a police officer is justified in acting on rather less objectively articulable evidence than when there is more time for consideration of alternative courses of action. ”