New York courts have defined probable cause for an arrest as follows:

"An arrest is justified upon finding a probable cause based upon information sufficient to form a reasonable belief that a person has committed a crime."People v. Bigelow, 66 N.Y.2d 417

Determinations as to what constitutes probable cause are complex and very fact specific, since each case is different. A defendant can assert that the police did not have probable cause for an arrest by way of pre-trial motions and hearings.