The main difference between the two is that false arrest requires an arrest, but, false imprisonment only requires unlawful detention. Am. Complaint 161-184.Each claim is based upon facts alleging false arrest, false imprisonment, and malicious prosecution. Additionally, Plaintiff alleges related state law claims. Probable cause is a complete defense to an action alleging false arrest or false imprisonment whether brought under state law or § 1983. § 1983 and state law claims of false arrest, false imprisonment and malicious prosecution. Black's Law Dictionary defines false imprisonment as "A restraint of a person in a bounded area without justification or consent. Unlawful Imprisonment in the First Degree is a New York criminal offense imposing harsh penalties on anyone who restrains another person. Fill out the complaint form, answering all of the questions completely. Grandfather suing Nassau County police over claims of excessive force during wrongful arrest.