Unlawful imprisonment

False imprisonment occurs when a person is restricted in their personal movement within any area without justification or consent. Actual physical restraint is not necessary to a false imprisonment case. False imprisonment is a common-law felony and a tort. It applies to private as well as governmental detention. When it comes to public police, the proving of false imprisonment is sufficient to obtain a writ of habeas corpus.

As to what constitutes imprisonment, see Imprisonment.

The following are false imprisonment scenarios.

Under United States law, the police have the right to detain someone if they have probable cause to believe a crime has been committed, and that the person is so involved, or if the officer has reasonable suspicion, based on specific and articulable facts and inferences, that the person has been, is, or is about to be, engaged in a criminal activity.

Many jurisdictions of the United States recognize the common law shopkeeper's privilege, under which a person is allowed to detain a suspected shoplifter on store property for a reasonable period of time, with cause to believe that the person detained in fact committed, or attempted to commit theft of store property. The shopkeeper is allowed to ask the suspected individual to demonstrate that the suspect has not been shoplifting. The purpose of the shopkeeper's privilege is to find out if the individual is shoplifting and can the item be reclaimed. The shopkeeper's privilege, although recognized in most jurisdictions, is not as broad a privilege as that of a police officer's, and therefore one must pay special attention to the temporal element – that is, the shopkeeper may only detain the suspected criminal for a relatively short period of time. This is similar to a general right in many jurisdictions of citizen's arrest of suspected criminals by the public in limited circumstances.

This privilege has been justified by the very practical need for some degree of protection for shopkeepers in their dealings with suspected shoplifters. Absent such privilege, a shopkeeper would be faced with the dilemma of either allowing suspects to leave without challenge or acting upon his suspicion and risk making a false arrest.

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