The main difference between the two is that false arrest requires an arrest, but, false imprisonment only requires unlawful detention. False imprisonment occurs when one person unlawfully restricts another's freedom of movement.Court concluded as a matter of law that officer had probable cause to arrest plaintiff). 3. False arrest requires an arrest, but, false imprisonment only requires unlawful detention. In a suit for false imprisonment, a record of conviction for the same offense for which the arrest was made is inadmissible. In that case, one individual holds another against their will or takes them into custody without consent or legal authority to do so. A police officer commits false arrest if they take into custody or otherwise detain another person without consent or legal justification. The torts of false arrest and false imprisonment are largely synonymous. False arrest occurs when someone makes an arrest, and the facts of the "crime" don't fit the elements in the statute. The defendant filled out an incident report about the assault but did not assist in applying for the arrest warrant.