An alibi is the plea or mode of defense under which a person on trial for a crime proves or attempts to prove that he was in another place when the alleged act was committed; as, to set up an alibi; to prove an alibi. The Criminal Law Deskbook of Criminal Procedure states: "Alibi is different from all of the other defenses...it is based upon the premise that the defendant is truly innocent.". In the Latin language "alibi" means "somewhere else."