NISI PRIUS, in English law, a term used to denote generally all actions tried before judges of the king’s bench division. For the history and meaning of this term see Assize. As a rule actions only are tried at nisi prius, and a judge is said to sit at nisi prius when he sits, usually in the king’s bench division, for the trial of actions. By a resolution passed by the judges of the king’s bench division in 1894 it was declared of the utmost importance that there should be at least three courts of nisi prius sitting continuously throughout the legal year—one for special jury causes, one for common jury causes, and one for causes without juries (see the Annual Practice).
Nisi Prius Record was before the Judicature Acts the name of the formal copy of proceedings showing the history of the case up to the time of trial. After the trial it was endorsed with the postea, showing the result of the trial, and delivered by the officer of the court to the successful party, whose possession of the postea was his title to judgment. Since the Judicature Acts there is no nisi prius record in civil actions, the nearest approach to it being the deposit of copies of the pleadings for the use of the judge, and there is no postea, the certificate of the associate or master as to the result of the trial superseding it.