606:7 Waiver of Jury Trial in Certain Cases. – Any defendant in the superior court in a criminal case other than a capital case may, if he shall so elect, when called upon to plead, or later and before a jury has been impanelled to try him, waive his right to trial by jury by signing a written waiver thereof and filing the same with the clerk of the court, whereupon he shall be tried by the court instead of by a jury, but not, however, unless all the defendants, if there are 2 or more to be tried together for the same offense, shall have exercised such election before a jury has been impanelled to try any of the defendants. In every such case the court shall have jurisdiction to hear and try the case and render judgment and sentence thereon. Source. 1933, 96:1. RL 428:15.
New Hampshire Legal Code