Constitution of the State of New York Art. I § 2. [Trial by jury;  how waived]

Trial by jury in all cases in which it has heretofore been guaranteed by constitutional provision shall remain inviolate forever;  but a jury trial may be waived by the parties in all civil cases in the manner to be prescribed by law.  The legislature may provide, however, by law, that a verdict may be rendered by not less than five-sixths of the jury in any civil case.  A jury trial may be waived by the defendant in all criminal cases, except those in which the crime charged may be punishable by death, by a written instrument signed by the defendant in person in open court before and with the approval of a judge or justice of a court having jurisdiction to try the offense.  The legislature may enact laws, not inconsistent herewith, governing the form, content, manner and time of presentation of the instrument effectuating such waiver.