N.Y. County Law § 927

§ 927. General duties of district attorneys. It shall be the duty of\nthe district attorney of the respective counties of New York, Bronx,\nKings, Queens and Richmond to prosecute all crimes and offenses\ncognizable by the courts of the county for which he shall have been\nelected or appointed, except when the place of trial of an indictment is\nchanged from one county to another, it shall be the duty of the district\nattorney of the county where the indictment is found to conduct the\ntrial of the indictment so removed, but said district attorney shall\nassist in the trial of an indictment removed to his county for trial,\nupon request of the district attorney of the county wherein the\nindictment was found. He shall perform the duties prescribed in section\nseven hundred of this chapter and such other duties as are prescribed by\nlaw.\n