N.Y. FCT Law § 254

§ 254. Presentation by corporation counsel, county attorney or\ndistrict attorney. (a) The family court or the appropriate appellate\ndivision of the supreme court may request the corporation counsel of the\ncity of New York or the appropriate county attorney to present the case\nin support of the petition when, in the opinion of the family court or\nappellate division such presentation will serve the purposes of the act.\nWhen so requested, the corporation counsel or county attorney shall\npresent the case in support of the petition and assist in all stages of\nthe proceedings, including appeals in connection therewith. Nothing\nherein shall be deemed to affect the provisions of section five hundred\nthirty-five of this chapter.\n (b) In all cases involving abuse, the corporation counsel of the city\nof New York and outside the city of New York, the appropriate district\nattorney shall be a necessary party to the proceeding.\n