N.Y. Tax Law § 1256
Every city, county and school district shall cooperate with the state tax commission to enable it to carry out its duties under articles twenty-eight and twenty-nine of this chapter. Every such locality shall furnish to such commission those returns, reports and other information which the tax commission deems necessary to carry out such duties, except that cities having a population of one million or more, may, in their discretion, furnish instead copies of such returns, reports and other information. Such copies shall be furnished at the tax commission's expense, such expenses to be charged to the cost of administration. Notwithstanding any other law to the contrary, the duty to furnish returns, reports and other information or copies thereof shall apply to those returns and reports filed under taxes authorized under chapter eight hundred seventy-three of the laws of nineteen hundred thirty-four, as amended, chapter three hundred forty-one of the laws of nineteen hundred forty-six, as amended, article two-B of the general city law and chapter two hundred seventy-eight of the laws of nineteen hundred forty-seven, as amended, and to such other information which is relevant to the duties of the tax commission under such articles twenty-eight and twenty-nine.
N.Y. Tax Law § 1256