N.Y. FCT Law § 580-604

§ 580-604. Choice of law. (a) Except as otherwise provided in\nsubdivision (d) of this section, the law of the issuing state or foreign\ncountry governs:\n (1) the nature, extent, amount and duration of current payments under\na registered support order;\n (2) the computation and payment of arrearages and accrual of interest\non the arrearages under the support order; and\n (3) the existence and satisfaction of other obligations under the\nsupport order.\n (b) In a proceeding for arrears under a registered support order, the\nstatute of limitation of this state or of the issuing state or foreign\ncountry, whichever is longer, applies.\n (c) A responding tribunal of this state shall apply the procedures and\nremedies of this state to enforce current support and collect arrears\nand interest due on a support order of another state or a foreign\ncountry registered in this state.\n (d) After a tribunal of this state or another state determines which\nis the controlling order and issues an order consolidating arrears, if\nany, a tribunal of this state shall prospectively apply the law of the\nstate or foreign country issuing the controlling order, including its\nlaw on interest on arrears, on current and future support, and on\nconsolidated arrears.\n