N.M. Stat. § 66-6-36
To the extent permitted by the laws of the United States and by treaties entered into by the United States, the secretary may require all amounts due under the Motor Vehicle Code [66-1-1 NMSA 1978] or the Motor Transportation Act [Chapter 65, Articles 1, 3 and 5 NMSA 1978] to be paid in currency of the United States. To the extent the secretary permits or is required to permit payment of amounts due under the Motor Vehicle Code or the Motor Transportation Act to be made in foreign currency, the secretary after consultation with the secretary of finance and administration shall establish a procedure for selecting an appropriate exchange rate to be used in determining the amount due expressed in the foreign currency. The secretary may require, as a condition for accepting payment in a foreign currency, that any cost incurred or to be incurred by the department in converting the currency be added to the amount due. Amounts received by the department to defray the cost of converting currency are appropriated to the department for that purpose.
NMS § 66-6-36