N.M. Stat. § 22-11-21.1
Commencing on July 1, 1983, each local administrative unit shall, solely for the purpose of compliance with Section 414(h) of the Internal Revenue Code, pick up, for the purposes specified in that section, member contributions required by Subsection A of Section 22-11-21 NMSA 1978 for all annual salary earned by the member. Member contributions picked up under the provisions of this subsection shall be treated as local administrative unit contributions for purposes of determining income tax obligations under the Internal Revenue Code; however, such picked-up member contributions shall be included in the determination of the member's gross annual salary for all other purposes under federal and state laws. Members' contributions picked up under this section shall continue to be designated member contributions for all purposes of the Educational Retirement Act and shall be considered as part of the member's annual salary for purposes of determining the amount of the member's contribution. The provisions of this section are mandatory, and the member shall have no option concerning the pickup or to receive the contributed amounts directly instead of having them paid by the local administrative unit to the educational retirement system.
NMS § 22-11-21.1