N.M. Admin. Code § 20.1.9.21
The hearing officer may allow the record to remain open for a reasonable period of time following conclusion of the hearing for written submission of additional evidence, comments arguments, and proposed statements of reasons. The hearing officer's determination regarding post-hearing submissions shall be announced at the conclusion of the hearing. In considering whether the record will remain open, the hearing officer shall consider the reasons why the material was not presented during the hearing, the significance of material to be submitted, and the necessity for a prompt decision. If the record is kept open, the hearing officer shall determine and announce the subject(s) on which submittals will be allowed and the deadline for filing the submittals.
N.M. Admin. Code § 20.1.9.21