N.M. Admin. Code § 2.20.2.3
In order to ascertain the authority and legality of contracts, purchase orders, vouchers, travel vouchers and other financial commitments for departments and other state agencies, pursuant to Section 6-5-3 NMSA 1978, it is necessary to determine whether the person executing the contract has been properly delegated the authority to bind the department or state agency. In many instances there is no clear statutory power granted to an officer to sign on behalf of an agency. Generally the person who is ultimately responsible for the administration of the law has the implied power to execute legal documents for a state agency. Generally the power to execute may be delegated; however, some laws may require specific officers to execute contracts and vouchers on behalf of the agency. In such cases, no delegation is allowed by law.
N.M. Admin. Code § 2.20.2.3