Okla. Admin. Code § 775:15-3-2
It is the determination of the Board to use the Secretary-Treasurer's professional knowledge, training and experience in the investigation of complaints presented to the Board. In the event the Secretary-Treasurer is unable to participate in the investigation, for any reason, the President of the Board shall designate another Board member to assist in the investigation. The Secretary-Treasurer shall not participate in any other capacity in any hearing concerning a matter investigated by the agency for possible disciplinary action. No person designated to substitute for the Secretary-Treasurer in an investigation shall participate in any other capacity in an administrative proceeding. The President of the Board shall, as needed, request from the Office of the Governor the appointment of a pro-tempore Board member for any recused Board member.
Okla. Admin. Code § 775:15-3-2