Mass. Gen. Laws ch. 19 § 3
The commissioner shall appoint, with the approval of the secretary of health and human services, a person qualified to serve as deputy commissioner of mental health. Said deputy commissioner shall perform such duties as the commissioner may determine and shall, in the case of a vacancy in the office of the commissioner, and during said commissioner's absence or disability, exercise the powers and perform the duties of the office of the commissioner. Said deputy commissioner may be allowed such professional affiliations as the commissioner approves, subject to the provisions of chapter two hundred and sixty-eight A.
The deputy commissioner shall have such educational qualifications and such administrative and other experience, including education or experience in a field related to human services, as the commissioner determines are necessary for the performance of the duties of the deputy commissioner. The commissioner or a deputy commissioner shall be a diplomate in psychiatry of the American Board of Psychiatry and Neurology, Inc.
Mass. Gen. Laws ch. 19, § 3