The commissioner shall appoint as many individuals as necessary to carry out the department’s responsibilities under this chapter. Such individuals shall have experience in workers’ compensation and shall hear workers’ compensation cases before the commissioner. The commissioner shall set forth the job qualification necessary to insure that each hearing officer is qualified to hear workers’ compensation cases. The salary shall be commensurate with the responsibilities and experience required. The commissioner shall, by rules adopted under RSA 541-A, strengthen the reporting structure and the role of a hearing officer; develop a code of ethics for hearings and hearing officers; develop and require at least 15 hours of continuing education on an annual basis for hearing officers; and require a minimum of an additional 15 hours of annual training and briefing with the attorney general’s staff.