The director of the department of corrections, subject to the provisions of chapter 4 of Title 36, shall be the appointing authority for all employees of the department, and he or she may assign this function to those subordinate officers and employees that may to him or her seem feasible or desirable. Notwithstanding any law to the contrary, the director shall appoint the assistant directors in charge of the divisions of the department created pursuant to § 42-56-4, as amended. The assistant director, institution/operations, the assistant director, rehabilitative services, and the assistant director, administration, shall be in the unclassified service, shall serve at the pleasure of the director, and shall be subject to the authority and supervision of the director who may assign to them those tasks and functions that the director deems appropriate in order to ensure the proper management and administration of the department.