10 U.S.C. § 8037: Assistant Chiefs of Naval Operations

(a) There are Assistant Chiefs of Naval Operations in the Office of the Chief of Naval Operations, detailed by the Secretary of the Navy from officers on the active-duty list of the Navy and officers on the active-duty list of the Marine Corps. The Secretary of the Navy shall prescribe the number of Assistant Chiefs of Naval Operations in accordance with section 8036(a) of this title. (b) The Assistant Chiefs of Naval Operations shall perform such duties as the Secretary of the Navy prescribes.