The powers and duties of the sheriff's office merit commission shall be as follows:
(1) To adopt rules not inconsistent with sections 23-1721 to 23-1736 for the examination and selection of persons to fill the offices and positions in the classified service which are required to be filled by appointment and for the selection of such persons to be employed in the classified service of the office of the sheriff;
(2) To supervise the administration of the merit system rules, hold examinations from time to time after giving notice thereof, prepare and keep an eligibility list of persons passing such examinations, and certify the names of persons thereon to the sheriff;
(3) To investigate, by itself or otherwise, the enforcement of sections 23-1721 to 23-1736 and of its own rules and the action of appointees in the classified service. In the course of such investigation, the commission, or its authorized representative, shall have the power to administer oaths, and the commission shall have power, by subpoena, to secure both the attendance and testimony of witnesses and the production of books and papers relevant to such investigation;
(4) To provide, through the purchasing department of the county, all needed supplies for the use of the commission;
(5) To classify deputy sheriffs and subdivide them into groups according to rank and grade based upon the duties and responsibilities of such positions. The commission shall recommend to the county board salaries which are uniform for each group of the classified service and comparable to those of comparable counties in this section of the United States; and
(6) To perform such other duties as may be necessary to carry out sections 23-1721 to 23-1736.