70 ILCS 1210/14
The board shall investigate the efficiency of all officers and employees and of all groups of officers and employees in the classified service and shall report to each officer, board or other authority in charge of any office or department of the park district its findings and recommendations relative to increasing efficiency and economy therein. In case the recommendations made by the board are not carried into effect within a reasonable time, or in case of a difference of opinion with reference to such findings or recommendations between the board and the officer, or authority in charge of an office or department concerned in any such findings or recommendations, the report, accompanied by a note of the relevant facts shall be transmitted to the park commissioners by the board. The superintendent of employment shall investigate the enforcement of this act and of the rules of the board, the conduct of the appointees in the classified service and the methods of administration therein, and may investigate the nature, tenure and compensation of all offices and places in the civil service of the park district. In the course of such investigation said superintendent shall have power to administer oaths and to secure by subpoena both the attendance and testimony of witnesses and the production of books and papers.
70 ILCS 1210/14