70 ILCS 2605/4.14
No employee in the classified civil service of the sanitary district shall be involuntarily demoted or discharged except for cause, upon written charges, and after an opportunity to be heard in his own defense. For discharge actions, such charges shall be filed with the civil service board within 30 days from the date of suspension under the charges, and the charges shall be promptly investigated by or before the civil service board, or by or before some officer or officers appointed by the civil service board to conduct such investigation. Both involuntary demotion and discharge hearings shall be public and the employee shall be entitled to call witnesses in his or her defense and to have the aid of counsel. Such hearings shall take place within 120 days after charges are filed against the employee, unless the civil service board continues a discharge or involuntary demotion hearing for good cause shown and with the consent of the employee. After the hearing is completed, the civil service board shall enter a finding and decision. A decision shall be deemed to have been served either when a copy of the decision is personally delivered or when a copy of the decision is deposited in the United States mail, addressed to the employee at his last known address on file with the human resources department. The finding and decision of the civil service board or of such investigating officer or officers, when approved by said civil service board, shall be final, except for the judicial review thereof as herein provided, and shall be certified to the appointing officer, and shall be forthwith enforced by such officer. Nothing in this Act shall limit the power of any officer to suspend a subordinate for a reasonable period not exceeding thirty days; however, if charges are filed against a suspended employee, the suspension shall be extended until the civil service board enters its finding and decision regarding the charges unless prior to this time the board enters an order approving an agreement between the sanitary district and the employee that the suspension should terminate at an earlier date. Every such suspension shall be without pay: Provided, however, that the civil service board shall have authority to investigate every such suspension and, in case of its disapproval thereof, it shall have power to restore pay to the employee so suspended. For discharge actions, if the civil service board enters a finding and decision denying discharge, the employee shall be returned to the classification held at the time charges were filed. For involuntary demotion actions, if the civil service board enters a finding and decision granting an involuntary demotion, the employee shall be demoted to the employee's most recent former classification. In the course of any investigation provided for in this Act, each member of the civil service board and any officer appointed by it shall have the power to administer oaths and shall have power to secure by its subpoena both the attendance and testimony of witnesses and the production of books and papers.
Either the sanitary district or the employee may file a written petition for rehearing of the finding and decision of the civil service board within 21 calendar days after the finding and decision are served as provided in this Section. The petition shall state fully the grounds upon which application for further investigation and hearing is based. If a petition is denied by the civil service board, the decision shall remain in full force and effect and any further appeal by either party shall be in accordance with the provisions of the Administrative Review Law.
The provisions of the Administrative Review Law, and all amendments and modifications thereof, and the rules adopted pursuant thereto, shall apply to and govern all proceedings for the judicial review of final administrative decisions of the civil service board hereunder. The term "administrative decision" is defined as in Section 3-101 of the Code of Civil Procedure.
70 ILCS 2605/4.14