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 a Civil Service Commission, or of the Police Board of a city of more than 500,000 population. The term "administrative decision" is defined as in Section 3-101 of the Code of Civil Procedure.
65 ILCS 5/10-1-45