35 ILCS 200/16-125
In counties with 3,000,000 or more inhabitants, complaints filed with the board of appeals (until the first Monday in December 1998 and the board of review beginning the first Monday in December 1998 and thereafter) shall be classified by townships. All complaints shall be docketed numerically, in the order in which they are presented, as nearly as possible, in books or computer records kept for that purpose, which shall be open to public inspection. The complaints shall be considered by townships until they have been heard and passed upon by the board. After completing final action on all matters in a township, the board shall transmit such final actions to the county assessor.
A hearing upon any complaint shall not be held until the taxpayer affected and the county assessor have each been notified and have been given an opportunity to be heard. All hearings shall be open to the public and the board shall sit together and hear the representations of the interested parties or their representatives. An order for a correction of any assessment shall not be made unless both commissioners of the board, or a majority of the members in the case of a board of review, concur therein, in which case, an order for correction shall be made in open session and entered in the records of the board. When an assessment is ordered corrected, the board shall transmit a computer printout of the results, or make and sign a brief written statement of the reason for the change and the manner in which the method used by the assessor in making the assessment was erroneous, and shall deliver a copy of the statement to the county assessor. Upon request the board shall hear any taxpayer in opposition to a proposed reduction in any assessment.
The board may destroy or otherwise dispose of complaints and records pertaining thereto after the lapse of 5 years from the date of filing.
35 ILCS 200/16-125