70 ILCS 3605/21
Members of the Board shall hold office until their respective successors have been appointed and have qualified. Any member may resign from his or her office, to take effect when his or her successor has been appointed and has qualified. The Governor and the Mayor, respectively, may remove any member of the Board appointed by him or her in case of incompetency, neglect of duty, or malfeasance in office. They may give him or her a copy of the charges against him or her and an opportunity to be publicly heard in person or by counsel in his or her own defense upon not less than 10 days' notice. The Governor may remove any member in response to a summary report received from the Executive Inspector General in accordance with Section 20-50 of the State Officials and Employees Ethics Act, provided he or she has an opportunity to be publicly heard in person or by counsel prior to removal. In case of failure to qualify within the time required, or of abandonment of his or her office, or in case of death, conviction of a crime or removal from office, his or her office shall become vacant. Each vacancy shall be filled for the unexpired term by appointment in like manner, and with like regard as to the place of residence of the appointee, as in case of expiration of the term of a member of the Board.
70 ILCS 3605/21