70 ILCS 1710/6
Commissioners appointed by the Governor prior to the effective date of this amendatory Act of 1975 shall serve the balance of 6-year terms to which they were appointed. Subsequent to the effective date of the amendatory Act of 1975, the Governor shall make no appointments of Commissioners to new terms or to fill vacancies until such time as the total number of Commissioners so appointed by the Governor and then holding valid terms on the Commission shall be reduced by expiration of terms, or attrition, or otherwise, to 7 in number. Thereafter, Commissioners shall be appointed by the Governor to fill terms expiring in such manner as to maintain the number of Governor-appointed Commissioners at 8 in number. Commissioners so appointed after the effective date of the amendatory Act of 1975 shall serve for terms of 4 years and until successors are appointed and qualified, such terms to commence on October 1 of the year in which such Commissioners are each first appointed, provided that initial appointments of Commissioners by the Governor pursuant to revisions enacted by the amendatory Act of 1975 shall be made for terms of one year, 2 years, 3 years, or 4 years (as the Governor shall determine in the case of each appointment) in order to establish a pattern of staggered terms of office in which the terms of 2 Governor-appointed Commissioners expire in each calendar year.
Commissioners appointed or selected by means other than appointment by the Governor or by virtue of holding an elective or appointive position separate from the Commission shall serve at the pleasure of the appointing or selecting agency, provided they remain qualified for service as a Commissioner, and provided further that each person or authority making such an appointment shall review the advisability of changing the person so appointed or selected at least every 2 years.
If a vacancy occurs by death, resignation or otherwise among Governor-appointed Commissioners, the Governor shall fill the vacancy by an appointment for the unexpired term, subject to the prohibition set forth above precluding the filling of vacancies, after the effective date of the amendatory Act of 1975, until the number of Governor-appointed Commissioners is reduced to 7 in number. In the event of a vacancy by reason of death, resignation or otherwise among Commissioners selected by means other than appointment by the Governor or by virtue of holding an elective or appointive position separate from the Commission, the proper selecting authority shall make a replacement appointment within a reasonable time period not exceeding 90 days.
70 ILCS 1710/6