40 ILCS 5/18-135
This system shall be administered by a Board of Trustees, of 5 members as follows: the State Treasurer, the Chief Justice of the Supreme Court, and 3 participating judges. The State Treasurer and the Chief Justice shall be ex-officio members and shall serve as trustees during their respective terms of office. Each participating judge trustee shall serve for a term of 3 years. Their successors shall be appointed by the Supreme Court not more than 3 months nor less than one month prior to the expiration of their respective terms of office.
Each trustee shall take an oath of office. The filing of a certified copy of the oath with the secretary of the board shall qualify the person as a trustee. The oath shall state that the person will diligently and honestly administer the affairs of the retirement system, and will not knowingly violate or wilfully permit any of the provisions of this Article to be violated.
A participant trustee shall be disqualified as a trustee immediately upon termination of employment as a judge. The vacancy so created shall be filled for the unexpired term by the Supreme Court.
Each trustee shall have one vote on all actions of the board and at least 3 concurring votes shall be necessary for any action by the board at any meeting. No decision or action shall become effective unless presented and so approved by the board.
40 ILCS 5/18-135