40 ILCS 5/12-156
A board composed of 7 members shall constitute a Board of Trustees authorized to carry out the provisions of this Article. Such Board of Trustees shall be known as the Retirement Board of the Park Employees' and Retirement Board Employees' Annuity and Benefit Fund.
Three members of such board shall be appointed by the board of park commissioners for terms of 3 years. Four members of such board shall be elected from among the employees for terms of 4 years who shall serve until their respective successors have been elected and have qualified.
The members of the board of a fund holding office at the time this Article becomes effective, including elected and appointed members, shall continue in office until the expiration of their respective terms or appointments and until their respective successors are appointed or elected and have qualified. When the term of any appointed member expires, the board of park commissioners shall appoint a successor.
The board shall conduct regular elections annually under rules which shall be adopted by it for the election of successors to members of the board whose terms shall expire. All employees who are included under the provisions of this Article shall be entitled to vote. The ballots shall be of secret character.
Each person elected or appointed to membership upon the board shall take a written oath of office that he will, so far as it devolves upon him, diligently and honestly administer the affairs of the office to which he was elected or appointed and that he will not knowingly violate or wilfully permit to be violated any of the provisions of law applicable under this Article. Such oath shall be subscribed by the person making it, and certified to by the officer before whom it is taken, and deposited with the custodian of the fund. Anyone after appointment or election shall be deemed to have qualified for membership on the board when such certificate is deposited with the custodian of the fund.
40 ILCS 5/12-156