40 ILCS 5/22-228
All moneys ordered to be paid from the pension fund shall be paid by the treasurer or assistant treasurer of said Board of Trustees only upon warrants signed by the president or vice president of the said Board and countersigned by the secretary or assistant secretary thereof. No warrant shall be drawn except by order of the Board of Trustees and duly entered in the records of the proceedings of the Board of Trustees.
In case the pension fund or any part thereof shall be deposited in any savings and loan association or bank or loaned, all interest on money which may be paid on account of any such loan or deposit shall belong to and constitute a part of such fund. The treasurer shall have no power to loan or deposit such fund or any part thereof unless authorized by the Board of Trustees.
40 ILCS 5/22-228