40 ILCS 5/22-403
Any tax heretofore or hereafter levied for the benefit or purposes of any such pension fund by the tax-levying body authorized by the law creating such fund to levy such tax, and any payment or contribution to such fund made by the State, or by any county, city, town, municipal corporation or body politic and corporate located in the State, is hereby declared to be so levied or so contributed for governmental purposes under such law, and not for the corporate purposes of such tax-levying body, or of the State, or of any county, city, town, municipal corporation or body politic and corporate of the State, irrespective of the nature or character of the duties performed or services rendered by any employee member of any such pension fund. This section shall not apply to any tax levies heretofore adjudicated by the Supreme Court of this State. Any pension payable under any law hereinbefore referred to shall not be construed to be a legal obligation or debt of the State, or of any county, city, town, municipal corporation or body politic and corporate located in the State, other than the pension fund concerned, but shall be held to be solely an obligation of such pension fund, unless otherwise specifically provided in the law creating such fund.
40 ILCS 5/22-403