65 ILCS 5/8-1-13
Every municipality holding in its treasury funds which are set aside for use for particular purposes, but which are not immediately necessary for those purposes, by ordinance, may use those funds, or any of them, in the purchase of tax anticipation warrants issued by the municipality possessing the funds against taxes levied by that municipality. These warrants shall bear interest not to exceed the maximum rate authorized by the Bond Authorization Act, as amended at the time of the making of the contract. All interest upon these warrants, and all money paid in redemption of these warrants or received from the resale thereof, shall at once be credited to and placed in the particular fund used to purchase the specified warrants.
However, a municipality so using any of its funds for the purchase of such tax anticipation warrants shall not apply to the payment thereof while so held by it any taxes against and in anticipation of which the warrants were issued, unless and until all warrants and the interest thereon, issued by that municipality against and in anticipation of the same taxes and sold to other purchasers have been first paid or money sufficient for the payment thereof has been deposited in the municipal treasury as a special fund to be used solely for the purpose of paying to the other purchasers the warrants and the interest thereon when presented. Nothing contained in this section shall prevent the resale or reissue of any warrants as provided in Section 8-1-14.
Likewise, every municipality by ordinance may use the money in those funds in the purchase of bonds issued by the municipality, possessing the funds and representing the obligation and pledging the credit of that municipality, or bonds and other interest bearing obligations of the United States or of the State of Illinois. All interest upon these bonds or obligations and all money paid in redemption of these bonds or obligations or realized from the sale thereof, if afterwards sold, shall at once be credited to and placed in the particular fund used to purchase specified bonds or obligations.
With respect to instruments for the payment of money issued under this Section either before, on, or after the effective date of this amendatory Act of 1989, it is and always has been the intention of the General Assembly (i) that the Omnibus Bond Acts are and always have been supplementary grants of power to issue instruments in accordance with the Omnibus Bond Acts, regardless of any provision of this Act that may appear to be or to have been more restrictive than those Acts, (ii) that the provisions of this Section are not a limitation on the supplementary authority granted by the Omnibus Bond Acts, and (iii) that instruments issued under this Section within the supplementary authority granted by the Omnibus Bond Acts are not invalid because of any provision of this Act that may appear to be or to have been more restrictive than those Acts.
65 ILCS 5/8-1-13