Illinois constitution
Article IX
Section 9

(f) The State, departments, authorities, public corporations and quasi-public corporations of the State, the
State colleges and universities and other public agencies created by the State, may issue bonds or other evidences of
indebtedness which are not secured by the full faith and credit or tax revenue of the State nor required to be repaid, directly or indirectly, from tax revenue, for such purposes and in such amounts as may be authorized by law.