50 ILCS 315/2

All elected or appointed officials of units of local government, and clerks of the circuit courts, authorized by law to collect fees which collection is not prohibited by Section 9 of Article VII of the Constitution, shall deposit all such collected fees upon receipt with the county treasurer or treasurer of such other unit of local government, as the case may be, except as otherwise provided by law; and except that such officials may maintain overpayments, tax redemptions, trust funds and special funds as provided for by law or local ordinance.