30 ILCS 230/2a
Every officer, board, commission, commissioner, department, institute, arm, or agency to whom or to which this Act applies is to notify the State Treasurer as to money paid to him, her, or it under protest as provided in Section 2a.1, and the Treasurer is to place the money in a special fund to be known as the protest fund. At the expiration of 30 days from the date of payment, the money is to be transferred from the protest fund to the appropriate fund in which it would have been placed had there been payment without protest unless the party making that payment under protest has filed a complaint and secured within that 30 days a temporary restraining order or a preliminary injunction, restraining the making of that transfer and unless, in addition, within that 30 days, a copy of the temporary restraining order or preliminary injunction has been served upon the State Treasurer and also upon the officer, board, commission, commissioner, department, institute, arm, or agency to whom or to which the payment under protest was made, in which case the payment and such other payments as are subsequently made under notice of protest, as provided in Section 2a.1, by the same person, the transfer of which payments is restrained by such temporary restraining order or preliminary injunction, are to be held in the protest fund until the final order or judgment of the court. The judicial remedy herein provided, however, relates only to questions which must be decided by the court in determining the proper disposition of the moneys paid under protest. Any authorized payment from the protest fund shall bear simple interest at a rate equal to the average of the weekly rates at issuance on 13-week U.S. Treasury Bills from the date of deposit into the protest fund to the date of disbursement from the protest fund. In cases involving temporary restraining orders or preliminary injunctions entered March 10, 1982, or thereafter, pursuant to this Section, when the party paying under protest fails in the protest action the State Treasurer shall determine if any moneys paid under protest were paid as a result of assessments under the following provisions: the Municipal Retailers' Occupation Tax Act, the Municipal Service Occupation Tax Act, the Municipal Use Tax Act, the Municipal Automobile Renting Occupation Tax Act, the Municipal Automobile Renting Use Tax Act, Section 8-11-9 of the Illinois Municipal Code, the Tourism, Conventions and Other Special Events Promotion Act of 1967, the County Automobile Renting Occupation Tax Act, the County Automobile Renting Use Tax Act, Section 5-1034 of the Counties Code, Section 5.01 of the Local Mass Transit District Act, the Downstate Public Transportation Act, Section 4.03 of the Regional Transportation Authority Act, subsections (c) and (d) of Section 201 of the Illinois Income Tax Act, Section 2a.1 of the Messages Tax Act, Section 2a.1 of the Gas Revenue Tax Act, Section 2a.1 of the Public Utilities Revenue Act, and the Water Company Invested Capital Tax Act. Any such moneys paid under protest shall bear simple interest at a rate equal to the average of the weekly rates at issuance on 13-week U.S. Treasury Bills from the date of deposit into the protest fund to the date of disbursement from the protest fund.
It is unlawful for the Clerk of a court, a bank or any person other than the State Treasurer to be appointed as trustee with respect to any purported payment under protest, or otherwise to be authorized by a court to hold any purported payment under protest, during the pendency of the litigation involving such purported payment under protest, it being the expressed intention of the General Assembly that no one is to act as custodian of any such purported payment under protest except the State Treasurer.
No payment under protest within the meaning of this Act has been made unless paid to an officer, board, commission, commissioner, department, institute, arm or agency brought within this Act by Section 1 and unless made in the form specified by Section 2a.1. No payment into court or to a circuit clerk or other court-appointed trustee is a payment under protest within the meaning of this Act.
30 ILCS 230/2a