605 ILCS 10/19
The Authority shall fix and revise from time to time, tolls or charges or rates for the privilege of using each of the toll highways constructed pursuant to this Act. Such tolls shall be so fixed and adjusted at rates calculated to provide the lowest reasonable toll rates that will provide funds sufficient with other revenues of the Authority to pay, (a) the cost of the construction of a toll highway authorized by joint resolution of the General Assembly pursuant to Section 14.1 and the reconstruction, major repairs or improvements of toll highways, (b) the cost of maintaining, repairing, regulating and operating the toll highways including only the necessary expenses of the Authority, and (c) the principal of all bonds, interest thereon and all sinking fund requirements and other requirements provided by resolutions authorizing the issuance of the bonds as they shall become due. In fixing the toll rates pursuant to this Section 19 and Section 10(c) of this Act, the Authority shall take into account the effect of the provisions of this Section 19 permitting the use of the toll highway system without payment of the covenants of the Authority contained in the resolutions and trust indentures authorizing the issuance of bonds of the Authority. No such provision permitting the use of the toll highway system without payment of tolls after the date of this amendatory Act of the 95th General Assembly shall be applied in a manner that impairs the rights of bondholders pursuant to any resolution or trust indentures authorizing the issuance of bonds of the Authority. The use and disposition of any sinking or reserve fund shall be subject to such regulation as may be provided in the resolution or trust indenture authorizing the issuance of the bonds. Subject to the provisions of any resolution or trust indenture authorizing the issuance of bonds any moneys in any such sinking fund in excess of an amount equal to one year's interest on the bonds then outstanding secured by such sinking fund may be applied to the purchase or redemption of bonds. All such bonds so redeemed or purchased shall forthwith be cancelled and shall not again be issued. No person shall be permitted to use any toll highway without paying the toll established under this Section except when on official Toll Highway Authority business which includes police and other emergency vehicles. However, any law enforcement agency vehicle, fire department vehicle, public or private ambulance service vehicle engaged in the performance of an emergency service or duty that necessitates the use of the toll highway system, or other emergency vehicle that is plainly marked shall not be required to pay a toll to use a toll highway. A law enforcement, fire protection, or emergency services officer driving a law enforcement, fire protection, emergency services agency vehicle, or public or private ambulance service vehicle engaging in the performance of emergency services or duties that is not plainly marked must present an Official Permit Card which the law enforcement, fire protection, or emergency services officer receives from his or her law enforcement, fire protection, emergency services agency, or public or private ambulance service in order to use a toll highway without paying the toll. A law enforcement, fire protection, emergency services agency, or public or private ambulance service engaging in the performance of emergency services or duties must apply to the Authority to receive a permit, and the Authority shall adopt rules for the issuance of a permit, that allows public or private ambulance service vehicles engaged in the performance of emergency services or duties that necessitate the use of the toll highway system and all law enforcement, fire protection, or emergency services agency vehicles of the law enforcement, fire protection, or emergency services agency to use any toll highway without paying the toll established under this Section. The Authority shall maintain in its office a list of all persons that are authorized to use any toll highway without charge when on official business of the Authority and such list shall be open to the public for inspection. In recognition of the unique role of public transportation in providing effective transportation in the Authority's service region, and to give effect to the exemption set forth in subsection (b) of Section 2.06 of the Regional Transportation Authority Act, the following vehicles may use any toll highway without paying the toll: (1) a vehicle owned or operated by the Suburban Bus Division of the Regional Transportation Authority that is being used to transport passengers for hire; and (2) any revenue vehicle that is owned or operated by a Mass Transit District created under Section 3 of the Local Mass Transit District Act and running regular scheduled service.
Among other matters, this amendatory Act of 1990 is intended to clarify and confirm the prior intent of the General Assembly to allow toll revenues from the toll highway system to be used to pay a portion of the cost of the construction of the North-South Toll Highway authorized by Senate Joint Resolution 122 of the 83rd General Assembly in 1984.
605 ILCS 10/19