220 ILCS 5/14-107
Except as otherwise provided in this Article the transit commission shall have general supervision of the corporations owning or operating the comprehensive unified local transportation system or any of the other local transportation facilities mentioned in the foregoing Section 14-105. It shall inquire into and keep itself informed as to the general condition of such corporations their franchises, capitalization, rates and charges, the manner in which their properties are managed and operated with respect to adequacy of service, and as to compliance with the applicable provisions of this Act, with the orders of the transit commission, and with the requirements, terms, and conditions of any ordinance grant, permit or franchise.
The corporations subject to the jurisdiction of the transit commission shall furnish to the commission all information required by it to carry into effect the provisions of this Article.
Whenever required by the transit commission such corporations shall deliver to the commission all maps, profiles, reports, documents, books, accounts, papers and records in their possession in any way relating to their property or affecting their business, and inventories of their property, in such form as the commission may direct, or verified copies of all or any of the same.
220 ILCS 5/14-107