220 ILCS 5/4-301
The Commission may confer in person, or by correspondence, by attending conventions, or in any other way, with Commissions and any and all agencies dealing with public utilities of other states and of the United States on any matters relating to public utilities.
The Commission shall have full power and authority to make joint investigations, hold joint hearings within or without the State, and issue joint or concurrent orders in conjunction with any official, board, commission or agency of any state or of the United States. In the holding of such investigations or hearings, or in the making of such orders, the Commission shall function under agreements or compacts between states or under the concurrent power of states to regulate the interstate commerce, or as an agency of the United States, or otherwise.
The Commission shall make whenever requested by the Governor, the General Assembly, or either branch of the General Assembly a report within 90 days or any other time period specified within such request, which shall contain copies of all orders issued by the Commission which it deems of special importance or general significance, and any information in the possession of the Commission which it shall deem of value to the people of the State.
The Commission shall conduct a hearing and take testimony relative to any pending legislation with respect to any person, corporation or matter within its jurisdiction, if requested to do so by the Governor, the General Assembly, or either branch of the General Assembly , and shall report its conclusions to the Governor or the General Assembly, as the case may be. The Commission may also recommend the enactment of such legislation with respect to any matter within its jurisdiction as it deems wise or necessary in the public interest. The Commission shall, at such times as the Governor, the General Assembly, or either branch of the General Assembly shall direct, examine any particular subject connected with the condition and management of public utilities, and report to the Governor or the General Assembly, as the case may be, in writing its opinion thereon with its reasons therefor.
220 ILCS 5/4-301