50 ILCS 105/2
No alderperson of any city, or member of the board of trustees of any village, during the term of office for which he or she is elected, may accept, be appointed to, or hold any office by the appointment of the mayor or president of the board of trustees, unless the alderperson or board member is granted a leave of absence from such office, or unless he or she first resigns from the office of alderperson or member of the board of trustees, or unless the holding of another office is authorized by law. The alderperson or board member may, however, serve as a volunteer fireman and receive compensation for that service. The alderperson may also serve as a commissioner of the Beardstown Regional Flood Prevention District board. Any appointment in violation of this Section is void. Nothing in this Act shall be construed to prohibit an elected municipal official from holding elected office in another unit of local government as long as there is no contractual relationship between the municipality and the other unit of local government. This amendatory Act of 1995 is declarative of existing law and is not a new enactment.
50 ILCS 105/2