65 ILCS 5/10-1-43
The electors of any municipality may adopt and become entitled to the benefits of this Division 1 in the following manner: Whenever 1,000 of the legal voters of such municipality, voting at the last preceding election petition the circuit court for the county in which the municipality is located to order submitted to a vote of the electors of such municipality the proposition as to whether such municipality and the electors thereof shall adopt and become entitled to the benefits of this Division 1, the circuit court shall order such proposition certified and submitted accordingly at the next succeeding election in accordance with the general election law, and if such proposition is not adopted at such election the same shall in like manner be ordered to a vote of the electors of such municipality by the circuit court upon like application at any election thereafter, and an order shall be entered of record in the circuit court for the submission of such proposition as aforesaid. The clerk of the circuit court shall certify the proposition for submission.
If the required number of 1,000 electors exceeds a number equal to 1/8 of the legal voters of any such municipality voting at the last preceding municipal election, then such petition or application need not be signed or made by more than 1/8 of the legal voters of such municipality voting at the last preceding municipal election.
If this Division 1 is adopted by a municipality that before adoption was subject to the provisions of Division 2.1 of this Article 10, the provisions of this Division 1 shall apply except as to the board of fire and police commissioners and firemen and policemen. The provisions of Division 2.1 shall continue to apply to the board of fire and police commissioners and firemen and policemen.
A municipality that has adopted this Division 1 may abolish it in the same manner prescribed for its adoption.
65 ILCS 5/10-1-43