235 ILCS 5/7-7
Any five residents of the city, village or county shall have the right to file a complaint with the local commission stating that any retailer licensee, subject to the jurisdiction of the local commission, has been or is violating the provisions of this Act or the rules or regulations issued pursuant hereto. Such complaint shall be in writing in the form prescribed by the local commission and shall be signed and sworn to by the parties complaining. The complaint shall state the particular provision, rule or regulation believed to have been violated and the facts in detail upon which belief is based. If the local commission is satisfied that the complaint substantially charges a violation and that from the facts alleged there is reasonable cause for such belief, it shall set the matter for hearing and shall serve notice upon the licensee of the time and place of such hearing and of the particular charge in the complaint.
235 ILCS 5/7-7