430 ILCS 70/5

Notice of assemblage in writing-Contents. It is unlawful for any group or organization to conduct or participate in any march, assembly, meeting, parade, or gathering on roadways unless the principal law enforcement officer has been given notice in writing of the location, the maximum number of persons participating, and the names and addresses of the organizers of the march, assembly, meeting, parade, or gathering, its route, and its time of inception and duration at least 24 hours before inception.