625 ILCS 5/11-612
Except as authorized in the Automated Traffic Control Systems in Highway Construction or Maintenance Zones Act and Section 11-208.8 of this Code, no photographic, video, or other imaging system may be used in this State to record vehicle speeds for the purpose of enforcing any law or ordinance regarding a maximum or minimum speed limit unless a law enforcement officer is present at the scene and witnesses the event. No State or local governmental entity, including a home rule county or municipality, may use such a system in a way that is prohibited by this Section. The regulation of the use of such systems is an exclusive power and function of the State. This Section is a denial and limitation of home rule powers and functions under subsection (h) of Section 6 of Article VII of the Illinois Constitution.
625 ILCS 5/11-612