Like most legal jargon, the language in this statute is somewhat vague. It does appear however, that the statute is referring to the 'Regulation' of 'Unmanned Aircraft Systems', and I take this to mean things like the weight, speed, radio capabilities, and general operation of UAV's versus prohibiting them from being operated from certain areas.
Subsection C: Nothing in this Section shall infringe or impede any current right or remedy available under existing State law.
I take Subsection C to be an allowance on the part of local governing authorities to take action based on existing State laws including Illinois' versions of Disorderly Conduct, Breach of Peace, Reckless Endangerment and most importantly,
Trespass. This would then imply that local governing authorities could restrict the mere operation of UAV's from certain areas via clearly posted signage. What they could not do, is allow operation while at the same time restricting, say, the weight and/or size of the UAV, or maybe the radio frequency used by the operator to communicate with the UAV.
That's how I read it anyway. Also, here is a link to a Legal Brief that I found, and his opinion seems to be the same.
Effective immediately, the Illinois General Assembly has pre-empted all Illinois municipalities other than Chicago, including home rule municipalities…
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