The Illinois Supreme Court had already held that the Second Amendment protects a right to carry guns in most public places, and in today’s People v. Chairez it likewise rejected a ban focused on carrying within 1000 feet of parks:
The State argues that the conduct of possessing a firearm within 1000 feet of a public park is unprotected by the second amendment because the prohibition falls within Heller’s declaration that “laws forbidding the carrying of firearms in sensitive places such as schools and government buildings” do not violate the second amendment rights of those prosecuted under such laws….
Beyond Heller‘s two examples of “sensitive places,” i.e., “schools and government buildings,” the Supreme Court has not yet provided a list of additional sensitive places that fall outside the second amendment protection or given any guidance on the breadth of its statement…. We, however, need not address whether the 1000-foot firearm restriction falls outside of the ambit of the second amendment because we agree with the approach taken by other courts that assume some level of scrutiny must apply to Heller‘s “presumptively lawful” regulations….
[This] analysis begins with a balance of considerations where the quantity and persuasiveness of the State’s evidence required to justify the challenged restrictions varies depending on how much it affects the core second amendment right to armed self-defense and whose right it affects. The rigor of this means-end analysis “depends on ‘how close the law comes to the core of the Second Amendment right and the severity of the law’s burden on the right.'” The closer in proximity the restricted activity is to the core of the second amendment right and the more people affected by the restriction, the more rigorous the means-end review. If the State cannot proffer evidence establishing both the law’s strong public-interest justification and its close fit to this end, the law must be held unconstitutional….
by Eugene Volokh