SPRINGFIELD, IL —An Illinois law banning guns within 1,000 feet of public parks violates a right under the Second Amendment to carry a weapon outside the home for self-defense, the state Supreme Court concluded in a unanimous decision issued on Thursday.

The 7-0 ruling came in the criminal case of Julio Chairez, who had appealed his 2013 conviction for having a gun near Aurora's Virgil Gilman Trail park, just west of Chicago. In addition to striking the law, Thursday's ruling also vacated Chairez's conviction. The 25-page opinion, penned by Chief Justice Lloyd Karmeier, says the law — in its scope — functions as "a categorical prohibition without providing an exception for law-abiding individuals." He adds: "It is therefore a severe burden on the recognized second amendment right of self-defense."

Thursday's ruling is in line with other rulings over recent years by the state's high court and the Chicago-based 7th U.S. Court of Appeals that found Illinois bans on citizens from carrying guns outside the home were unconstitutional. Such rulings have forced Illinois lawmakers who back tougher gun control laws to rethink their approach. The Illinois attorney general's office, whose lawyers defended the law, said Thursday it is reviewing the ruling and didn't have an immediately comment. It could appeal to the U.S. Supreme Court, which Karmeier said hasn't specifically addressed the issue of gun-free zones around public parks.

In his ruling, Karmeier says there are too many scenarios under the park law in which "innocent behavior could swiftly be transformed into" crimes. People living by parks could be charged simply by walking from their houses to their cars carrying a legal gun. To avoid breaking the law, he says, they would have to disassemble their guns each time they leave home, then reassemble them after driving far enough away.

"This requirement...renders the ability to defend oneself inoperable and is in direct contradiction to this court's (earlier) decisions..., which recognized that the right to carry firearms for self-defense may be especially important when traveling outside of the home," the ruling said.

The executive director of the Illinois State Rifle Association, Richard A. Pearson, welcomed Thursday's ruling.

"If you make all these 1000-foot restrictive zones, then chain them together, there's no place you can go with a firearm," he said. "They're always unconstitutional."

Karmeier, in his ruling, made a similar point. "The most troubling aspect" of the law, he wrote, "is the lack of any notification where the 1000-foot restriction zone starts and where it would end." That, he said, would make it especially hard for law-abiding gun owners to negotiate Chicago, which has over 600 city parks, putting them in constant peril of breaking the law.