The theoretical and empirical evidence (which overall is inconclusive) is consistent with concluding that a right to carry firearms in public may promote self-defense. – Judge Richard Posner

CHICAGO — In a big victory for gun rights advocates, a federal appeals court on Tuesday struck down a ban on carrying concealed weapons in Illinois — the only state where it had remained entirely illegal.

The 7th U.S. Circuit Court of Appeals said state lawmakers have 180 days to write a new law that legalizes concealed carry.

Gun rights advocates long have argued that the prohibition against concealed weapons violates the U.S. Constitution's Second Amendment and what they see as Americans' right to carry guns for self-defense. The court majority on Monday agreed, reversing lower court rulings against a lawsuit that had challenged the state law.

"The Supreme Court has decided that the amendment confers a right to bear arms for self-defense, which is as important outside the home as inside," Judge Richard Posner wrote in the court's majority opinion. "The theoretical and empirical evidence (which overall is inconclusive) is consistent with concluding that a right to carry firearms in public may promote self-defense."

He continued: "Illinois had to provide us with more than merely a rational basis for believing that its uniquely sweeping ban is justified by an increase in public safety. It has failed to meet this burden."

The court ordered its ruling stayed "to allow the Illinois legislature to craft a new gun law that will impose reasonable limitations, consistent with the public safety and the Second Amendment as interpreted in this opinion, on the carrying of guns in public," Posner said.

Attorney General Lisa Madigan's office, which is responsible for defending the state's laws, said it was reviewing the ruling and would comment later Tuesday.

Also studying the opinion were aides to Gov. Pat Quinn, favors strict gun control laws and proposed an assault weapons ban earlier this year that lawmakers defeated. Quinn has vowed to again bring legislation that would prohibit the sale or possession of semi-automatic rifles and other guns.

The leader of the Illinois State Rifle Association, Richard Pearson, praised the federal court's decision and said the state could have a new concealed carry law by early next month. A bill has already been written by Rep. Brandon Phelps of Harrisburg that includes provisions for background checks, field provisions and other issues, Pearson said.

"We are extremely pleased with the ruling," Pearson said. "Now that the court has ruled ... we will work as soon as possible with legislators to craft a concealed carry bill for the state of Illinois."

He said lawmakers could consider it and pass it during a weeklong legislative session in January if they wanted to.

"Christmas came early for law-abiding gun owners," said Phelps, whose proposed legislation came within three votes of passing in 2011.

"I said on the floor, 'A lot of people who voted against this, one of these days, you're going to wish you did, because of all the limitations and the safety precautions we put in this bill, because one of these days, the court's going to rule and you're not going to like the ruling.' Today's the day."

"The court's pretty much said there's no restrictions," Phelps said.

The ruling stems from a lawsuit filed by former corrections officer Michael Moore of Champaign, farmer Charles Hooks of Percy in southeastern Illinois and the Bellevue, Wash.-based Second Amendment Foundation.