Shortly after the high court Monday along ideological lines - with five conservative-moderate justices in favor of gun rights and four liberals opposed - Chicago Mayor Richard M. Daley said officials were already at work rewriting the city ordinance to adhere to the court ruling while protecting Chicago residents from gun violence.
"We will never give in to those who use guns to harm others," Daley said in comments aimed at his constituents. "Your fight is my fight and we're in this together."
And in other cities and states, officials said they were confident their gun control laws would withstand legal challenges.
"We do think it'll probably give us some bigger legal bills, but I suspect that we will be able to continue to do exactly what we've been doing - have reasonable regulations as to who can buy and where you can carry," New York City Mayor Michael Bloomberg, an ardent gun control advocate, said of Monday's ruling.
The decision didn't explicitly strike down nearly 30-year-old handgun bans in Chicago and its suburb of Oak Park. Instead, it ordered a federal appeals court to reconsider its ruling. But it left little doubt that the statutes eventually would fall.
In the majority decision, Justice Samuel Alito wrote that the Second Amendment right "applies equally to the federal government and the states."
But the decision also signaled that some limitations on the Constitution's "right to keep and bear arms" could survive legal challenges. Alito noted that while fully binding on states and cities, the Second Amendment "limits (but by no means eliminates) their ability to devise solutions to social problems that suit local needs and values."
Justices John Paul Stevens and Stephen Breyer, joined by Justices Ruth Bader Ginsburg and Sonia Sotomayor, each wrote a dissent. Stevens said that unlike a ruling two years ago overturning a Washington, D.C., handgun ban, Monday's decision "could prove far more destructive - quite literally - to our nation's communities and to our constitutional structure."
Gun rights supporters had challenged the Chicago and Oak Park laws - the last two remaining outright bans in the country, according to The Brady Center to Prevent Gun Violence - almost immediately after the high court struck down a ban on handguns and a trigger lock requirement for other guns in Washington, a federal city with a unique legal standing. That ruling applied only to federal laws.
Lower federal courts upheld the Illinois cities' bans, noting that judges on those benches were bound by Supreme Court precedent and that it would be up to the high court justices to ultimately rule on the true reach of the Second Amendment.
Monday's ruling was a victory for gun rights supporters, but they also said they expected state and local governments to draft laws to impede gun ownership.
Attorney David Sigale, who represented one of the plaintiffs associated with Monday's decision, said he has been advising prospective handgun owners to hold off buying them.
"In light of Mayor Daley's threat ... that there could be a whole new mess of regulations on the books, which I'm sure will only go to further hinder and burden the Constitutional rights given today, I think it would be prudent to wait and see what those developments are before everyone rushes out and avails themselves of this new right," Sigale said.
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Wayne LaPierre, executive vice president of the National Rifle Association, said he expects the same from other municipalities as well, saying the NRA "will continue to work at every level to insure that defiant city councils and cynical politicians do not transform this constitutional victory into a practical defeat through Byzantine regulations and restrictions."
In Massachusetts, Attorney General Martha Coakley said the ruling would not pose a problem because the state controls, but doesn't ban, guns. Massachusetts Gov. Deval Patrick is pushing a bill that would make it illegal to buy more than one gun per month.
"The provision in the governor's bill relative to a one-gun-a-month limit is not analogous since it does not ban the ownership of firearms, but just regulates the amount," said Patrick's spokesman, Kyle Sullivan.
Daley didn't specify what measures he intends to push, but he said he planned to move quickly to get them in front of the City Council, saying that it is possible a special session will be called to address the issue.
He said he's considering creating a registry of the names and addresses of everyone in the city who legally owns a handgun, which would be made available to police officers, firefighters and other "first responders" before they arrive at the scene of emergencies.
The mayor also said Chicago might follow the District of Columbia's lead in requiring prospective gun owners to take training courses that include several hours of classroom learning about gun safety and passing a 20-question test.
Daley has suggested that owners may be required to buy insurance for those guns.