The justices' 6-3 decision is expected to ultimately allow more people to legally carry guns on the streets of the nation's largest cities - including New York, Los Angeles and Boston - and elsewhere. About a quarter of the U.S. population lives in states expected to be affected by the ruling, the high court's first major gun decision in more than a decade.
The ruling comes as Congress is actively working on gun legislation following recent mass shootings in Texas, New York and California. The Senate passed the bipartisan gun safety bill late into the night Thursday, with the House expected to take up the measure on Friday.
Justice Clarence Thomas wrote for the majority that the Constitution protects "an individual's right to carry a handgun for self-defense outside the home."
In their decision, the justices struck down a New York law requiring people to demonstrate a particular need for carrying a gun in order to get a license to carry one in public. The justices said the requirement violates the Second Amendment right to "keep and bear arms."
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California, Hawaii, Maryland, Massachusetts, New Jersey and Rhode Island all have similar laws likely to be challenged as a result of the ruling. The Biden administration had urged the justices to uphold New York's law.
Backers of New York's law had argued that striking it down would ultimately lead to more guns on the streets and higher rates of violent crime. The decision comes at a time when gun violence already on the rise during the coronavirus pandemic has spiked anew.
Reaction to the ruling in New York Thursday morning was swift.
New York Governor Kathy Hochul said the Supreme Court has "stripped away the rights" of New York with a decision "frightful in its scope," setting us back "to the days of our founding fathers."
"The language we are reading is shocking," Hochul said.
Hochul noted the decision came down at the exact moment she planned to sign Alyssa's Law, which requires New York school districts to consider installing silent panic alarms and other direct links to law enforcement agencies.
She said now people with guns can enter supermarkets, like in Buffalo, where 13 people were shot.
"This could place millions of New Yorkers in harm's way," Hochul said. "This decision is not just reckless, it's reprehensible. It is not what New Yorkers want."
New York City Mayor Eric Adams said an emergency meeting will be held by leaders of all major cities to come up with 'formidable way' to protect innocent citizens from being hurt by gun violence. Something experts say could increase with the uptick in firearm sales.
Watch: Mayor Eric Adams reacts to SCOTUS conceal carry decision
New York City Council members immediately announced plans for new, updated gun legislation.
"The Supreme Court's decision to overturn New York's gun laws is dangerous and puts New Yorkers at risk," said Council Speaker Adrienne Adams. "Our country and city are already facing a gun violence crisis, and this ruling only threatens to worsen the harm inflicted on our communities. The Council is prepared to take action to protect New Yorkers from the adverse public safety effects of this Supreme Court ruling."
Adams held a news conference Thursday afternoon.
In most of the country gun owners have little difficulty legally carrying their weapons in public.
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But that had been harder to do in New York and the handful of states with similar laws. New York's law, which has been in place since 1913, says that to carry a concealed handgun in public, a person applying for a license has to show "proper cause," a specific need to carry the weapon.
The state issues unrestricted licenses where a person can carry their gun anywhere and restricted licenses that allow a person to carry the weapon but just for specific purposes such as hunting and target shooting or to and from their place of business.
The Supreme Court last issued a major gun decision in 2010. In that decision and a ruling from 2008 the justices established a nationwide right to keep a gun at home for self-defense. The question for the court this time was about carrying one outside the home.
The Associated Press contributed to this report.
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