The US Supreme Court on Monday extended the constitutional protection of the Second Amendment’s right to keep and bear arms to every jurisdiction in the nation.

The action places in serious doubt the constitutionality of a handgun ban in Chicago, and sets the stage for more legal challenges to an array of tough gun-control laws across the United States.

The 5-to-4 decision means that in addition to the federal government, state and local governments must comply with the high court’s 2008 landmark ruling recognizing an individual right to possess handguns in the home for self defense.

IN PICTURES: The debate over gun rights

Two years ago, in a decision called District of Columbia v. Heller, the high court struck down a handgun ban in Washington, D.C., ruling that it violated the right of individuals to keep and bear arms.

Because the District of Columbia is a federal enclave – rather than part of a state – the question remained open whether the newly articulated Second Amendment right would apply beyond federal jurisdictions like Washington, D.C., to states and municipalities.

That was the issue in Monday’s case, McDonald v. City of Chicago. Chicago maintains a handgun ban similar to the ban struck down in Washington. But it wasn’t clear from prior Supreme Court precedent whether Second Amendment protections extended to cities and states.

The high court has now made clear that they do.

“We have previously held that most of the provisions of the Bill of Rights apply with full force to both the federal government and the states. Applying the standard that is well established in our case law, we hold that the Second Amendment right is fully applicable to the states,” wrote Justice Samuel Alito for the majority.

A 'fundamental' right

The majority justices said the right to keep a handgun for self-protection in the home is a “fundamental” right, deeply rooted in America’s history and tradition.

Justice Alito quoted England's Sir William Blackstone as asserting that the right to keep and bear arms was “one of the fundamental rights of Englishmen.” He said the American colonists shared that view and decided to protect it.

“The right to keep and bear arms was considered no less fundamental by those who drafted and ratified the Bill of Rights,” Alito said.

In a dissent, Justice John Paul Stevens said the majority opinion overturned more than a century of Supreme Court precedent. “Although the court’s decision in this case might be seen as a mere adjunct to its decision in Heller, the consequences could prove far more destructive – quite literally – to our nation’s communities and to our constitutional structure,” he said.

“Today’s ruling marks a dramatic change in our law,” he said. “I would proceed more cautiously.”

Chicago's handgun ban on tenuous ground

The decision sends the case back to the Seventh US Circuit Court of Appeals in Chicago to reconsider the constitutionality of that city’s handgun ban. In effect, the appeals court judges must apply the same test the high court used to invalidate Washington, D.C.’s handgun ban.

Most legal analysts expect Chicago’s ban to be struck down.

The next major issue will be what legal standard lower court judges should apply when assessing whether a particular gun-control measure violates the Second Amendment.

A plurality of justices offered some guidance. “It is important to keep in mind that Heller, while striking down a law that prohibited the possession of handguns in the home, recognized that the right to keep and bear arms is not a right to keep and carry any weapon whatsoever in any manner whatsoever and for whatever purpose,” Alito wrote.

“We made it clear in Heller that our holding did not cast doubt on such longstanding regulatory measures as ‘prohibitions on the possession of firearms by felons and the mentally ill,’ ‘laws forbidding the carrying of firearms in sensitive places such as schools and government buildings, or laws imposing conditions and qualifications on the commercial sale of arms,’ ” he said.

“We repeat those assurances here,” Alito said. “Despite municipal respondents’ doomsday proclamations, incorporation does not imperil every law regulating firearms.”

'Due process' is basis of majority decision

In extending the Second Amendment to cities and states, the justices declined an invitation by gun rights lawyers to overrule prior legal precedents dating to 1873, 1876, and 1886.

Lawyers for the Second Amendment Foundation had asked the justices to consider relying on the privileges and immunities clause of the 14th Amendment. But that part of the high court’s jurisprudence has remained largely dormant since the 1800s and would have required the court to announce a major shift in the law.

Only one justice, Clarence Thomas, embraced this approach. Nonetheless, Justice Thomas joined the majority in most of its decision and concurred in the result.

Alito’s majority decision relied on the due process clause of the 14th Amendment, the provision most often cited by the Supreme Court when the high court has moved to enforce the protections in the Bill of Rights to the states.

The Bill of Rights was written and adopted as a check on the power of the national government. It was only later that the Supreme Court began enforcing those same rights against state and local governments. For example, state and local governments must respect free speech rights guaranteed in the Constitution, and state and local police must adhere to the privacy protections of the Fourth Amendment.

But the Supreme Court has not applied all of the rights in the Bill of Rights to the states. Some state courts do not recognize a right to a grand jury indictment or a jury trial in certain civil cases. Yet both of those rights are guaranteed in federal court by the Constitution.

On Monday, the high court extended its holdings in this area to declare that the Second Amendment must now be enforced at the state and local levels.

“In Heller we held that the Second Amendment protects the right to possess a handgun in the home for the purpose of self-defense,” Alito said. “A provision of the Bill of Rights that protects a right that is fundamental from an American perspective applies equally to the federal government and the states.”

Alito was joined in the majority opinon by Chief Justice John Roberts and Justices Antonin Scalia, Anthony Kennedy, and Clarence Thomas.

In addition to Stevens, Justice Stephen Breyer wrote a dissent that was joined by Justices Ruth Bader Ginsburg and Sonia Sotomayor.

“The Framers did not write the Second Amendment in order to protect a private right of armed self-defense,” Breyer wrote. “There has been, and is, no consensus that the right is, or was, fundamental,” he said. “No broader constitutional interest or principle supports legal treatment of that right as fundamental. To the contrary, broader constitutional concerns of an institutional nature argue strongly against that treatment.”

IN PICTURES: The debate over gun rights

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