The Justice Department opened an investigation this week into the killing of Trayvon Martin, a 17-year-old high school student who was shot dead on Feb. 26 in Sanford, Florida.

Martin was returning to the home of his father’s girlfriend from a 7-Eleven, armed with a package of Skittles and an iced tea, when he was killed. George Zimmerman -- a self-appointed neighborhood watch captain, according to news reports -- had called 911 and proceeded to follow Martin, even after the dispatcher advised him not to. Soon after, Zimmerman told police, he shot Martin.

Crime is a problem in the U.S. So are guns. According to the local police chief, Zimmerman, 28, had a permit for a concealed weapon, which is easily obtained in Florida. He also had a penchant for calling the police, having made 46 such calls in the past 13 months to report suspicious behavior. Based on news reports, it appears that Zimmerman believed he had much to fear from crime. As things turned out, Martin had much more to fear from Zimmerman’s gun.

Martin didn’t have a lot of protection from the law, either. Florida’s “Stand your Ground” law allows people to use deadly force -- even before an unarmed person -- provided they “reasonably believe” it’s necessary to defend themselves. It’s a shockingly low standard, but it’s not inconsistent with the highest law of the land.

Scalia’s Opinion

Writing for a bitterly divided Supreme Court in 2008, Justice Antonin Scalia brushed past the ambiguous language of the Second Amendment and the convoluted history of gun rights in the U.S. to establish or affirm (depending on your point of view) a right of individuals to own guns. Yet in his 5-4 opinion in District of Columbia v. Heller, even Scalia maintained that the right is not unlimited. “We do not read the Second Amendment to protect the right of citizens to carry arms for any sort of confrontation,” Scalia wrote.

The question, then, is what public policies are constitutionally justified to prevent the wrong “sort of confrontation”?

At present, it seems, not many. Since the Heller decision, which overturned Washington’s strict gun law, controls have been crumbling across the nation. In Oklahoma, lawmakers appear poised to enact an “open carry” law, allowing residents to display firearms in public. The National Rifle Association and other lobbyists for gun manufacturers are pushing for loaded guns to be allowed in college classrooms and dormitories. Legislation proposed in Congress would force states to allow holders of concealed weapons permits from other jurisdictions to carry guns where it’s otherwise illegal.

Dissolution of Order

A ruling this month in Maryland seems emblematic of the dissolution of order. U.S. District Judge Benson Everett Legg overturned a state law requiring that residents show a “good and substantial reason” to carry a gun on the grounds that such a standard was unconstitutional.

Activists are now insisting that race played a role in Martin’s death. Perhaps it did. (In a recording of Zimmerman’s 911 call, it sounds as if Zimmerman mutters a racial epithet.) On Tuesday, the state attorney’s office for Brevard and Seminole counties announced that a grand jury would investigate the shooting.

A racial motivation would push the case toward criminal terrain, and justly so. But racism is not the only way a mind can be distorted and its judgment impaired. There is nothing in Florida law, for example, to prevent people whose perceptions are distorted by fear from owning a gun -- or an arsenal of them -- and carrying a concealed and loaded weapon on the street.

This is one obvious flaw in the mad rush to arm America, which we hope statehouses, courts and Congress will belatedly factor into their thinking. Guns ever at the ready will be used, with tragic results.

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