On Thanksgiving night, a shooter opened fire at the Riverchase Galleria mall in Hoover, Ala. Police killed one man.

But as has become increasingly clear, Emantic “E.J.” Bradford Jr. was one of the good guys.

The military veteran and legal gun carrier from Hueytown, Ala., was likely killed while trying to protect his fellow citizens, according to eyewitness reports. And for that, his family says, he died ignominiously. Police arrested the alleged shooter Thursday.

The Thanksgiving tragedy in Hoover, Ala., highlights an American problem: The deaths of black men, legally armed and who have committed no crime, at the hands of police. At a time when the president and guns rights activists have suggested that “good guys with guns” are a solution for stopping mass shooters, some black gun owners are wondering if “helping while black” is too dangerous....

The killing of Mr. Bradford is not a stand-alone example. Three days before his death, a young man named Jemel Roberson was buried in Illinois. An aspiring police officer and legal gun-carrier, Mr. Roberson singlehandedly apprehended a mass shooter at Manny’s Blue Room bar in Robbins, where Roberson worked as a security guard. A Midlothian police officer responded, and shot and killed Roberson. In June, Navy veteran Jason Washington was shot and killed by Portland State University police in Oregon, after reportedly trying to stop a fight outside a bar. Witnesses say Washington was trying to de-escalate the situation, including confiscating his friend’s gun. He had a pistol permit. A grand jury declined to indict the two officers involved....

For one black gun owner, the shootings reinforce the broader struggle for police – and Americans more broadly – to address biases that become heightened when guns are drawn.

“There are 16 million concealed carry permit holders around the nation and less than two decades ago there were a minuscule amount, and the training has not caught up from the law enforcement side or the civilian side,” says Maj Toure, a Philadelphia hip-hop artist and founder of Black Guns Matter. “Meanwhile, the television has told you that the white dude with the AR-15 is supposed to have it. When you see a black guy with a gun, the ‘good guy with a gun’ goes out the window. There is conditioning involved, and we have to break that stigma.”