It's a misconception that African Americans do not commit mass killings like the Navy yard shooting in Washington, D.C. While the number of black mass shooters is low, they do exist. Here's a list of seven black mass shooters.
Ferguson opened fire on a crowded Long Island Rail Road train in 1993, killing six people and injuring 19. In his pockets, police found scribbled notes in which Ferguson expressed his reasons for the shooting — including a previous arrest. At the trial, Ferguson's lawyers used the "black rage" defense, claiming that Ferguson had been driven to insanity because of racism and could not be held responsible for his crimes. Ferguson was sentenced to 315 years to life in prison.
Omar S. Thornton
In 2010 Thornton had been called in by his employer, Hartford Distributors in Connecticut, to be disciplined for stealing inventory. After signing a resignation agreement, Thornton opened fire, killing eight people before turning the gun on himself.
Shortly after being released from prison, Clemmons shot and killed four police officers in Parkland, Wash. Clemmons managed to evade police for two days before being shot and killed by officers in Seattle.
Dunlap shot and killed four people in an Aurora, Colo., Chuck E. Cheese's restaurant in 1993. Yes, the same city in which James Holmes opened fire in a crowded theater during a screening of Batman in 2012. Dunlap was sentenced to death, but Colorado's current governor, John Hickenlooper, delayed his sentence indefinitely in May 2013.
John Allen Muhammad
Muhammad, better known as the "D.C. sniper," was the mastermind of the 2003 Beltway sniper attacks. Over a period of three weeks, Muhammad and his protégé, Lee Boyd Malvo, killed 10 people. During the trial, prosecutors surmised that Muhammad had planned the killings in order to have a cover for the eventual murder of his ex-wife, Mildred. However, that theory was thrown out by the judge, who stated that no clear link had been established. Muhammad was executed on Nov. 20, 2009.
Lee Boyd Malvo
At 17 years of age, Lee served as John Allen Muhammad's accomplice during the D.C.-sniper killings. In his confession, Lee said that he and Muhammad planned to kill six white people in order to "terrorize the nation." Lee is serving six consecutive life sentences without a possibility of parole.
Dorner's killing spree shook the Los Angeles area for nearly a week. Over nine days in February 2013, Dorner killed four people, including three police officers, and left three injured. In his manifesto, posted online before the shootings, Dorner recounted the racism he encountered while working as a Los Angeles Police Department officer and the firing that he deemed unfair. Dorner died of a self-inflicted gunshot during a standoff with police.