Shortly after the Boston bombing, a disconcerting and seemingly conspiratorial story came out: chief suspect Tamerlan Tsarnaev, who had been killed in a shootout with police, was alleged to be linked to an unsolved triple homicide that occurred nearly two years earlier. But the story actually wasnt so conspiratorial. The FBI began investigating, and a month later a man linked to both Tsarnaev and the killings, Ibragim Todashev, was reportedly shot and killed in his apartment by the bureau. …