Peter Lefferts is a lawyer and former soldier. During an incident overseas, he accidentally killed squad mate Charlie Kent after Kent accidentally killed a Muslim family, an incident that was covered up. The truth was eventually discovered by the Jeffersonian Institute and Agent Seeley Booth of the FBI. A former soldier himself with combat experience, Booth recognized that neither Lefferts or Kent intended to kill anyone and Lefferts killing Kent was done on instinct when Lefferts entered after all the gunfire, Kent spun towards him and Lefferts fired, thinking Kent was an enemy combatant. Unable to live any longer with the guilt, Lefferts hanged himself and left a suicide note apologising for killing Kent.