Selective mutism, a component of the severe social anxiety disorder that Cho was diagnosed with in eighth grade, is not associated per se with violent personalities, but may be a source of ridicule by others, and may prompt bullying. A history of being taunted and bullied in school often underlies deadly incidents such as the Columbine High School killings in 1999, authorities on violent behavior in adolescents say.
Although there are no confirmed reports of Cho being a target, "it would be reasonable?to assume that Cho was a victim of some bullying, though to what extent and how much above the norm is not known," the panelists wrote.
That Cho thought of himself as a victim was made clear by a videotaped rant that he mailed to NBC News in the two hours between murders at the West Ambler Johnson dormitory and a killing spree in Norris Hall.
"You had a hundred billion chances and ways to have avoided today, but you decided to spill my blood," Cho told the camera in an almost robotic monotone. "You forced me into a corner and gave me only one option. The decision was yours. Now you have blood on you hands that will never wash off."
