No PCs enraged Columbine shooters: study

“Very soon thereafter—a couple of days—they started to plan the actual attack,” Block said. Block has published his research in the current issue of the American Journal of Forensic Psychiatry.

“Two-thirds of middle-school boys play M-rated games regularly,” said Cheryl Olson, co-director of the Center for Mental Health and Media at the Massachusetts General Hospital. M-rated games contain intense violence or sexual content. “They’re not turning kids into killing machines.”

Block sifted through thousands of pages of documents released by Columbine investigators and said he believes Harris’ and Klebold’s parents banned them from their computers after the two were caught breaking into an electrician’s van in 1998. Harris and Klebold previously had been temporarily kept off computers at school or home, and after each incident, Block said, the boys’ writings or behaviour became more violent.

Block said he worries about people immersing themselves so deeply into video games and online worlds. “How do you pull them out, without triggering homicidal or suicidal behaviour?” he asked.

Olson cautioned against over-generalising from Columbine records. After the Colorado massacre, the Secret Service searched for common threads in more than three dozen school shootings, she said. “The commonalities they found were male gender and being treated for depression or showing signs of depression,” Olson said.

Some of the shooters were good students, some bad; some were bullies, some were bullied; and some played video games, but most did not, she said.