For people who have long suspected that there is some link between violent video games and real-world violence, the statement offered frightening new evidence for why the video-game industry should be more strictly regulated.  Many gamers and columnists, however, rolled their eyes and collectively muttered "here we go again."  "How many times are we going to do this?" Paul Tassi wrote in a Forbes story, "The idiocy of blaming video games for the Norway massacre." "Really now, it's getting absurd."  "Norway Killer Played World of Warcraft, Which Probably Means Nothing At All," declared a headline on Time.com, which shares a parent company with CNN.  Whether shoot-'em-up video games can incite violence has been a long-running debate among the public as well as in clinical psychology. This type of discussion tends to come up every time it's revealed that a high-profile killer also played video games.  Perhaps the most memorable case study was the Columbine High School shooting in Colorado in 1999, during which experts speculated about the influence of the game "Doom" on the teenagers who carried out that crime.  And for years, the controversial "Grand Theft Auto" series, in which players can kill police officers, was targeted by critics who said it glamorizes criminals and promotes violence. The makers of the game were even sued by the attorney for a convicted cop killer in Alabama, who argued the game inspired his client.  Ultimately, it seems like science should judge whether playing violent video games can lead to a propensity for violence in the real world. A number of recent studies have cast doubts about the link between video games and violence, but there's no definitive answer.
Norway's alleged mass killer testified on Thursday that he played video games as a way to train for a shooting spree that killed 77 people last summer. In particular, Anders Behring Breivik said at...