The last few years' shootings by high school children have put a national spotlight on juvenile violence. After conducting more than 5,000 interviews with juvenile and adult offenders over almost 20 years of forensic psychology, Shawn Johnston, a forensic psychologist in San Rafael, California, offers this opinion:

The recent bunch of accused killers are "very self-centered, very self-absorbed, angry youngsters who derive extraordinary pleasure from savage vengeance they wreak on one another."

The mental world of these young killers is "all about 'me.' They're frustrated, angry, in some pain, not getting everything they want. They feel like victims. They have no concern about others—they don't think about others. It's all about who they are and what they want."