from the Secret Service report: bullying and "targeted school shootings"

Key Finding 7

Many attackers felt bullied, persecuted, or injured by others prior to the attack.

Implications

Bullying was not a factor in every case, and clearly not every child who is bullied in school will pose a risk for targeted violence in school. Nevertheless, in a number of the incidents of targeted school violence studied, attackers described being bullied in terms that suggested that these experiences approached torment. These attackerstold of behaviors that, if they occurred in the workplace, likely would meet legal definitions of harassment and/or assault.

The Final Report and Findings of the Safe Schools Initiative

I'm thinking that this must have been the section of the report that got all the headlines when it was released 12 years ago. I remember a huge amount of attention paid to bullying in the wake of Columbine.