Bullying is portrayed as the main cause for Peter Houghton’s mass shooting at Sterling High. Peter has endured a lifetime of bullying, from the first day of kindergarten to the days before he shot and killed his bullies in high school. Peter isn’t the only student to be bullied, but the narrative shows how some people are more susceptible to the effects of high school taunts. In one telling scene, Jorden McAfee, Peter’s defense lawyer, is told by a colleague that nearly everyone has a traumatic event from high school. Most people block these events out because of how damaging they are to the psyche. Others, however, cannot block them out. These people turn into victims like Peter, who buckle under the pressure of bullying. Peter’s response is to push back, which results in the deaths of his bullies.

Bullying is seen by many as a de-facto experience in high school. Others look at bullying as a right-of passage. For the jocks and popular kids at Sterling High, bullying is one way to establish themselves among the high school’s hierarchy. They are on top, and their actions show everyone that they are in fact the “coolest” kids, the ones who determine the pecking order.