At the trial this week of Raulie Casteel, the Michigan man accused of going on a shooting spree in October 2012, Casteel's lawyer explained that his client shot at nearly two dozen people because of his conspiracy beliefs.
"Casteel thought drivers along Michigan's Interstate 96 were part of a government conspiracy against him," he said in court Monday, according to ABC News. So he started firing.
Casteel, a husband and father, is taking the stand in his own trial, which continues Tuesday.
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"To my way of thinking at the time, [the shooting] was to get rid of the demons so to speak. It was those thoughts - the fear, the anxiety," the confessed shooter said Monday.
After being fired from his job as a scientist, Casteel says he believed his phone calls were being monitored and that government helicopters were watching him.
Casteel is only one of many violent conspiracy theorists who have taken up arms and attacked innocent victims.
In 2002, Luke Helder, a Minnesota college student, left 18 pipe bombs left in mailboxes that injured six people in Iowa, Illinois, Nebraska, Colorado and Texas. Before the bombings Helder wrote a six-page letter to a university student newspaper discussing his belief in various conspiracy theories. Helder wrote that each person can create his or her own reality, and that "once you begin to realize the potential you have as a consciousness/soul/spirit, you will begin to harness the abilities you have to produce realities."