And it has nothing to do with the Tea Party or Sarah Palin at all.
Should you be so inclined, the rest of the story is here:
Obligatory: Video in Which Tucson Killer Jabbers About ‘Illegal Wars’ Like Your Average DKos Diarist or Cindy Sheehan
How to Talk to a Follower of the Zeitgeist Cult (If You Must)
Zeitgeist: Watch the Conspiracy Movie That Had a ‘Profound Impact’ on Tucson Mass Murder Suspect Jared Loughner
Salvia, Zeitgeist and the Tucson Shooter
‘Vain in Their Imaginations’: God-Haters and the Tucson Massacre
*This movie reportedly had a profound impact on him. That in and of itself wouldn't do that but the movie with copious amounts of pot consumption, hating religion and an unhealthy obsession with a female politician could.