Back here at home investigators are poring other that notebook believed to be that of james home. The accused gunman in the movie theater shooting. Abc's dan harris tells us, experts tell us that they... See More
Back here at home investigators are poring other that notebook believed to be that of james home. The accused gunman in the movie theater shooting. Abc's dan harris tells us, experts tell us that they are tauchb hallmark of mass murders. Reporter: Tonight law enforcement officials are analyzing the notebook believed to be from the suspect james holmes. Discovered in the mailroom at the university of colorado where holmes was a student. When investigators first found the package they were so concerned it too would be rigged with explosives, they sent in a robot to handle it. Inside the notebook they reportedly found plans for a massacre including drawings of a stick figure gunman mowing down his victims. Universally, mass shooters is all about revenge. He wanted to pay society back for what he believed society had done to him. And I think the note book will talk about that. Reporter: In america's over-crowded history of mass murder nearly every perpetrator has left behind documentation. The columbine killers left voluminous diaries, diagrams of the school, and ominous videos. Jared lee loughner, who shot gab reel giffords, posted incomprehensible videos about his community college. This is my genocideool. Reporter: And seoung hi cho of virginia tech recorded a garbled rant at unnamed and perhaps unknowable wrong-doers. I dike like jesus christ to inspire for the weak and defenseless people. I think some of this is that these attackers want to be understood and at the time they carry out the attack they don't feel understood, like they have no other options. It may be driving this. Reporter: But given the confused ramblings of his predecessors, fechb he decides to reveal his motive, james holmes, the rest of us will find it either incomprehensible, of or unacceptable. We want to update you on one of the victims of shoots. Caleb medley, on tuesday, his wife katie, also in the theater gave bifrt to a healthy baby boy named hugo. We are pleased to report, caleb now has sensation on the left side of his body. And when baby hugo was brought to his room, dad's heart rate went through the roof.
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