Law enforcement sources tell the Washington Post that a computer seized from Loughner’s home shows that he was researching the consequences to an assassination.
Prosecutors will likely use such evidence to try to prove that Loughner was not insane at the time of the shooting and can stand trial. They are expected to also use notes found in Loughner’s home, which say, among other things, “I planned ahead.”
He has been charged in federal court with the attempted murder of Giffords and two of her aides. He has pleaded not guilty.
Prosecutors say they will bring other charges, including the murder of another Giffords aide and a federal judge, against Loughner, and the state is likely to bring separate charges for the murders and attempted murders of those not working for the federal government.
Loughner is accused of shooting 19 people the morning of Jan. 8. Six of those people died. Giffords, who was shot in the head, is recovering at a Houston rehabilitation center.