A man accused in the deadly Tucson shooting rampage reportedly researched lethal injections, solitary confinement and political assassinations in the days before the attack.
A source close to the investigation into 22-year-old Jared Loughner told The Washington Post that a review of his computers turned up the internet searches.
Officials with the FBI and Justice Department declined to comment on the Post’s story.
Loughner’s alleged actions could help prosecutors as they begin the process of pursuing charges that could lead to the federal death penalty.
He was indicted last week on federal charges of trying to assassinate Arizona congresswoman Gabrielle Giffords and trying to kill two of her aides.
The January 8 shootings left six dead and 13 wounded including Ms Giffords.
Loughner has pleaded not guilty.