Jared Lee Loughner has pleaded guilty to going on a rampage in Tucson, Ariz., that left six dead and wounded then-Congresswoman Gabrielle Giffords and 12 others.
Loughner's plea Tuesday allows him to avoid the death penalty in a mass shooting that gained worldwide attention in January 2011 because his intended target was the congresswoman. Among the dead were Arizona's chief federal judge and a Giffords' aide.
Federal Judge Larry A. Burns had found that Loughner was mentally unfit to stand trial. He ruled on Tuesday that months of forcibly medicating him to treat his schizophrenia made him competent to understand the gravity of the charges against him and assist in his own defense.
Loughner is expected to be sentenced to life in prison without parole.