Jared Lee Loughner is expected to plead guilty to a shooting rampage in early 2011 that resulted in six dead and 13 injured, including then-Rep. Gabrielle Giffords (D-Ariz.).

As part of an agreement, Loughner's plea is expected to happen during a U.S. District Court hearing in Arizona Tuesday in which prosecutors and Loughner's lawyers seek to prove that the 23-year-old suspect is mentally competent to stand trial. Loughner then is likely to plea guilty to the January 2011 shooting.

The details of the agreement have been scant but, if Loughner does plead guilty, he could face life imprisonment but not the death penalty.

Giffords, who stepped down in the later half of 2011, was the target of the shooting rampage. She suffered a gunshot wound to the head from close range, but survived.

In a statement Tuesday, Giffords's husband, astronaut Mark Kelly, said that he and his wife had been in contact with prosecutors in the case and approved of the deal.

"We don't speak for all of the victims or their families, but Gabby and I are satisfied with this plea agreement. The pain and loss caused by the events of January 8, 2011 are incalculable," Kelly said in a statement according to The Associated Press.