TUCSON - Jared Loughner sat slumped at the defense table in a federal courtroom here Tuesday and said over and over in a soft, slightly slurred voice: "I plead guilty."

He said it 19 times in all as he was asked by U.S. District Judge Larry Burns if he was guilty of crimes in the savage mass shooting at a supermarket just north of the city. The attack claimed the lives of six and wounded 13, including then-U.S. Rep. Gabrielle Giffords.

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Jared Loughner court hearing

Loughner's plea came 19 months after the massacre at a meeting of Giffords' constituents. In exchange, prosecutors agreed not to seek the death penalty. Loughner, 23, would serve life sentences with no chance of parole. Sentencing is scheduled for Nov.15.

Tuesday's guilty plea did not come as a surprise. News of the proposed agreement had leaked Saturday, but that did not diminish the intense emotions and compelling testimony at the hearing.

The courtroom was packed. The crowd spilled into an overflow room on another floor where the hearing could be seen on closed-circuit TV. Many of the surviving victims and their families sat quietly on one side of the courtroom. On the other side was Loughner's mother and a man who appeared to be his father, huddled by the wall in the back row. News reporters had come from around the country.

Loughner, who was diagnosed as schizophrenic, was found competent by Burns to stand trial. Then, the defendant pleaded guilty to 19 of the 49 crimes he was charged with in the Jan. 8, 2011, shooting -- spelled out in a 14-page plea agreement, each page of which he had initialed.

He was guilty of two counts of murder of a federal employee, one count of attempted assassination of a member of Congress, two counts of attempted murder of a federal employee, four counts of causing the death of a person at a federally sponsored event, and 10 counts of injuring a person at a federal event. The agreement stipulates that Loughner cannot be sentenced to death. He faces life in prison with no chance of parole for the charges of murder and attempted assassination, and up to 10 and 20 years on the others.

After the hearing, many of the victims said they agreed with the plea but made it clear that there was no end to the tragedy.

Susan Hileman, who tried unsuccessfully to use her own body to shield 9-year-old Christina-Taylor Green from the bullets, said Tuesday that she is relieved that she will never have to see Loughner again, spared from having to testify at a lengthy trial.

"What I want is Christina. Nothing can give me that. This is the most I can hope for," Hileman said.

Others were more ambivalent.

Roger Salzgeber, a retiree who attended Giffords' event with his wife, Faith, and helped take down Loughner, said before the shooting that he opposed the death penalty. Now, he can't help feeling that justice has been shorted, though it helps that Loughner would get life without parole.

"I'm not that person who would say, 'Just put him on a gurney and kill him,'" he said. "But there's a part of me that saw what I saw, and it feels somewhat unfulfilled."

During the hearing, Loughner sat quietly, dressed in prison khakis, without restraints, his red-brown hair in a buzz cut. He answered questions with short sentences or a simple yes or no. That contrasted with his May 2011 court appearance, when he was removed from the courtroom after an outburst in which he said that he had watched Giffords die.

The plea agreement followed a nearly hourlong hearing in which a federal prison psychologist detailed Loughner's slow progress from madness to competency. Burns found Loughner to be competent, then turned to the plea agreement, with Loughner admitting guilt and saying he was making the plea willingly. He will return to a Missouri prison pending his sentencing.

The case may not end there, however. The Pima County Attorney's Office could still prosecute Loughner in state court, which could lead to multiple death penalties. Assistant U.S. Attorney Wallace Kleindienst, the lead prosecutor in the case, said that there had been no input from County Attorney Barbara LaWall in the plea agreement, and she had not informed the U.S. Attorney's Office about what she plans to do.

LaWall was unavailable for comment on the case Tuesday. Isabel Burruel Smutzer, a spokesperson for LaWall's office, said that the case is still a federal matter and that county prosecutors have yet to review it. She declined to address any next steps.

At a news conference after the hearing, John Leonardo, newly appointed U.S. attorney for the District of Arizona, said some people may want the death penalty for Loughner, but the victims had been consulted and, given the circumstances, the plea deal was the best way to speed up healing.

"Mr. Loughner will spend the rest of his life in prison with no chance of parole," Leonardo said.

Several victims spoke at the news conference. Pam Simon, who was a staffer in Giffords' office and was wounded in the attack, asked for a "common-sense discussion of who should carry arms."

Randy Gardner, another shooting victim, decried the lack of mental-health care for people like Loughner.

"We really have to be our brother's keeper here and reach out and get them help," Gardner said.

Most of Tuesday's hearing dealt with just that: Loughner's mental health.

Dr. Christina Pietz, Loughner's psychologist, spoke about her near-daily visits with Loughner since March 2011, and how he progressed from a paranoid young man hearing messages from radio and television to a coherent person aware of what he had done.

Loughner sat quietly as Pietz described her review of Loughner's journal, computer entries and other material. From that, she concluded that he had shown signs of depression since 2006 and may have developed symptoms of schizophrenia in his junior year of high school.

From 2008 to 2010, Loughner's parents and friends became concerned that he would commit suicide because of his depression and started a suicide watch. In one video he filmed of himself, Loughner said he was so depressed he wanted to assassinate someone.

Pietz said when she diagnosed Loughner with schizophrenia after the shooting in 2011, he was "disappointed, upset." Pietz said he told her he wished he took depression medication.

In early months of treatment, he persisted with his belief that he had killed Giffords, and when he realized he hadn't, he considered himself a failure. He questioned moments and images in the surveillance video showing him in the act. He said of himself, "Jared is a failure."

Eventually, he began to express remorse. "I especially cried about the child," Pietz quoted him as saying about Christina-Taylor Green. Loughner told Pietz that he deserved the death penalty and that he realized the consequences of his actions. Once during a group-therapy session, in responding to a question about what he would do when he got out of prison, Pietz recalled him saying, "I'm not ever going to get out."

Since being imprisoned, Loughner has expressed interest in having a job, which Pietz said was a sign of mental competency. He now works in prison, rolling socks and underwear in towels for inmates.

Pietz said she believed Loughner to have a factual, rational understanding of the role of a jury, a judge, prosecutors and judicial proceedings. Loughner is also able to orient time and place and no longer shows signs he is hearing voices or other auditory stimuli.

If he were moved to the general prison population, Pietz said, she would not be concerned he would harm anyone as long as he is medicated. However, she added, "My concern is someone will harm him."

Pietz emphasized that Loughner had never been forcibly medicated in prison. She called it passive involuntary medication because he had never refused it.

At one point during Loughner's treatment, Judy Clarke, Loughner's lead attorney, objected to forced medication, saying the government was trying to make an end-run around the law by using the dangerousness argument to make him take the same drugs used in restoration of schizophrenics.

The 9th U.S. Circuit Court of Appeals briefly took Clarke's side and stopped the medication while it reviewed the issue. But after another incident at the hospital in July 2011, prison officials decided to require the medication again, and this time, the 9th Circuit upheld the medication.

Clarke did not cross-examine Pietz on Tuesday.

Burns then asked his questions, turning to Loughner and saying, "He is a different person in his appearance and his effect than when I first laid eyes on him."

At the end of May, when Loughner appeared for his first competency hearing, he had to be removed from the courtroom after going into a rant in which he indicated that he believed he had killed Giffords.

"Thank you for the free kill. She died in front of me. Your cheesiness," he said.

Burns found Loughner competent to stand trial Tuesday. Competency is defined as being able to understand the court proceedings and assist his attorneys with his defense.

"My personal observations of him leave no questions in my mind that Loughner knows what's going on today," Burns said.

Loughner consistently answered Burns' questions about each of the counts. He also told the judge that he understood he was giving up the right to contest his guilt and that the mandatory minimum penalty was a life sentence.

"Is that what you want to do? Have you made that choice to give up those rights and plead guilty?" Burns asked. Loughner, looking attentively at the judge, replied, "Yes."

News of the pending plea agreement spread quickly, resulting in a gaggle of media descending on the Tucson courthouse to cover the event. The courtroom was packed, and roughly 80 people watched the hearing from an overflow room.

Tucson shooting victims filled four rows, or about a third of the courtroom, with Barber, who took Giffords' seat in the U.S. House, sitting in the front.

Earlier Tuesday, Mark Kelly, Giffords' husband, said in a statement that he and Giffords were satisfied with the proposed plea agreement, adding that they had been in touch with the U.S. Attorney's Office throughout the case.

The couple did not attend the hearing; they have been out of the country, hosting a long-planned cruise of the Mediterranean that docked in Rome on Monday. They have not yet returned home to Houston, where Giffords has been undergoing outpatient therapy for her brain injury.

"The pain and loss caused by the events of Jan. 8, 2011, are incalculable," Kelly said. "Avoiding a trial will allow us -- and we hope the whole southern Arizona community -- to continue with our recovery and move forward with our lives."

Republic reporters Amy B Wang, Michelle Ye Hee Lee, Rebekah Sanders, Bob Ortega, Jaimee Rose, Lindsey Collom, Dennis Wagner and 12 News staffer Joe Dana contributed to this article.