The trial of Anders Behring Breivik has ended in Norway with a walkout by families of victims in protest at his attempts to justify the massacre.
As he took the stand to explain why he killed 77 people last July, some 30 people filed out of the courtroom.
Saying he had acted to stop a Muslim invasion, he asked to be considered sane and to be acquitted.
Judges will deliver their verdict on 24 August. The prosecution is asking for Breivik to be deemed insane.
Breivik's lawyer, Geir Lippestad, said his client had been driven by extreme politics.
Breivik's address to the court was not broadcast.
Trond Henry Blattman, who lost his 17-year-old son in the Utoeya shootings and is now spokesman for a victims' support group, had already made clear that the boycott was aimed at Breivik and not the court itself.
The BBC's Lars Bevanger, who was in court, said the group felt there was no more that Breivik could add.
"He has a right to talk. We have no duty to listen," another support group member Christian Bjelland told Norwegian media.
Earlier, the trial's final day heard poignant testimony from people affected directly by the attacks.
Friday morning's proceedings were carried live on television but cameras were also withdrawn when the trial resumed after lunch to hear testimony from several people injured or bereaved by Breivik.
Breivik admits killing 77 people and injuring 242 on 22 July when he bombed government buildings in Oslo before shooting young Labour Party supporters at a camp on the island of Utoeya.
His request for acquittal is a legal formality because he does not accept the charges of terrorism and premeditated murder against him.
Memorials to Breivik's victims will be built at the two attack sites, the government announced on Friday.
It was, Mr Lippestad stressed, for the court to decide whether his client had been sane at the time of the attacks.
"The mother of these actions is not violence, it is an extreme, radical, political attitude, and his actions must be perceived from the point of view of right-wing extremist culture," he said.
The fact that "safe, little Norway would be hit by such a terror attack is almost impossible to understand", the lawyer said.
This, he suggested, could explain in part why psychiatric experts had reached different conclusions about Breivik's mental state.
He described his client as an ordinary young man with good friends and colleagues. How, he asked, would a man who was mentally ill have been allowed to join a shooting club?
Nothing in Breivik's life up until the "inferno of violence" on 22 July had indicated he was a violent person, the lawyer argued.
Had violence, not politics, been his main driving force, he could have gone to an Oslo shopping mall, Mr Lippestad said.
As the lawyer spoke, Breivik sat calmly, occasionally sipping water.
The prosecution took the stand again on Friday in response to Mr Lippestad, saying they were not convinced Breivik was psychotic but there was enough doubt to ask for Breivik to be found unaccountable for his actions.
On Thursday, in their closing arguments, the prosecution had called for the killer to be placed in "compulsory psychiatric care", and not sent to prison.
It was worse, they argued, to sentence a psychotic person to prison than to place a non-psychotic person in psychiatric care.
'For my daughter'
Sissel Wilsgard, who was injured by the Oslo bomb, took the stand on Friday afternoon to describe its lasting impact.
Some 100 government employees needed counselling in its aftermath, she was quoted as saying on Twitter by journalist Trygve Sorvaag.
Choking back tears, an unnamed, bereaved mother described what it was like to lose her daughter in the blast.
She said she had decided to attend the trial for the sake of her dead daughter.
"I decided not to be afraid of Breivik. I wanted to follow the trial. I wanted to do it for my daughter."
Tonje Brenna, head of the ruling Labour Party's youth wing, addressed the court as a survivor of the Utoeya massacre.
Remembering friends killed by Breivik, she said: "It says on Facebook that it is their birthday, but I shall never, ever see them again."
A mother who lost a child on Utoeya said all the focus on Breivik's mental health had been draining.
"It's not about his mental health," she told the court. "It's about us never seeing him on the street again."
Lara Rashid, little sister of Bano Rashid who was killed on Utoeya, recalled how Bano had told her: 'You will never lose me. We are sisters."
Correspondents say the atmosphere in the courtroom was charged with emotion and speakers were applauded for their testimony.
Source: BBC News