The prosecution have called for Norwegian killer, Anders Behring Breivik to be considered insane, and committed to a mental institution.
If found sane the right-wing extremist, who killed 77 people in a bomb and gun attack last July, would face a maximum prison sentence of 21 years, although this can be extended if he is still considered a threat to society.
If he is found to be insane he faces indefinite detention in a secure ward at a high security prison.
Two psychiatric evaluations of the 33-year-old have reached contradictory conclusions; one that he is a psychotic paranoid schizophrenic, while a second said he suffered from a narcissistic personality disorder but was not psychotic, and could therefore be held criminally responsible.
If he is found insane Breivik has said he will appeal. He admits the killings but said he should not be found guilty as they were an act of self defence against those who promote Muslim immigration.