California governor Arnold Schwarzenegger has heard a final plea to halt the execution of ex-gang leader Stanley "Tookie" Williams.
Williams's case has generated a public campaign calling for clemency
Mr Schwarzenegger must make a decision based on the clemency hearing before the penalty is carried out next week.
Williams, co-founder of the notorious Los Angeles Crips street-gang, was sentenced to death in 1981 for the murder of four people, which he denies.
A number of high-profile supporters have backed the appeal for clemency.
WILLIAMS' CELEBRITY SUPPORT
Bishop Desmond Tutu
Rev Jesse Jackson
Williams faces death by lethal injection on 13 December at San Quentin prison, north of San Francisco.
Correspondents say there is mounting pressure on the California governor to grant clemency, something he has not done in the previous two cases brought before him.
Prosecutors and lawyers for Williams each had 30 minutes to present their case to Mr Schwarzenegger.
Speaking after the hearing, defence lawyer Peter Fleming Jr said he believed Williams was of more use alive to spread an anti-gang message than he would be dead.
Asked if he was optimistic about his client's chances, he replied: "I'm still frightened to death."
Prosecutor John Monaghan told reporters the evidence in the case was "truly overwhelming" and that Williams' crime was so brutal "it simply justifies the ultimate penalty".
Williams co-founded the notorious Crips gang
Mr Schwarzenegger is expected to issue his decision on whether to grant clemency - which would commute the death sentence to life without parole - by letter.
The hearing came a day after the governor had hospital tests to investigate an irregular heartbeat.
Earlier this week, South Africa's Winnie Mandela became the latest high-profile personality to call for clemency for Williams.
While in jail Williams, 51, has won praise for his anti-gang books, earning several Nobel Peace Prize nominations for his teachings.
His supporters range from Oscar-winning actor Jamie Foxx and rap star Snoop Dogg (himself a former Crips member) to Bishop Desmond Tutu and the Reverend Jesse Jackson.
Since the United States resumed the death penalty in 1977, governors have granted clemency 230 times, according to the Death Penalty Information Center.
What do you think Governor Schwarzenegger should do? Clemency or allow the death penalty to be carried out?
Should Stanley "Tookie" Williams's anti-gang activities since he was imprisoned outweigh his violence past?
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