California's Supreme Court Wednesday refused to stop the execution of convicted killer Stanley "Tookie" Williams, the founder of the Crips street gang who became an anti-gang crusader while on Death Row, a court spokeswoman said.
Williams' attorney, Jonathan Harris, told CNN he was disappointed by the court's 4-2 decision.
But Harris said he plans to make a compelling case before Gov. Arnold Schwarzenegger or his staff at a December 8 clemency hearing to commute Williams' sentence to life in prison without parole.
Schwarzenegger or a federal court could still intervene to stop the execution of Williams, who would turn 52 December 29.
The defense petitioned the high court November 10 to reopen the case.
Williams' lawyers alleged there was faulty testing of shell casings found near the scene of a triple slaying at a motel in 1979, said Natasha Minsker, director of death penalty policy for the American Civil Liberties Union.
She called the forensic evidence used in the case "junk science."
The defense also contended informants lied to prosecutors and sought to re-examine other evidence, she said.
Williams, who is scheduled to die by injection December 13, was convicted in the 1979 killings of four people. The first victim was a 17-year-old Los Angeles convenience store clerk.
Williams also was convicted of killing an immigrant couple and their daughter while stealing cash from their motel. Both cases were handled in a single trial, and he was sentenced to death in 1981.
After his imprisonment, Williams denounced gang violence and began writing children's books with an anti-gang message, donating the proceeds to anti-gang community groups.
He said he was trying to prevent young people from making the choices he did, which led to a life of crime.
"The only thing that I was doing was destroying my own kind," Williams said in an interview from his cell at San Quentin State Prison.
Actor Jamie Foxx portrayed Williams in a 2004 made-for-television movie, "Redemption: The Stan Tookie Williams Story."
On Tuesday, Virginia's governor spared the life of Robin Lovitt a day before he was to become the 1,000th person executed in the United States since capital punishment resumed in 1977.
Lovitt's sentence was commuted to life in prison without parole for stabbing a man to death with a pair of scissors during a 1988 pool hall robbery.