Crips co-founder Stanley Tookie Williams moved a step closer to the death chamber Wednesday when the California Supreme Court refused to reopen his case in four murders and halt the state's highest-profile execution since the death penalty was reinstated.

In a last-ditch legal move, Williams alleged that shoddy forensic testing and other errors wrongly sent him to San Quentin State Prison, where he is scheduled die by lethal injection Dec. 13.

Lawyers for the convicted murderer who claims he redeemed himself on death row by penning anti-gang books for kids wanted to re-exam ballistics evidence that showed Williams' shotgun was used to kill three people during a Pico Rivera motel robbery in 1979.

The defense claimed the forensic evidence was "junk science," but prosecutors said that allegation was "based upon innuendo, supposition and the patent bias of his purported expert, not upon allegations of fact."

"The extraordinary relief Williams sought is reserved for those cases which have legal merit," said Nathan Barankin, spokesman for Attorney General Bill Lockyer.

The court voted 4-2 without comment to deny Williams' petition. Chief Justice Ronald George voted to reopen the case.

"We think the chief justice's dissent highlights the seriousness of the issues raised," defense attorney Jonathan Harris said. He was unsure whether he would ask the federal courts to intervene again.

Williams, 51, is in line to become one of three California condemned inmates to be executed within months unless he is granted clemency by Gov. Arnold Schwarzenegger, or a federal court intervenes.

The ruling came as death penalty opponents rallied around the state urging the governor to spare Williams' life because of his death row redemption.

"We're all remaining optimistic, we're all remaining prayerful," Bonnie Williams-Taylor, the ex-wife of Williams and mother of one of his sons, said at a rally in Los Angeles.

Williams was condemned in 1981 — four years after the death penalty was reinstated.

He has maintained his innocence in the killings, claiming among other things that fabricated testimony sent him to death row.

The California Supreme Court, the federal trial and appellate courts, and the U.S. Supreme Court have ruled against him in earlier appeals, which set the stage for the execution.

Williams is asking for clemency from Schwarzenegger for killing Yen-I Yang, Tsai-Shai Chen Yang and Yu-Chin Yang Lin in the motel robbery, and Albert Owens, a 7-Eleven clerk gunned down in a separate killing.

Schwarzenegger has agreed to hear Williams' clemency petition in his office Dec. 8. If clemency is granted it would commute his sentence to life without parole.

"What I want to do is make sure we make the right decisions, because we're dealing here with a person's life," Schwarzenegger said Wednesday.

While in prison, Williams has been nominated five times for a Nobel Peace Prize and four times for the Nobel Prize for literature for his series of children's books and international peace efforts intended to curtail youth gang violence.

Williams and his high school friend, Raymond Washington, started the Crips in Los Angeles in 1971 and it grew into one of the nation's most notorious street gangs.

Williams had also sought records about an accomplice who testified against him in the murder of Owens. That witness, now imprisoned in Canada for murder, testified that they robbed a Whittier convenience store where Williams shot Owens twice in the back. Defense lawyers questioned the witness' credibility.

Justice Joyce Kennard joined George in the dissent. Justices Marvin Baxter, Ming Chin, Kathryn Mickle Werdegar and Carlos Moreno voted to deny the petition. The court has one vacancy awaiting Schwarzenegger's appointment.

The case is California v. Williams, S004365.