STANLEY “Tookie” Williams, the co-founder of the notorious Crips street gang, is due to be executed today after Arnold Schwarzenegger, the California Governor, yesterday refused to grant the prisoner clemency.

Lawyers for Williams said that they were appealing to the US Supreme Court, which could grant a last-minute stay of execution. Los Angeles was bracing itself for retribution should the execution take place.

Mr Schwarzenegger said: “Is Williams’s redemption complete and sincere, or is it just a hollow promise? Without an apology and atonement for these senseless and brutal killings, there can be no redemption. After studying the evidence, I could find no justification for granting clemency.”

Just before the governor announced his decision, the 9th US Circuit of Appeals denied Williams’s request for a reprieve, saying among other things that there was no “clear and convincing evidence of actual innocence”. Williams, 51, is due to be killed by lethal injection at 12.01am today, local time. At 6pm local time yesterday Williams, who says that he is innocent of four murders, was expected to be served his final meal in San Quentin prison. Williams is also allowed to spend time with a spiritual adviser until 45 minutes before his execution. Then the prison warden will arrive to take down his last words.

City leaders fear that the death of Williams could provoke the kind of unrest that followed the 1992 not-guilty verdict in the trial of police officers involved in the beating of Rodney King.

Raymond “The Hatchet Man” Locket, a member of the Westside Harlem Crips and a former associate of Williams, told LA Weekly: “Took die, the city fry. That’s the word on the streets.” The Los Angeles Police Department said that it doubted the depth of support for Williams, especially among new-generation gang members. A police spokesman said that the force would remain vigilant but not deploy more officers. The execution, if it goes ahead, will take place before about 50 witnesses. Williams has not asked for family members or friends to be present, but hundreds are expected to gather outside the prison.

He will be strapped to a trolley and hooked up intravenously to two bags of saline solution. Williams will be injected by a sedative, followed by potassium chloride, to paralyse him, then pancuronium bromide to induce a heart attack. During his 24 years in prison, Williams has written children’s books with anti-violence messages, been nominated for the Nobel Peace Prize and been the subject of a television film.

But Lora Owens, the stepmother of Albert Owens, a 26-year-old cashier murdered by Williams, has campaigned against clemency. Mr Owens was shot twice in the back by Williams as he lay on the floor. “I will be there in the name of Albert and his father, watching the execution,” she said.

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