Lawyers for Terrance "Terry" Williams had asked Chief Justice Ronald Castille to recuse himself because Castille supervised Williams' murder case and signed off on the 1986 death penalty prosecution.
At the moment, Williams has a reprieve of his scheduled execution. A Philadelphia judge has thrown out the death sentence after finding new evidence last week that prosecutors withheld important evidence from defense lawyers and the jury.
But prosecutors have appealed that decision to Castille's court. The execution warrant is valid through Wednesday, should the Supreme Court overturn the lower court's ruling and restore the death sentence.
Castille on Monday filed an order denying the recusal motion. He does not plan to comment, a court spokesman said.
Williams' lawyers argued in their motion that Castille has a clear conflict of interest. And they said he has shown antagonism toward the Federal Community Defenders office in denying recusal motions in some of the 45 other death penalty cases he oversaw as Philadelphia's district attorney.
"As district attorney, he wrote a note approving that his staff seek the death penalty against Terry," said Shawn Nolan, assistant chief of the defenders' capital habeas unit. "We thought recusal was a reasonable request under these circumstances. Justice Castille disagreed."
Williams, 46, would be the first person executed in Pennsylvania in 50 years who had not abandoned his appeals.
He's on death row for killing two men by age 18. He now says both victims, a 56-year-old church deacon and a 50-year-old sports booster, had been sexually abusing him. He has acknowledged that older men were paying him for sex as a teen.
The Philadelphia jury sentenced Williams to death for fatally beating the deacon, Amos Norwood, in a cemetery. Jurors heard only that the motive was robbery. Williams and an accomplice were caught after using a credit card they'd taken from the victim.
However, the accomplice, Marc Draper, testified last week that he told police and the trial prosecutor that Norwood and Williams had a sexual relationship. He said they didn't want to hear it and told him to stick to the robbery motive at trial.
Common Pleas Judge M. Teresa Sarmina found that notes unearthed last week from the original police files, along with the trial prosecutor's notes, confirmed Draper's account. She vacated Williams' death sentence on Friday, five days before the scheduled execution.
Philadelphia District Attorney Seth Williams filed an appeal by day's end. He said the death penalty should be rare but he believes it is justified in the Terrance Williams case.
There are about 200 people on Pennsylvania's death row. Only three people have been executed since the death penalty was restored in 1978.
Norwood's widow and five jurors are among those who have signed petitions to spare Williams' life. The jurors said they would have voted for a life sentence had they known of the abuse allegations and understood that a life sentence means life in Pennsylvania. Lifers never have a chance for parole, but juries do not have to be told that.