WASHINGTON (CN) - The Supreme Court heard arguments Monday in a complicated case asking when potentially biased judges should recuse themselves to avoid violating due process rights.
The high court will try to draw a constitutional line while considering a situation involving a former prosecutor who later served as a judge in a case that he personally approved the death penalty for as a district attorney.
The case before the court Monday involved Terrance Williams, who committed two homicides - the first when he was 17, and the second three months after his 18th birthday.
Williams has said that both men he killed sexually abused him, but that evidence was suppressed in his second trial, leading to a conviction and a death sentence.
The focal points of the case are former Philadelphia District Attorney Ronald Castille and prosecutor Andrea Foulkes. Castille approved the death penalty for Williams in response to a detailed memo from prosecutors, including Foulkes, arguing for the death penalty.
Justice Anthony Kennedy asked Williams' attorney to formulate a rule for when recusal would be required.
"When the prosecutor has direct personal involvement in a substantial decision in the case, and the issue before the court reflects upon that decision," responded Stuart Lev, assistant federal defender for Philadelphia.
"A fair trial in a free society does not allow the prosecutor who prefers the charges to become the judge of that," Lev later added.
Years after greenlighting Williams' death penalty, Castille did just that. He launched a successful bid for a seat on Pennsylvania's Supreme Court and, during his campaign, openly advocated for capital punishment, citing the 45 people he sent to death row while he served as district attorney - including Williams.
That alone would not be grounds for recusal, Lev said.
"It's an added weight to the pile. But by itself, it would not be a due process violation," Lev said.
Some 30 years after he approved the death penalty for Williams, Castille sat on a tribunal that considered Williams' appeal. Though Castille's vote was not the deciding one, Williams claims that the inclusion of a potentially biased jurist on the tribunal violated his due process rights.
The tribunal denied his appeal, with Castille joining the majority opinion, though a state judge would later grant Williams a stay of execution after two more appeals.
In another twist, Foulkes suppressed mitigating evidence from Williams' defense attorney, whom he met only the night before his trial started.
Though Williams perjured himself by denying he knew one of the victims, Amos Norwood, he later claimed in an evidentiary hearing during his first appeal that Norwood had sexually abused him, along with other underage boys.
There was independent evidence to verify Williams' claim. A review of the district attorney's files in the case allegedly revealed that both Foulkes and the police knew about Norwood's attraction to teenage boys and his proclivity to acting on that attraction, but sanitized that evidence during trial.
It was also later revealed that Williams' co-defendant, Marc Draper, falsely testified that the homicide was motivated by a robbery, and that he did so in response to threats from prosecutors to charge him in an unrelated, unsolved murder case.
Lev argued before the U.S. Supreme Court that because Williams met his trial lawyer only the day before his trial started, he did not have the opportunity to discuss which facts - including the alleged sexual abuse - could have bolstered his defense.
"The prosecutor, in fact, told the trial judge that there wasn't any independent evidence of sexual abuse by this man of other people, correct?" Justice Sonia Sotomayor asked Lev.
"Correct," Lev responded.
Justice Samuel Alito questioned Lev about how the high court should deal with the fact that Castille was not the standard bearer for the Pennsylvania Supreme Court ruling in Williams' case.
Lev argued that, because no one outside of the Pennsylvania justices know what happened in the decision-making process, the court should make a rule that "anyone should be entitled to a panel of appellate judges where there are no judges with bias."
"If we agree with you," Alito asked, "doesn't that lead inevitably to the rule that a majority of the judges on a multi-judge panel have the authority to require the recusal of a colleague?"
"I - that's an interesting question," Lev responded, drawing laughter.
Williams wants the Pennsylvania Supreme Court to reconsider his case fresh without Castille, who is now retired, Lev said, adding that the Supreme Court could only order such relief because of a constitutional violation.
Ronald Eisenberg, deputy district attorney for Philadelphia, argued that the current test requires a look at the totality of the circumstances and "an intolerable probability of actual bias in the case."
Sotomayor pressed him on the issue.
"Don't you think, as a reasonable probability, that the appearance of impropriety is just present?" she asked.
"After 30 years, maybe everybody wouldn't see it that way," Eisenberg said, "especially if they looked at the rest of [Castille's] record."
"There are many instances where judges or justices worked on an issue, spearheaded an issue, fought for legislation, for example, for years and years and years, even may have had it named after them, and then sat in judgment on the constitutionality or scope of that legislation," Eisenberg added.
Most people would see as much potential for bias in that situation, but the reason it is not a constitutional violation pertains to previous precedent, he said.
The court's laws "recognize that judges are human beings, they have prior lives, and that we don't want to have a situation where the only people who can become judges and sit on cases are people with no prior experiences," Eisenberg said.
The Supreme Court must decide if Castille was constitutionally required to recuse himself from the case and, if so, what relief Williams is entitled to.
Though Democratic Pennsylvania Gov. Tom Wolf suspended capital sentences, Williams remains under restrictive conditions reserved for death row inmates. The high court is expected to issue a ruling this spring.