More than 30 years after Eleanor Urbati, a white Hingham resident, reluctantly helped convict a 19-year-old black man of first-degree murder, she testified in court Friday that the deliberations were biased.

Urbati, 81, a former switchboard operator, told a Plymouth Superior Court judge that on the first day of deliberations in 1986, a juror told the all-white panel that he believed Darrell Jones was guilty of the Brockton murder because he was black.

Urbati, who was the last holdout to break a hung jury, testified that when the unnamed juror said Jones was guilty, she asked him why.

“I said, ‘Are you saying that because he is black?’ And he said, ‘Yes,’ ’’ Urbati said in court. “I was just kind of shocked.”

Justice Thomas McGuire Jr. summonsed Urbati to court as part of a reexamination of the Jones verdict, in what is believed to be the first such review in Massachusetts since the US Supreme Court ruled in March that a trial judge must pry into typically secret discussions if there is evidence of racial bias. Other members of the jury were questioned last month.

Urbati’s allegations were first aired in a 2016 investigation published by the New England Center for Investigative Reporting that examined Jones’s third motion to vacate the murder conviction without possibility of parole.

Jones says he’s innocent, alleging that police tampered with a videotaped interview of a key witness shown at his trial to remove exculpatory evidence. The tape is important because none of the eyewitnesses testified in court that they were sure Jones was the shooter.

Jones also says that his lawyer at the time, now deceased, failed to adequately represent him by, among other things, forcing him to sit in a so-called prisoner’s dock 10 feet behind him, rather than beside him. Prosecutors offered no motive or physical evidence to convict him, court records show.

McGuire said he first heard about the bias allegations in June and was required to call jurors back to court despite the decades that have passed.

The hearing was prompted by a Supreme Court decision involving a Colorado man, Miguel Angel Pena Rodriguez, who appealed his 2007 conviction for unlawful sexual contact after learning that a juror had said he thought Pena Rodriguez was guilty because he was Mexican, and “Mexican men take whatever they want.” State law has a similar requirement based on a 2010 ruling from the Massachusetts Supreme Judicial Court.

McGuire said court officials tried to reach all the jurors, but not all could be located or could make it to court. In early August, three others testified that they couldn’t remember whether bias was present in their deliberations. Too much time had passed, they said.

Urbati said she did not attend the first hearing because she hadn’t received a summons. On Friday, she said, she remembers when the juror allegedly admitted to racism in the jury room. She regrets not speaking up earlier and couldn’t say why she kept quiet — perhaps because she’d been instructed by the judge not to discuss jury deliberations or because she didn’t think it would make a difference, she said.

She testified Friday that the color of Jones’ skin didn’t come up again during jury deliberations. She said the same juror said later, “I’ll say anything just to get out of here.”

Jones’s attorney, John Barter, said Urbati’s testimony was credible and should convince the judge that Jones did not have an impartial jury.

Jessica Kenny, a Plymouth County assistant district attorney, said Urbati’s testimony isn’t enough to prove racial bias. Among her arguments, she said, it’s not clear the statements were made, because other jurors couldn’t confirm them. Even if they were uttered, she said, it’s unclear whether they were made sarcastically or humorously. It’s also possible, she said, that the jury “was simply commenting on the state of the evidence in the identification that had been made.”

McGuire said he would consider the testimony as part of Jones’s motion and make a determination at a later date.

Urbati has long regretted changing her vote to guilty in Jones’s trial, and she cried during his sentencing decades ago. “I feel terrible he has been in jail all this time,” she said. “I didn’t think he did it.”

After the hearing, Urbati greeted several of Jones’s family members in the hallway. Among them was Jones’s mother, Edna Sawyer, who had driven from her home in Virginia. The two hugged each other and remembered crying together in the bathroom after Jones’ conviction.

“I’m sorry,’’ Urbati said.

“Don’t be sorry,’’ said Sawyer. “The truth will come one day. And I love you, all right.”

This story was co-published with the Boston Globe.