A federal judge on Thursday ordered a new trial for three former Memphis police officers found guilty of charges related to the fatal beating of Tyre Nichols, a 29-year-old FedEx worker, in 2023. She cited concerns about the appearance of bias, pointing to comments that the judge who presided over the trial reportedly made afterward, suggesting that one of the defendants was a gang member.

Last fall, a federal jury acquitted the former officers of the most serious charge, that they had violated Mr. Nichols’s civil rights by causing his death. The jury found them guilty on federal witness tampering charges.

But just days before the three men were to be sentenced, Judge Mark Norris abruptly recused himself from the case.

Court documents unsealed on Thursday, as well as the judicial order, show that the defendants requested a new trial after the U.S. attorney’s office disclosed conversations that took place after the verdict. One of Judge Norris’s law clerks had been shot during an apparent carjacking in October, days after the verdict, and the judge repeatedly expressed frustration with the police investigation and lack of federal charges in that case to federal prosecutors, according to the documents.

Then, in a May meeting with the prosecutors, Judge Norris suggested that one of the defendants in the Nichols case was a member of a gang, according to the documents. He went on to say that the gang might have been responsible for the shooting of his law clerk, because the law clerk had been staying at the home of another clerk who had worked on the case.