BOSTON (AP) — A federal appeals court has agreed to a defense request to remove the judge who was set to preside over the trial of accused gangster James “Whitey” Bulger.

The 1st U.S. Circuit Court of Appeals ruled Thursday that U.S. District Judge Richard Stearns must step down from Bulger’s case.

Bulger’s lawyers argued that Stearns should be removed from the case because he was a federal prosecutor in Boston in the 1980s. At the time, Bulger was working as an FBI informant while allegedly committing crimes, including murder.

Bulger claims he received immunity for his crimes from another federal prosecutor who worked in the same office as Stearns while Bulger was giving the FBI information on the Mafia.

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