A federal judge on Tuesday was pressed to publicly reveal secret communications between the U.S. Justice Department and the court that could shed light on the Trump administration’s controversial move to fire and criminally investigate former FBI acting director Andrew McCabe.

The watchdog group Citizens for Responsibility and Ethics in Washington asked U.S. District Judge Reggie Walton to unseal three sets of transcripts in which government lawyers spoke alone with Walton outside the presence of other lawyers. Those transcripts could shed light on the status of the probe, along with any problems prosecutors faced, in a drawn-out investigation Walton has criticized for leaving McCabe in “limbo.”