The judge overseeing the prosecution of former national security adviser Michael Flynn recused himself from the case this week, though the reasons for his decision remain a mystery.

Rudolph Contreras, a judge on the U.S. District Court in Washington, D.C., recused himself from the Flynn case on Thursday, according to court filings.

Contreras will be replaced by Emmet Sullivan, a Bill Clinton appointee.

Flynn pleaded guilty last Friday to lying in an interview with the FBI about conversations he had last year with Russia’s ambassador, Sergey Kislyak. As part of the plea deal, Flynn agreed to cooperate with Special Counsel Robert Mueller’s expansive Russia investigation.

A spokeswoman for the court which Contreras oversees declined to offer specifics on his recusal.

“The court generally does not disclose reasons for recusal,” Lisa Klem told The Daily Caller.

Contreras, an Obama appointee, is also a judge on the secret federal court which decides on requests for wiretap warrants on foreigners and U.S. citizens.

In Sept. 2016, a judge on the court — the Foreign Intelligence Surveillance Court — granted as least one wiretap warrant against former Trump campaign adviser Carter Page. The judge who ruled on that warrant remains unidentified, as is usually the case with FISC proceedings.

TheDC asked Klem if Contreras’ position on the FISC court had anything to do with his recusal but she provided the statement about the court system’s policy against discussing recusals.

The wiretap warrant against Page has come under scrutiny because of the possibility that it was based on allegations made in the anti-Trump dossier financed by the Clinton campaign and Democratic National Committee. It has been reported that the dossier was cited in the Justice Department’s application for the warrant on Page, an energy adviser who worked as a volunteer on Trump’s campaign.

Page is accused in the dossier of having served as the campaign’s backchannel to the Kremlin. He has vehemently denied the allegations.

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