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Tarney is one of five Fleet captains selected to be a judge at Gaius Baltar's trial . When Admiral Adama tries to prevent President Roslin from having to testify about her renewed use of chamalla, Tarney and Franks overrule him. Later, he wants to hear Lee Adama's testimony. However it is uncertain how he votes on the issue of Baltar's guilt (TRS: "Crossroads, Part I" & "Part II").
Evidently, he had not boarded Pyxis by the time of the Battle of the Ionian Nebula in which it was destroyed by the Cylons. He goes on to be one of the members of the new Quorum made up of ship captains, but it is unknown what ship he represents (TRS: "Islanded in a Stream of Stars").