Special counsel Jack Smith has one hail Mary chance at bypassing Judge Aileen Cannon to get his classified documents case against Donald Trump tried before the election, an expert wrote. And it’s a rare move based on a centuries-old law. A legal expert toldSlate Smith could choose to file a writ of mandamus, an ancient rule that could allow him to skip Cannon and go straight to the court of appeals, asking it to force the judge to reverse her actions. Slate reported it’s essentially a “slap on the wrist,” but it’s “rarely used because district court judges are typically given a lot of leeway t…