You implicitly argue that because the Justices of the Supreme Court weren't impeached because of the DSD, it must be because they did nothing wrong. Frankly, at least one of them should have been impeached for judicial misconduct by 1861, but there were more important things on the minds of the wartime Congress.
Justice Curtis, I agree. Per SC rules, he could not publish his opinion until finalized and delivered to the Court Reporter.
The Congress was trying to keep for being arrested by the military.