Anony Mous
The Constitution Annotated is the resource provided by the U.S. Government via the Library of Congress for understanding our Constitution. I would agree that it's not the final authority, but it is more than simply "one" opinion published by "a" government.
The characterization of high crimes and misdemeanors with regard to impeachment as fundamentally criminal acts is a misconception commonly repeated in Trump's defense.
This has never been true for judges under Article III, Section 1 of our Constitution which provides that judges of the supreme and inferior courts "shall hold their offices during good behavior."
It's also not true of the office of President as Deschler's Precedents of the U.S. House of Representatives notes with regard to Nixon: "...the grounds for Presidential impeachment need not be indictable or criminal." (I can provide the full quote if context is needed.)
Article I, Section 2 of our Constitution grants the House sole power in impeachment and Section 3 grants the Senate sole power to try impeachments. There is no Constitutional provision for judicial review and therefore unlikely that the Supreme Court would get involved.