In their book on impeachment, @tribelaw and @JoshuaMatz8 explain that the drafters of the Constitution specifically decided . . .
Those who acts as judge and jury of the president are elected officials.
They answer to constituents, and those constituents are basically all Americans.
Trump expects, ultimately, to be tried in the Court of Public Opinion, which is where he is comfortable. He doesn’t inhabit the world of facts. He enacts political theater.
(Remember: Impeachment doesn't mean removal. The Senate removes with a 2/3 vote.)
The Constitution requires the Chief Justice to preside over the Senate trial, which (I assume) was intended to contain some of the political theater and inject actual law.
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