The “ultimate punishment” isn't losing office.
In a criminal trial, a defendant stands to lose life (capital cases), liberty or property.
To call loss of office the "ultimate" punishment is silly.
Moreover, Art 1, sec 3 👇 says that. . .
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After removal, the person can be subjected to a criminal trial.
The idea that removal from office first requires proof of a crime under the standards of a criminal court make mo sense/ criminal trial occurs AFTER removal . . .
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Removal is for corruption and abuse of power.
Criminal court comes later.