I believe that the Senate can also dismiss the impeachment charge through an abbreviated proceeding, as was done with the Clinton impeachment.
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You may be right but I doubt any proceedings would be abbreviated. The lure of cameras and high political theater trumps all in DC. They will want to maximize their exposure given such a golden opportunity to become a household name.
Its not about doing the right thing for the country. Its about doing the right thing for their careers.
I can easily see the Senate GOP and Democrats from red states summarily voting to reject a Trump impeachment on the basis that hearings were unfairly held in secret without the opportunity for the President or his party to cross-examine witnesses or to subpoena documents and witnesses themselves.
Such an approach would also play to the Senate's institutional frame of mind that being older, wiser, and more experienced, Senators often have to correct mistakes and oversights by the House and its impetuous membership. Congress and state legislatures both display that dynamic, which has a large if seldom appreciated role in American legislative politics.