In brief, knowing they must take that the oath should sober senators, but there's no cure if it doesn't.
Now, follow along...
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FTR: One senator/juror was Johnson's son-in-law, while another would have become president if Johnson had been convicted.
From Judge Louderback's 1933 trial…
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But again, no matter how much bias a senator may show, there's no remedy (apart from the ballot box).
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nytimes.com/1999/01/23/us/…
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