President Trump has been impeached, and the trial seems unlikely to begin until he is no longer the President. There is some dispute about whether the Senate can try an impeachment of an ex-official. But it has done so in the past, most famously in the case of ex-Secretary of War William Belknap, and for reasons adequately covered by others I think that is proper.
If it does, there comes a secondary procedural question. Who presides? According to Article I, Section 3, normally "The Vice President of the United States shall be President of the Senate," and in her absence, other Senators preside. But "When the President of the United States is tried, the Chief Justice shall preside." Should we think of the trial of ex-President Trump as the trial of a President?
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