Impeaching Officials While They're in Office, but Trying Them After They Leave
From Prof. Michael McConnell (Stanford), a leading constitutional scholar and legal historian:
Much of the discussion of the constitutionality of trying Former President Trump on impeachment charges after he has left office consists of motivated reasoning on both sides that no doubt would be the opposite if partisan roles were reversed. Not enough attention has been paid to the constitutional text, or the timing of this particular impeachment.
Whether a former officer can be impeached is beside the point. Donald Trump was President of the United States at the time he was impeached by the House of Representatives. The impeachment was therefore unquestionably permissible (putting aside any disagreements over the nature of the charges).
Article I, Section 3, Clause 6, states: "The Senate shall have the sole Power to try all Impeachments." The key word is "all." This clause contains no reservation or limitation. It does not say "the Senate has power to try impeachments against sitting officers." Given that the impeachment of Mr. Trump was legitimate, the text makes clear that the Senate has power to try that impeachment.
Article II, Section 4, states: "The President, Vice President and all civil Officers of the United States, shall be removed from Office on Impeachment for, and Conviction of, Treason, Bribery, or other high Crimes and Misdemeanors." This provision does appear applicable only to sitting officers. But it does not limit the power of the Senate to try, which comes from Article I, Section 3, Clause 6. It merely states that removal from office is mandatory upon conviction of any sitting officer. No lesser sanction will suffice.
Article I, Section 3, Clause 7, states: "Judgment in Cases of Impeachment shall not extend further than to removal from Office, and disqualification to hold and enjoy any Office of honor, Trust, or Profit under the United States, but the Party convicted shall nevertheless be liable and subject to indictment, Trial, Judgment and Punishment, according to Law." Read together with Article II, Section 4, this means that the consequence of conviction on impeachment must include removal from office, may include disqualification from future office, and may not include any other sanction. The first sanction is limited to sitting officers, which makes sense. The second sanction is not so limited.
Some argue that the conjunction "and" in Article I, Section 3, Clause 7, implies that the sanction must include both removal and disqualification, and that because removal of a former officer is not possible, disqualification must also not be allowed. But the clause does not say that both sanctions are required; it says that the judgment may not go beyond imposition of both sanctions.
I have not seen any answer to this textual point from those who think the trial of Mr. Trump would be unconstitutional. They ignore the fact that he was properly impeached (at least, insofar as timing is the issue), and they ignore the text of Article I, Section 3, Clause 6, which states that the Senate may try "all" impeachments. They conjure up a limitation on the Senate's power by a misconstruction of the sanctions limitation of Article I, Section 3, Clause 7. And, of course, they bolster their argument with motivated reasoning about consequences for the republic, which are no more persuasive than the motivated arguments coming from the other side.
I suppose that if there were powerful historical evidence that this was not the understanding of the founders, we might have a debate between text and historical understanding. But the historical evidence supports the text. The two British impeachment trials prior to the Constitution both involved former officers, and the first impeachment trial under the new Constitution involved a former Senator. The only respect in which history may clash with text is that history does not support the conclusion that only a sitting officer may be impeached—an issue distinct from the question of trial, and not relevant to the current situation.