The first question is, interestingly, something on which there is considerable debate among Constitutional scholars.
But what if the impeachment process starts when the president is, well, president, and ends when he isn’t? It’s not clear!
“Once Trump’s term ends on Jan. 20, Congress loses its constitutional authority to continue impeachment proceedings against him — even if the House has already approved articles of impeachment.
“Therefore, if the House of Representatives were to impeach the president before he leaves office, the Senate could not thereafter convict the former president and disqualify him under the Constitution from future public office.
“The reason for this is found in the Constitution itself. Trump would no longer be incumbent in the Office of the President at the time of the delayed Senate proceeding and would no longer be subject to “impeachment conviction” by the Senate, under the Constitution’s Impeachment Clauses. Which is to say that the Senate’s only power under the Constitution is to convict — or not — an incumbent president.”
“To be sure, a former officer may no longer be ‘removed’ even upon conviction by a two-thirds vote. But that has no bearing on whether such an ex-officer may be barred permanently from office upon being convicted. That separate judgment would require no more than a simple majority vote.
“Concluding otherwise would all but erase the disqualification power from the Constitution’s text: If an impeachable officer became immune from trial and conviction upon leaving office, any official seeing conviction as imminent could easily remove the prospect of disqualification simply by resigning moments before the Senate’s anticipated verdict.”
So, the short answer is we don’t really know if you can impeach a former president. The Constitution leaves it open to interpretation and it’s never been tested in the real world before.
But there’s a piece of Tribe’s argument that helps us get close to an answer on the second question I posed above: Even if you can impeach a former president, why do it?
On its face, it doesn’t make a ton of sense. Holding a trial to decide whether a former president is guilty of impeachable offenses and should be removed from office when that person has already left office is sort of odd — and seemingly counterproductive.
Except that voting to remove Trump from office isn’t all Senate Republicans could do. See, if 67 senators vote to convict and remove Trump, then another vote could be held on whether to ban Trump from seeking any future public office. And that vote would only require a simple majority (50+1) of senators to pass.
Which would be a BIG deal — especially because a) Trump has made no secret of his interest in running for president in 2024 and b) (obviously) early polls on that race suggest he would be a clear frontrunner to be the Republican nominee.
Banning Trump from ever seeking public office again, which would be a virtual certainty in a 50-50 Senate where Vice President Kamala Harris breaks ties. And would not only make the 2024 Republican primary a wide open affair but also ensure it is free of the toxic presence of Trump. (Side note: Even if Trump is banned from running for office again, there’s nothing to stop Donald Trump Jr. or Ivanka Trump from running.)
There’s motivation, then, for McConnell to support the attempt to impeach, remove and ban Trump — even after January 20. That doesn’t mean McConnell will throw his support behind the move — or, even if he did, that it would happen.
But is does suggest that there is some logic behind trying to impeach even a former president.