[HarleyLady27]

How can you impeach if he isn’t president anymore?

[jjotto]

There is a reason for impeachment of someone not currently holding office.

Constitution Article 1, Section 3:

"...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..."

[PIF]

President by declaration?