He can be impeached anytime, even after leaving office. And he should be. If found guilty, he would lose his pension and SS protection. He could then be prosecuted for usurpation of a federal office. Also, forgery of a draft registration and theft of social security numbers.
Joe is out of office, and he’s getting old.
Maybe he just decided that the option he received of two suicide bullets to the back of his head might be better than living a few more years.