hard case to prove all up hill as der trumpster is the chief executive. Go back a ways
https://www.neh.gov/humanities/2013/mayjune/feature/burr-versus-jefferson-versus-marshall
A remarkable aspect of the trial—one unique in American history—was the president’s micromanagement of the prosecution from the White House. The reasons for Jefferson’s personal involvement are unclear. Generally speaking, he was reluctant to delegate authority, and he also may have lacked full confidence in the government’s lawyers. And since he had already declared Burr guilty, he may have felt compelled to prove himself right. In any case, Jefferson’s numerous letters to George Hay, the federal attorney who was nominally in charge, contain detailed instructions about trial strategy, evidence, and witness interrogation. Jefferson even forwarded a batch of blank pardons to be used, at Hay’s discretion, to elicit evidence from reluctant witnesses. One such was Erick Bollman, a Burr associate, who pointedly refused in open court to accept a pardon for the crime of treason, a crime that he clearly did not commit. Burr’s lawyers took the occasion to blast the prosecution—and the president.

Jefferson’s involvement, which became common knowledge during the trial, turned out to be one of Burr’s main lines of defense. It also provided some of the trial’s most dramatic moments, notably when Luther Martin, one of Burr’s lawyers, denounced the author of the Declaration of Independence for behaving like “a king of Great Britain” and for unleashing “the dogs of war, the hell hounds of persecution” against an innocent man for personal reasons.
no impeachment, no charges and in american law precedent matters.

blank pardon forms? not the first time and in this case maybe not the last.