In an order Monday, D.C. District Judge Amy Berman Jackson called for the Trump administration to provide her with a copy of Trump's executive order granting Stone clemency, and "whether it involves the sentence of incarceration alone or also the period of supervised release."
Jackson said her order followed questions that were specifically raised by the U.S. Probation Office, and ordered the government to submit the order by Tuesday -- when Stone was originally set to begin his 40-month prison sentence at a federal corrections institution in Alabama.
But Scott Anderson, a fellow in Governance Studies at the Brookings Institution, argued that any attempts to impose limits on the president's constitutional pardon power could prove fruitless.
"I have no doubt a corrupt use of the pardon power could be the basis for an impeachment," Anderson said. "But I'm not sure if there's other legal restrictions Congress could easily put on it."
Both Anderson and Joshua Geltzer, a former DOJ and White House official who serves as Georgetown Law School's Executive Director of the Institute for Constitutional Advocacy, noted that debate over how to check a president potentially abusing their pardon powers dates back as far as the drafting of the U.S. Constitution.
"The Framers did anticipate that this power, as extraordinary as it is, could be abused by a president," said Geltzer. "In a debate between George Mason and James Madison, Madison's answer was that abuse of that power would be grounds for impeachment. I think in some ways it shows how far we've fallen that the notion of the House and Senate checking a president through use of impeachment power when the president has done something so ostentatiously awful -- the fact that feels unavailable right now is a real problem."
Anderson said an alternative approach lawmakers could take that might survive constitutional muster would be to pass legislation requiring more transparency and disclosure in the clemency process -- such as demanding presidents hand over all records related to pardons and commutations to Congress, as a potential incentive for avoiding politically-motivated acts of clemency.
"Those sorts of restrictions, even where the president has substantial capacity to act unilaterally, usually are seen as constitutionally acceptable because they're not really imposing a serious restriction," Anderson said.
Separate from a check on the president's lawful exercise of a constitutional power, however, it's not without modern precedent for the motives behind a president's decision to grant a pardon to be the subject of criminal investigation.
After former President Bill Clinton pardoned the wealthy financier Marc Rich on his last day in office in 2001, the incoming Bush Justice Department tasked prosecutors with investigating the move as a possible act of corruption. The probe was closed, however, after no evidence of criminal activity was uncovered.
It's unlikely a similar probe would be initiated by Trump's own Justice Department, however. Even as Democrats have alleged the clemency was an overt move by Trump to reward Stone in his refusal to cooperate with special counsel Mueller's investigation, the White House has countered that Trump was instead motivated by his overall disdain for the Russia investigation in the first place.
During Barr's confirmation hearing in January 2019, he stated he believed it would be a "crime" for a president to issue a pardon in exchange for the recipient's promise to not incriminate him.
But in an interview with ABC News last week, Barr made clear he would give deference to the president should he make the decision to pardon Stone or commute his sentence while at the same time defending Stone's prosecution as "righteous."
"I think it's the president's prerogative," Barr said. "It's a unique power that the president has. And it's certainly something that is committed to his judgment. But as I say-- I felt it was-- appropriate prosecution and I thought the sentence was fair."