Are there any limits on the president’s pardon power?


The question, which has generated vigorous debate this summer, has new relevance in view of special counsel Robert Mueller’s continuing investigation into “any links and/or coordination between Russian government and individuals associated with the campaign of President Donald Trump.” No one can know where Mueller’s investigation is leading, but the possibility of criminal indictments cannot yet be ruled out.


Trump has tweeted that the president’s pardon power is “complete.” At first glance, the Constitution seems to support him, at least for the most part: “The President … shall have Power to grant Reprieves and Pardons for Offences against the United States, except in Cases of Impeachment.”


While that sentence leaves some open questions, you could easily read it to mean that the president has the authority to pardon anyone he likes, with one exception: He cannot stop an impeachment proceeding.


The very question was debated by two of the most far-sighted thinkers in the founding era.


George Mason played a large role in the Constitutional Convention in Philadelphia, but he was dissatisfied by the final document, and he refused to sign it. At Virginia’s all-important ratifying convention, he contended “that the president ought not to have the power of pardoning.”


In particular, Mason objected that “he may frequently pardon crimes that were advised by himself.” He complained: “If he has the power of granting pardons before indictment, or conviction, may he not stop inquiry and prevent detection?”


That seems like a formidable objection, but, as usual, James Madison, his fellow Virginian and the closest thing to the Constitution’s father, was one step ahead of him.


Gently, Madison pointed to “one security in this case to which gentlemen may not have adverted.” The security was that “if the President be connected, in any suspicious manner, with any person, and there be grounds to believe he will shelter him, the House of Representatives can impeach him; (and) they can remove him if found guilty.” In Madison’s view, “This is a great security.”


In that way, Madison directly responded to Mason’s specific concern. But he also seemed to do him one better. Mason was focused on the most egregious cases, in which a president pardoned people for committing crimes that he himself “advised” (apparently in the sense of personally suggesting and helping to plan). More broadly, Madison urged that if the president was merely “connected, in any suspicious manner,” with someone who was engaged in wrongdoing, and if he decided to “shelter” (meaning pardon) him, then the president could be impeached.


In recent weeks, there have been many useful discussions of whether a president has the authority to pardon himself. Whatever the answer to that specific question, the more general point is plain: The president has no authority to abuse the pardon power. If he does, impeachment is the appropriate remedy. In that important respect, the pardon power is hardly “complete.”


On the meaning of the Constitution, it’s not a good idea to quarrel with James Madison.


Cass R. Sunstein is a Bloomberg View columnist. He is the author of “#Republic: Divided Democracy in the Age of Social Media” and a co-author of “Nudge: Improving Decisions About Health, Wealth and Happiness.” Readers may email him at csunstein1@bloomberg.net.