A president’s ability to pardon criminals is an oddity of the U.S. Constitution, one of the few powers conferred on the executive without significant constraint. President Donald Trump has abused this authority — most recently by commuting the sentence imposed on his friend and former campaign adviser Roger Stone for seven felony convictions.

There’s something to be said for enshrining the values of mercy and forgiveness in the nation’s founding document, and for allowing a president to mitigate the vagaries of justice. Alexander Hamilton defended the idea eloquently: “The criminal code of every country partakes so much of necessary severity, that without an easy access to exceptions in favor of unfortunate guilt, justice would wear a countenance too sanguinary and cruel.”

And yet the pardon power has also been an instrument of corruption. For nearly two and a half centuries, presidents have wielded it to excuse politically expedient traitors, mutineers, seditionists, pirates, anarchists, fraudsters and violent criminals of all persuasions. Andrew Johnson pardoned Jefferson Davis. Gerald Ford pardoned Richard Nixon. In a single climactic spasm of clemency, Bill Clinton cleared 140 people on his final day in office, including a notorious tax cheat, a former business partner and his own wayward half-brother.

Trump’s contribution to this shameful canon might seem unexceptional. In addition to Stone’s, he has so far offered pardons or commutations in 35 cases. His compassion has taken in fallen conservative luminaries (Dinesh D’Souza, Joe Arpaio), Fox News causes celebres (Matt Golsteyn, Bernie Kerik), personal associates (Conrad Black, Rod Blagojevich), and the occasional arsonist or murderer. In two ways, though, this isn’t business as usual, and Trump’s record touches new lows.

One is his total lack of regard for the integrity of the justice system. Arpaio had been convicted of contempt of court. Stone had tampered with a witness, lied repeatedly to investigators and threatened a federal judge. Black had been prosecuted for obstruction of justice and Kerik for making false statements to the government. The president has scarcely attempted to offer justifications for overlooking such conduct. In fact, in only six known cases has he bothered to seek the advice of the Justice Department’s pardon attorney, who exists solely for that purpose.

Even more seriously, Trump has abused the power for personal gain. Of those granted clemency, according to one count, 31 had some political or personal connection to the president. Some pardons were merely sordid attempts to rally the base. Others went further. The pardon of Scooter Libby in 2018 was widely interpreted as a signal to witnesses in special counsel Robert Mueller’s investigation that their silence would be rewarded, while the president and his lawyers repeatedly dangled the possibility of clemency to others caught up in the probe — quite possibly a crime in its own right.

As for Stone? Mueller’s report demonstrated that he almost certainly lied (and thus incriminated himself) to protect the president, secure in the knowledge that he’d eventually be taken care of. (Stone denies this.) That Trump has barely bothered to offer an alternative rationale for Stone’s dead-of-night clemency hardly suggests a more honorable motive.

Unfortunately, more such conduct is likely in the weeks ahead, as the president’s first term winds down and the prospect of returning to civilian life looms larger. Trump’s personal lawyer Rudolph Giuliani summed it up plainly enough: “When the whole thing is over, things might get cleaned up with some presidential pardons.”

It’s safe to say that Hamilton did not have such mop-up work in mind in 1788. Yet the Constitution allows effectively no room for lawmakers to constrain the president’s power in this regard. Does that leave any options for Congress? To a limited degree, yes. It could still censure Trump (or indeed impeach him again). It could ask the attorney general to divulge investigative materials in clemency cases involving the president or his associates. And it could aggressively wield its subpoena powers to demand further documents and testimony, even from Trump himself.

Such bureaucratic devices won’t directly impede corruption, of course, and they’ll hardly satisfy the president’s furious opponents. But the objective is to publicly expose misconduct, place the conspirators on record and generally impose a price that might deter future abuses. Beyond that, the Constitution prescribes one further remedy: It’ll happen this year on Nov. 3.

— Bloomberg News