Vice President Harris has, on the stump, taken to calling President Trump a “felon” and invoking the mantle of a tough former prosecutor, but if she wins the presidency she could immediately face a fraught legal and political question — whether to pardon the 45th president.

The possibility that a President Harris could soon weigh whether to pardon Trump or let the legal cases against him run their course has come into greater focus as her political fortunes rise. It is now almost a certainty that Special Counsel Jack Smith’s two federal cases — the January 6 and Mar-a-Lago ones — will stretch past Election Day. 

The government has suffered setbacks in both. Judge Aileen Cannon dismissed the 40 charges handed up in south Florida. She found that Mr. Smith’s appointment by Attorney General Garland was unconstitutional. The special counsel, though, has appealed. The high court’s immunity ruling upended the January 6 case and sent it back to Judge Tanya Chutkan for further findings.

It is not difficult, though, to imagine Mr. Smith’s fortunes improving from this summer swoon. The United States Court of Appeals for the 11th Circuit could overrule Judge Cannon and reinstate the charges that she dismissed. In the District of Columbia, Mr. Smith could find his footing — possibly by slimming down his indictment — and get his case back on track.

In any event, Mr. Smith is dug in for months, maybe even years, of litigation. By the time either case reaches a jury, Ms. Harris could be ensconced at the White House. There, she would have at her command the pardon power, one of the most unrestrained prerogatives of the office. The Constitution ordains that the president “shall have Power to grant Reprieves and Pardons for Offences against the United States.”

The Supreme Court judged the power to pardon to be in the “conclusive and preclusive” authority of the president and entitled to “absolute” immunity. In 74 Federalist, Hamilton wrote that the “benign prerogative of pardoning should be as little as possible fettered or embarrassed. 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.”

One pardon in particular was central to Mr. Smith’s contention that Trump could be tried for acts undertaken while he was in office — the one extended by President Ford to his predecessor, President Nixon, for Watergate. The special counsel reasoned that Ford’s pardon and Nixon’s acceptance of the pardon “rested on the understanding that the former President faced potential criminal liability.” Chief Justice Roberts’s majority opinion did not find that compelling.

Ford’s pardon of Nixon ignited a firestorm, with the Times calling it a “profoundly unwise, divisive, and unjust act.” Allegations that it was transacted via a secret or corrupt deal led to Ford testifying before the House Judiciary Committee, the first sitting president to do so before Congress since Lincoln. 

Some historians surmise that the unpopularity of the pardon is a reason Ford lost the 1976 election to Jimmy Carter, though Gallup finds that over time Americans grew to believe that the reprieve was just. In 2001, the John F Kennedy Library gave Ford its “Profile in Courage Award,” singling out Ford’s pardon of his predecessor as praiseworthy.  

In a 2004 interview with the journalist Bob Woodward, Ford explained that he “had no hesitancy about granting the pardon because “I felt that we had this relationship and that I didn’t want to see my real friend have the stigma.” While Trump gave money — $6,000 — to Ms. Harris’s re-election bid for attorney general, the two do not have the kind of personal relationship that suggests a fondness reminiscent of the one Ford felt for Nixon. 

On the campaign trail, Ms. Harris has leaned into her experience as a prosecutor, and touts herself as someone who has convicted “perpetrators of all kinds. … So, hear me when I say I know Donald Trump’s type.” That preroration has prompted chants of “lock him up” from the Democratic throngs, which suggests a limited appetite for clemency. When a crowd chanted that at a rally in Wisconsin, though, Ms. Harris shushed the faithful and declared, “We’re gonna let the courts handle that.”

The vice president could be leery of providing the 45th president with grist for challenging the January 6 prosecution, which he claims is politically motivated and keyed to wounding President Biden’s chief political rival. Judge Chutkan last month denied Trump’s motion to dismiss the charges on that basis, but rhetoric that suggests the Biden administration has a rooting interest in a conviction could make Mr. Smith’s job that much more difficult. 

The question of a pardon has also haunted the current occupant of the White House, Mr. Biden. He has promised that he would not issue a pardon to his son Hunter, who has been convicted of lying on a gun purchase form and faces tax charges that are set to be tried this fall. On Wednesday, the White House spokeswoman, Karine Jean-Pierre, refused to disclose whether Mr. Biden has discussed the possibility of a pardon with Ms. Harris.  

Ms. Harris, though, could have compelling reasons to issue a pardon to Trump as a means to unify a country that’s become deeply divided between those who support the former president and those who oppose him. Trump’s denunciations of “lawfare” have resonated with millions of Americans, and he raised a record sum after his conviction in District Attorney Alvin Bragg’s hush-money case. By pardoning Trump, Ms. Harris would put to rest the controversy over Mr. Smith’s pursuit of the 45th president.  

A future President Harris would, like Ford, have to face voters in a bid for a new term. In any event, she would lack the power to pardon Trump in the two state criminal cases levied against him — those are not reckoned as “offenses against the United States.”