President Trump’s victory over Vice President Harris in November’s election delivered him immunity from federal criminal prosecution — but the highest office does not provide protection from civil litigation, at least at the moment. 

That means that Attorney General Letitia James’s fraud judgment against Mr. Trump for more than $450 million — with interest it now totals more than $500 million — still hangs over the president. New York State’s top prosecutor secured the verdict without trying the matter before a jury and, following the election, she said she has no plans to cease her efforts to make Mr. Trump pay up.

Ms. James’s win came after Judge Arthur Engoron ruled that Mr. Trump’s valuations of his properties — among them Mar-a-Lago and Trump Tower — were marked by “persistent fraud.” Judge Engoron handed down draconian sanctions on Mr. Trump, the Trump Organization, and his two elder sons.

The ruling amounted to a signature victory for Ms. James, who claimed that Mr. Trump had mastered “the art of the steal.” She ran for office vowing to shine a “bright light into every dark corner of his real estate dealings,” and called him a “con man” and a “carnival barker.” For his part, Mr. Trump has called Ms. James “racist.”

Judge Engoron’s punishments were severe and wide-ranging. An independent chaperone was installed to monitor the privately held family business, and restrictions were imposed on the ability of the Trumps to conduct business in New York, their core stomping ground since Mr. Trump’s father, Frederick, established the roots of their real estate empire at Queens. Judge Engoron, who also imposed a gag order on Mr. Trump, wrote that the “frauds found here leap off the page and shock the conscience,” and that Mr. Trump’s “complete lack of remorse borders on pathological.”

The gag order prevented Mr. Trump and his attorneys from criticizing Judge Engoron’s principal law clerk, Allison Greenfield, who sat next to Judge Engoron on the bench and whom the Trump team accused of bias, “rolling her eyes,” and “co-judging.” Things got off to a bad start when Mr. Trump referred on social media to Ms. Greenfield as “Schumer’s girlfriend,” without verification that she had any relationship with the former Senate majority leader. Ms. Greenfield, active in Democratic circles, was elected judge herself in November.

Mr. Trump appealed the verdict to New York’s first court of appeals, the Appellate Division First Department. During oral arguments before that review tribunal, the judges appeared skeptical of Judge Engoron’s verdict. One ventured that the “immense penalty in this case is troubling.”

Another reasoned that the determinations of fraud “almost entirely concerned subjective evaluations of properties and businesses,” making the underlying actions less a riot of fraud than a “commercial dispute.” 

The Supreme Court, in Clinton v. Jones, has ruled that a sitting president is not immune from civil litigation of the kind that Paula Jones launched against President Clinton. The highest court reckoned that the distraction posed by civil suits is not onerous enough to warrant the protection that the Department of Justice has come to believe is “categorical” when it comes to criminal cases. 

The lawsuit at issue in the case, brought by Ms. Jones, did in the end create a significant distraction. It resulted in a deposition of Mr. Clinton, in the course of which he lied about his Oval Office sexual encounters with Monica Lewinsky, precipitating his impeachment. Ripples from the case extended to 2016, when Ms. Jones was brought to a debate between Mr. Trump and Secretary Clinton, in an effort to embarrass Mrs. Clinton about her husband’s sexual transgressions at a time when Mr. Trump was reeling from the exposure of the “Access Hollywood” tape.

Clinton was decided by a unanimous court. All nine justices held that the “separation-of-powers doctrine does not require federal courts to stay all private actions against the President until he leaves office. Even accepting the unique importance of the Presidency in the constitutional scheme, it does not follow that that doctrine would be violated by allowing” civil lawsuits.

In Trump v. United States, in contrast, the high court held that official presidential acts are presumptively immune from prosecution. If the civil fraud verdict against Mr. Trump is upheld on appeal, Ms. James could enjoy a boost just as she is reportedly weighing a run for Gracie Mansion, though the Times relates that a decision to run is “far from assured and is not imminent; some close to her stressed her ambivalence, if not reluctance.”

Ms. James, in a press conference after Mr. Trump’s win in November, vowed to “fight back” against the new administration. That prompted one of the president’s informal legal advisers, Mike Davis, to declare on a podcast his “dare” to Ms. James to “try to continue your lawfare against President Trump in his second term.” Mr. Davis added: “Listen here, sweetheart. We’re not messing around this time, and we will put your fat a– in prison for conspiracy against rights. I promise you that.”

Ms. James can claim to be the last prosecutor standing against Mr. Trump after Special Counsel Jack Smith retreated; Manhattan’s district attorney, Alvin Bragg, saw his case ended in an “unconditional discharge”; and Fulton County’s district attorney, Fani Willis, was disqualified for her secret romance. She is appealing. Mr. Trump also faces more than $80 million in liability in cases where juries found that the president sexually abused and defamed a writer, E. Jean Carroll.  

If Mr. Trump secures a reversal of Judge Engoron’s verdict on appeal, though, it would amount to yet another litigation victory against a prosecutorial foe. The 47th president will also appeal the 34 “guilty” verdicts secured by Mr. Bragg in the hush money case, a process that will transpire while Mr. Trump sits in the Oval Office.

Mr. Trump also faces no fewer than eight civil suits, all before Judge Amit Mehta at the District of Columbia. Judge Mehta held in January 2022 that Mr. Trump was not immune from those suits because his actions of January 6, 2021, were private and not in the ambit of the duties of the presidency. Mr. Trump pardoned nearly all of the more than 1,500 January 6 criminal defendants.