Trump indictment marks a first for U.S. democracy. It may not be the last.

No ex-president had been indicted before Thursday, prompting debate over whether the case will ultimately strengthen or weaken the rule of law.

Former president Donald Trump speaks at the Conservative Political Action Conference in Maryland on March 4. The expected prosecution of Trump shatters an unwritten American political norm. (Jabin Botsford/The Washington Post)

President Warren G. Harding was in danger of facing criminal charges in 1921 in the Teapot Dome bribery scandal, but he died in office first. Richard M. Nixon faced almost certain indictment after the Watergate scandal forced his resignation in 1974, but his successor and former vice president, Gerald Ford, pardoned him.

Those cases were as close as any current or former president had ever come to criminal charges in the 234 years since George Washington took office, until Donald Trump’s indictment on Thursday by a Manhattan grand jury.

The expected prosecution of Trump shatters an unwritten American political norm and brings the United States more in line with dozens of other nations, including democracies such as South Korea, Brazil, France, Italy and Israel, that have criminally charged, convicted and in many cases jailed former leaders.

It also left U.S. historians and legal scholars puzzling over what the new legal landscape will look like for future presidents. Several said it was a moment that could open a new era of legal peril for former presidents, including the possibility of tit-for-tat, politically motivated prosecutions.

“Anyone who is worried that this will be the beginning of a pattern of indicting past presidents is right to be worried,” said Jill Lepore, a Harvard University historian and author.

“The problem is not doing it but making it a habit,” she said. “If it happens once, the rule of law has held. If it happens after every presidency, the rule of law is lost.”

Trump and his backers allege that the charges — which have not been unsealed, but which are expected to involve possible violations of campaign finance laws when Trump paid $130,000 in hush money to an adult film actress with whom he had an affair — have already taken the country down that path.

Trump, who denies all charges, has insisted on his social media platform, Truth Social, that he is the victim of “horrible radical left Democrat” investigations. Before the announcement of the action against Trump, Sen. Eric Schmitt (R-Mo.) tweeted that Trump’s potential indictment is “some Third World Banana Republic lunacy and a very, very dangerous road to go down.” After the indictment news broke Thursday, Trump wrote in a post: “THE USA IS NOW A THIRD WORLD NATION.”

But many scholars of the Constitution and the executive branch say the charges demonstrate the strength of U.S. democracy, proving that not even a former president is above the law.

“It’s the failure to indict Mr. Trump simply because he was once the president that would say we were well on the way to becoming a banana republic,” said Laurence Tribe, a Harvard University legal scholar who taught Barack Obama and advised his presidential campaign and administration. “Those who fear that indicting a former president would say that U.S. democracy is in trouble have it exactly backwards and upside-down.”

Michael Beschloss, a presidential historian and author, said the long U.S. tradition of not indicting former presidents is partly because “in general, presidents did not misbehave, in a criminal sense, to a degree that would have made that seem urgent.”

“Part of it has also been an unfortunate view that ex-presidents deserve some kind of monarchical immunity that normal citizens do not,” he said. “How do you explain to someone who steals toothpaste from a drugstore that they are more subject to American law than a president is?”

Trump’s New York indictment may not be his last. He and his allies are under investigation by the district attorney in Fulton County, Ga., for efforts to overturn the 2020 presidential election. A Justice Department special counsel, Jack Smith, is also investigating those efforts, as well as the possible mishandling of classified information.

The precedent-setting indictment in Manhattan is likely of more concern for former presidents than it is for those seeking the job or currently doing it.

Although there is no law against prosecuting political candidates, the Justice Department has a policy of being extremely cautious about seeming partisan or influencing the outcome of elections. The Justice Department also follows a policy dating to 1973 against prosecuting sitting presidents.

Harding and Nixon are the two presidents who may have come closest to being prosecuted, with Nixon’s greatest legal peril coming after he left office. (One president, Ulysses S. Grant, was arrested in 1872 for speeding in downtown Washington in his horse-drawn carriage, but reportedly never showed up for his court appearance on the misdemeanor infraction.)

Jon Grinspan, a curator of political history at the National Museum of American History, said Andrew Johnson, in office from 1865 to 1869, was also accused of breaking the law, though not by a prosecutor. Johnson was impeached by the House of Representatives for violating a law requiring him to obtain Senate consent to replace his secretary of war. But he was acquitted at his Senate trial.

“The failure of his impeachment in 1868 meant that it just went away,” Grinspan said. “Sometimes impeachment scratches the itch, and they don't move on from there.”

Ford’s pardon of Nixon a month after his resignation headed off the possibility of an indicted ex-president in handcuffs for the first time.

In his pardon, Ford said: “The tranquility to which this nation has been restored by the events of recent weeks could be irreparably lost by the prospects of bringing to trial a former President of the United States.”

Ford said prosecuting Nixon would have caused “prolonged and divisive debate over the propriety of exposing to further punishment and degradation a man who has already paid the unprecedented penalty of relinquishing the highest elective office of the United States.”

Beschloss said Trump spent time with Nixon after he left office, writing to him that he had been a “great” President and urging him to move to Trump Tower in New York.

“In retrospect, I now believe that Ford never should have pardoned Nixon, at least so immediately,” Beschloss said. “It gave later presidents, especially Trump, the idea that they were somehow above the law.”

Claire Jerry, also a curator at the National Museum of American History, said that in the nearly half-century since Nixon’s resignation, public opinion toward the presidency has been changing. The notion of the presidency as an institution “above reproach regardless of who’s in the office” has been increasingly challenged.

She said the rise of social media and 24/7 news has given people access to immediate information that was not available in the past. “The issues are not new, but our ability to know about the issues is certainly different now,” she said.

Several historians noted that impeachments were once almost as rare as criminal indictments. But, Lepore said, members of the House of Representatives have introduced resolutions calling for the impeachment of every president since Ronald Reagan was inaugurated in 1981.

Bill Clinton was impeached but not convicted. Trump was impeached by the House twice and acquitted by the Senate both times. Republicans have introduced multiple resolutions to impeach President Biden, though they have not gone anywhere.

“Before (1981), you didn’t just holler, ‘Impeach him!’ when you didn’t like the president,” Lepore said.

Grinspan said he did not believe the indictment against Trump was political. But he saw parallels between ending the country’s record of not prosecuting ex-presidents and the rise of impeachments.

“Any weapon that’s brought into politics on one side shows up on the other pretty quickly, so I would not be surprised if we see further indictments of presidents and political figures down the line,” he said.

Even some critics of Trump have questioned whether the Manhattan district attorney’s office should have sought an indictment against Trump over his hush money payments to Stormy Daniels.

Some critics have said those charges are trivial and flimsy compared to others in separate investigations into Trump’s finances and his attempts to overturn the 2020 election. They argue that prosecuting Trump for the Daniels payments risks making the judicial system appear politicized and damaging public confidence in U.S. rule of law.

Edward Luce, Washington-based columnist for the Financial Times, wrote a recent piece under the headline, “It’s unwise to get Trump on a technicality.”

“The prospect that Manhattan’s district attorney could briefly handcuff Trump … has so excited his detractors that it seems to have triggered a collective loss of judgment,” he wrote, adding that charging Trump with “fiddling with business expenses” would help him and undermine the justice system.

“It would reinforce the MAGA conspiracy theory that ideological prosecutors working for the deep state are determined to derail Trump’s 2024 campaign,” Luce wrote.

Critics have also said an indictment could lead to the kind of violence Trump’s supporters engaged in during the Jan. 6, 2021, attack on the U.S. Capitol. Trump has called for protests and criticized those who have insisted they be peaceful.

Wilfred M. McClay, a historian at Hillsdale College, a conservative Christian school in Michigan, answered questions about a potential Trump indictment by quoting Abraham Lincoln, who “contended that if the American nation were ever to be destroyed, it would be destroyed by suicide, by internal disintegration, and not by an external foe.”

“All of us will have much to answer for,” McClay said in an email, “if we choose to fight to the death over matters of relatively little import, while the nation’s vast and looming problems, including our very capacity to deal effectively with our external foes, go largely unaddressed.”

Others said Trump is accused of serious crimes that warrant prosecution, and that the rule of law only survives when it is applied equally to everyone.

“I would rather live in a country where presidents and ex-presidents are held strictly to account than a country in which they are allowed to cut dangerous corners out of anxiety that justice might seem too ‘politicized,’” Beschloss said.