On August 3, 1970, prosecutors in Los Angeles were in the second week of presenting their murder case against Charles Manson and three young women accused of killing the actress Sharon Tate and six others. A thousand miles away, at the Federal Building in Denver, President Richard Nixon was attending a conference on crime control for federal and state officials. Nixon, with Attorney General John Mitchell standing at his side, worried aloud that the Administration’s “batting average” in convincing Congress to enact crime legislation had been “very poor.” He mentioned that he had just watched “Chisum,” a new John Wayne movie, and mused about why Westerns were so appealing. “One of the reasons is, perhaps—and this may be a square observation—is that the good guys come out ahead in the Westerns; the bad guys lose,” Nixon suggested.

Then Nixon shifted to the Manson trial, and what he believed was a contrary tendency, especially among the young, to “glorify and to make heroes out of those who engage in criminal activities.” That attitude, Nixon lamented, had been on display in the front-page coverage of Manson. “Here is a man who was guilty, directly or indirectly, of eight murders without reason,” he said. (One murder was tried separately.) “Here is a man yet who, as far as the coverage was concerned, appeared to be a rather glamorous figure, a glamorous figure to the young people who he had brought into his operations.”

Chaos ensued. The sitting President had done something that then seemed an unthinkable breach of ethics: he had opined on the guilt of a criminal defendant. As Jeff Guinn described it in “Manson,” his 2013 biography, “Within moments, Nixon’s remarks flashed across national wire services.” The jury for the Manson trial was sequestered and prohibited from reading newspapers or watching TV news, Guinn explained, “so prosecutors felt reasonably certain that the jurors wouldn’t immediately learn what the president said.” That didn’t stop defense lawyers from demanding a mistrial; surely, they argued, jurors would see the front-page headlines: “MANSON GUILTY, NIXON DECLARES,” blared the Los Angeles Times; “NIXON’S TATE TRIAL FUROR,” said the Los Angeles Herald Examiner. Ronald Hughes, a lawyer for one of the women accused alongside Manson, said, “When the President of the United States finds it necessary to comment on the guilt or innocence of a defendant, it indicates that defendant is past the point of getting a fair trial.” (The judge overseeing the case said that he saw no basis for declaring a mistrial.)

For their part, Administration officials scrambled to walk back the gaffe. As the New York Times described the events, minutes after “the assembled newsmen rushed to file their reports,” the White House press secretary, Ronald Ziegler, summoned them to a damage-control session. The President, Ziegler insisted, had intended to use the word “alleged”; he hadn’t meant to express a view on Manson’s guilt or innocence. Mitchell, the Attorney General, weighed in, asserting that Nixon had not “made a charge or implied one.” The President, en route back to Washington, had Mitchell and the White House counsel, John Ehrlichman, draft a statement backing down even further. “We had quite a time on Air Force One trying to work out a correction,” Nixon’s chief of staff, H. R. Haldeman, wrote in a diary entry. The plane circled while the President’s men hashed out the language. “The last thing I would do is prejudice the legal rights of any person, in any circumstances,” Nixon’s statement read. “To set the record straight, I do not know and did not intend to speculate as to whether the Tate defendants are guilty, in fact, or not. All of the facts in the case have not yet been presented. The defendants should be presumed to be innocent at this stage of their trial.”

The Manson episode surfaces now and again, when a President oversteps in commenting on pending cases. It came up in 1988, when Ronald Reagan was criticized for saying that he expected two former national-security aides indicted in the Iran-Contra affair, Oliver North and John Poindexter, would be acquitted. “I still think Ollie North is a hero,” Reagan said. “I just have to believe that they’re going to be found innocent because I don’t think they were guilty of any law-breaking or any crime.” (North and Poindexter were both found guilty of multiple charges, but their convictions were vacated on appeal.) Even in that situation, with the President speaking out on behalf of his own aides, the White House was rattled. Chief of staff Howard Baker, playing cleanup, said that Reagan was volunteering only “personal views” and that his “official position is that the system must operate.”

Democratic Presidents have made similar blunders—and faced some backlash. When the Obama Administration was under fire for seeking to return the accused 9/11 mastermind Khalid Sheikh Mohammed to the United States for trial, in 2009, President Barack Obama offered a blustery defense: “I don’t think it will be offensive at all when he’s convicted and when the death penalty is applied to him.” Former law professor that he was, Obama quickly backpedalled. “What I said was people will not be offended if that’s the outcome,” he clarified. “I’m not prejudging.” (Mohammed is facing charges before a military commission in Guantánamo Bay; the case is still pending.) In 2021, during jury deliberations in the trial of the former Minneapolis police officer Derek Chauvin, who was ultimately convicted of murdering George Floyd, President Joe Biden said that he was “praying the verdict is the right verdict, which is—I think it’s overwhelming, in my view.” Biden took pains to add, “I wouldn’t say that unless the jury was sequestered now, not hearing me say that.” When quizzed about the appropriateness of the remarks, the White House press secretary, Jen Psaki, claimed that Biden was not “weighing in on the verdict.”

All these loose-lipped Presidents, of course, look like models of reticence compared with Donald Trump. He has opined on prosecutions with relish, at length, and with no evidence of being hamstrung by presumption-of-innocence niceties. Nixon’s point about the problem of casting Manson as a celebrity was, at bottom, a paean to the importance of an orderly judicial process. His language, in retrospect, was milquetoast. And, of note, Nixon was commenting on a state-level prosecution. Trump, by contrast, has demanded that his own Department of Justice pursue individuals whose guilt he has pronounced obvious in advance.