Donald Trump speaks during a campaign news conference at the Old Post Office Pavilion in D.C. on Monday. (Jabin Botsford/The Washington Post)

Donald Trump, you might want to learn something about L.B. Sullivan and the Supreme Court case he inspired.

Sullivan was a city commissioner in Montgomery, Ala., in 1960 when the New York Times published a full-page advertisement criticizing “Southern violators” for infringing on the civil rights of student protesters and Martin Luther King Jr. Sullivan brought a libel suit, claiming he had been defamed, and in the lower courts he won.

Alabama law permitted public officials to recover damages for false statements — and some of the facts in the ad were incorrect — that “tend to injure a person . . . in his reputation” or “bring [him] into public contempt.”

The Supreme Court reversed. “We consider this case,” Justice William J. Brennan Jr. wrote in 1964, “against the background of a profound national commitment to the principle that debate on public issues should be uninhibited, robust, and wide-open, and that it may well include vehement, caustic, and sometimes unpleasantly sharp attacks on government and public officials.”

In other words, welcome to the 2016 campaign.

Republican presidential front-runner Donald Trump has said several times he would “loosen up” libel laws. Listen to his response when The Washington Post editorial board asked him how, exactly, he would change them, which includes discussion of violence against protesters. (Gillian Brockell,James Downie/The Washington Post)

Exaggeration, vilification and even outright false statements, Brennan’s opinion made clear, would not suffice for a public official — or, more to the point for Trump, one in the public eye — to win a defamation claim. “Erroneous statement is inevitable in free debate,” Brennan wrote, and “must be protected if the freedoms of expression are to have the ‘breathing space’ that they ‘need . . . to survive.’ ”

Now comes Trump, proposing, somehow, to restrict that breathing space.

Brennan’s conclusion in New York Times v. Sullivan was that public figures must demonstrate “actual malice” — that is, knowing and reckless disregard for the truth — to prove libel. Trump has spoken about his desire to “open up those libel laws. So that when the New York Times writes a hit piece which is a total disgrace, or when The Washington Post . . . writes a hit piece, we can sue them and win money, instead of having no chance of winning because they’re totally protected.”

So there was Trump at what he would consider Hit Piece Central on Monday morning, a meeting with The Post’s editorial board and yours truly (“She kills me, this one,” Trump said. He didn’t mean I made him laugh.)

Pause here, to give Trump credit for being willing to meet with people who have mercilessly attacked him. Not everyone would do that. Listening to Trump, he sounded genuinely hurt by the notion that people like me could write such terrible things about him.

“I’ve had stories written about me — by your newspaper and by others — that are so false, that are written with such hatred — I’m not a bad person,” Trump said. “I’m running — I want to do something that’s good. It’s not an easy thing to do.”

Indeed, and how much easier if he could chill the speech of folks like us with the threat of libel suits. Our publisher, Frederick J. Ryan Jr., asked Trump what opening up, exactly, he had in mind.

For someone who envisions some serious tinkering with the First Amendment, Trump didn’t seem to have given it much thought. He cited “the Hulk Hogan thing,” although that was an invasion of privacy case, not a libel suit. “I’d have to get my lawyers in to tell you, but I would loosen them up,” he said of the New York Times v. Sullivan rules. “I think I would get a little bit away from malice without having to get too totally away.”

In Trump’s ideal world, a writer who unfairly maligns him should have an obligation to correct the record. “And if they don’t do a retraction, they should . . . have a form of a trial. I don’t want to impede free press, by the way. The last thing I would want to do is that.”

Except that Trump, having been on the other side, knows something about what defending a libel case can cost. What was striking in his discussion of the issue was how much of it seemed directed not at news reporters who get facts wrong (Trump famously sued an author who questioned his status as a billionaire) but at opinion writers like me, whose freedom to be biting, as Brennan so well understood, is at the core of the First Amendment.

“Whether or not a newspaper can survive a succession of such judgments, the pall of fear and timidity imposed upon those who would give voice to public criticism is an atmosphere in which the First Amendment freedoms cannot survive,” Brennan wrote.

Read Times v. Sullivan, Mr. Trump.

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