U.S. President Donald Trump at a rally in Kentucky in MarchJonathan Ernst / Reuters

I’ve had to look long and hard to find examples of presidential candidates who feared legal trouble because of speeches they made.

So far the list is Thomas Jefferson, Eugene V. Debs, and Donald J. Trump. Of these three, only one—the current president—might actually be held legally responsible for incitement to violence.

Trump may in fact have violated the law even after a century of First Amendment evolution designed to protect political speakers and their speech.

Jefferson never actually ran afoul of the Sedition Act of 1798, but as written, it held a clever trap for him. He was, by the bizarre workings of the Electoral College, vice president under his great foe, President John Adams. Adams’s allies jammed through Congress a law providing prison for anyone who uttered “false, scandalous and malicious writing or writings against the government of the United States, or either House of the Congress of the United States, or the President of the United States, with intent to defame  ... or to bring them, or either of them, into contempt or disrepute; or to excite against them ...  the hatred of the good people of the United States.”

Makes it hard to run against an incumbent and his party, yes? The law did not outlaw criticism of the vice president, so the pro-Adams forces were free to go on attacking Jefferson as an atheistic pro-French anti-Christ without fear of legal redress.

Federal prosecutors never actually went after Jefferson, despite partisan accusations of treason, and soon public opinion turned against the Sedition Act and its Federalist sponsors.

Debs, the head of the American Socialist Party, received 900,000 votes for President in 1912. On June 16, 1918, speaking to a Socialist gathering in Canton, Ohio, he expressed sympathy for Rose Pastor Stokes, a prominent Socialist who had been sentenced to 30 years in prison for criticizing the war. “I want to admit without reservation that if Rose Pastor Stokes is guilty of crime, so am I,” Debs said. The government took him at his word, and Debs was sentenced to ten years, a sentence cheerfully affirmed in a brusque opinion by Justice Oliver Wendell Holmes Jr.

In 1920, Debs ran for president from his cell and received 919,000 votes—more than he had as a free man. In 1921, President Warren Harding commuted his sentence.

Now to the present: here are the words that have gotten our current leader in trouble: “Get ‘em out of here!”

Trump uttered this deathless phrase from a speaker’s platform in Louisville, Kentucky, on March 1, 2016, during one of his mass rallies. Members of the crowd began shoving and hitting a group of protesters. He also said, “Don’t hurt ‘em. If I say ‘go get ‘em,’ I get in trouble with the press.”

The protesters filed suit against Trump, the Trump campaign, and the alleged assailants in federal district court in Kentucky. The lawsuit seeks money damages; among other things, they claim Trump’s speech was “incitement to riot.”

On Friday, Judge David J. Hale ruled that they had made out a genuine claim against the President.

To be clear: Judge Hale did not decide that Trump actually “incited” a riot. But he did rule that, if the protesters’ version of the facts is proved at trial, candidate Trump did just that.

It’s hornbook law that the First Amendment does not cover “incitement” to violence. But over the years, the United States Supreme Court has devised a definition of that term that makes it almost impossible to punish anyone for the offense.

The current test comes out of a 1969 case called Brandenburg v. Ohio. In 1964, an Ohio Klansman named Clarence Brandenburg held a “rally” on a private farm—attended by about 12 fellow Klansmen—and invited a camera crew from a local TV station. They donned robes, burned a cross, sang a Klan song, and then heard a largely incoherent address by Brandenburg, who said, “We're not a revengent organization, but if our President, our Congress, our Supreme Court, continues to suppress the white, Caucasian race, it's possible that there might have to be some revengeance taken.” Brandenburg was convicted of violating an Ohio state law that banned “advocat[ing] ... the duty, necessity, or propriety of crime, sabotage, violence, or unlawful methods of terrorism as a means of accomplishing industrial or political reform.”

The Supreme Court that heard the case knew that America in the late 1960s was as volatile as the steam boiler in Stephen King’s The Shining. Southern white governments were trying to silence Civil Rights advocates, while campuses were boiling with student opposition to the war in Vietnam. Feminist advocates had held the first “speak out” about reproductive rights, and others had picketed the Miss America pageant in 1968. Latino students in Los Angeles were staging walkouts from public high schools. The Stonewall Riot, which launched the LGBT movement, was only weeks away.

Free speech was heading for crisis, and the Justices used Brandenburg to signal that they would not tolerate the use of “incitement” as an excuse to shut down political discussion.

The First Amendment, the Brandenburg majority wrote, protected even speech that urged breaking the law—unless it was “directed to inciting or producing imminent lawless action and is likely to incite or produce such action.”

This short phrase is haymaker to any prosecution for “incitement.” “Directed to” means that the speaker must have intended to cause violence; “likely to” means that there must be a true danger of violence; and “imminent” means that the danger must exist at the moment of the speech—not days, hours, or possibly even minutes afterwards.

In Nwanguma v. Trump, the Louisville case, Judge Hale found it “plausible” that “’get ‘em out of here’ advocated the use of force.” In part, that’s because “it is stated in the imperative; it was an order, an instruction, a command.” Violence was certainly “likely,” the court wrote—in fact, it actually occurred. The plaintiffs may be able to prove intent from the circumstances surrounding the speech, he added.

The case against Trump and his campaign has a long way to go. The plaintiffs will have to prove their charges to a jury, which might conclude that “get ‘em out of here” was just big talk, not “incitement.” But Judge Hale’s decision serves as a useful caution in two ways. First, it reminds us all that words are not always harmless. In a country as divided and tense as this one, we should all choose words carefully. Angry and sharp protest is one thing; “get ‘em out of here” or “knock the crap out of them” are something else.

Second, it sheds light on the words our president chooses. Listening to a characteristic Trump word salad, it is tempting to conclude that he simply blunders about, treating the English language, as Evelyn Waugh once wrote of Stephen Spender, the way a chimpanzee might handle a Sevres vase.

But in fact, Trump’s words sometimes seem to reflect more care than one might think at first. This is a man who has not flinched at calling for violence, torture, hatred and division; indeed, even the violent incidents at Louisville did not persuade him to moderate his tone. Neither did an incident a week later in Fayetteville, N.C., where Trump repeated his theme when confronted by protesters: “See, in the good old days this didn’t use to happen, because they used to treat them very rough.” Shortly afterwards, a supporter attacked a protester, leading eventually to the assailant’s arrest and to an actual investigation of whether Trump had committed a crime.

Trump and his supporters like to say that those who complain about him and his rhetoric are oversensitive “snowflakes.” At the same time, he complains bitterly about any verbal criticism, no matter how far away it is uttered or how decorous its tone. “Change libel laws?” he tweeted recently after complaining—for all the world like a sulky tweener in a YA novel—that the New York Times had “gotten me wrong.”

No matter how generous the limits on his speech, he seems determined to exceed them, while threatening anyone who speaks against him. I don’t know what a Kentucky jury will find, but it would not surprise this snowflake if Trump became the first sitting president to be found liable for incitement to riot.

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