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When the president advocates for a viewpoint or course of action, he does not do so merely as an influential public figure with millions of Twitter followers. He does it as the country’s chief executive, charged not only with ensuring that the law is followed but also with the more basic task of saying what the law is. This is the legal reality at the heart of the struggle over President Donald Trump’s recent promises to crack down on protesters in more than 30 cities nationwide who have taken to the streets to decry last week’s brutal police killing of George Floyd in Minneapolis. Presidential speech is never just speech. Because law enforcement begins with the simple act of legal interpretation, presidential speech is presidential action.

This is not how Americans usually think about what the president is doing when he speaks. Under the government’s three-branch structure, interpretation of the law is a function usually attributed to the courts. That’s because when it comes to defining the law’s parameters in the context of a specific dispute, the courts get the last word. As tensions explode across the country, however, America is getting an indelible reminder that, as the authority charged with overseeing the execution of the law, the president gets the first word.

The distinct significance of Trump’s words is likely to be more and more obscured as his administration escalates its operational response to the protests. This principle achieved surreal cinematic precision on Monday during Trump’s first public remarks on the protests from the Rose Garden. While Trump threatened to send the military into cities and states that fail to establish order, officers across the street shot tear gas and rubber bullets at peaceful protesters gathered near Lafayette Square, in an apparent effort to clear the area for the president’s photo op in front of St. John’s Church.

Yet as the escalation continues—as Customs and Border Patrol officers flood D.C., and the Pentagon prepares U.S. military troops for possible deployment to Minneapolis—Trump’s words continue to matter. These include the dozens of tweets he has issued in the past few days, promising to bring the full weight of the federal government down on protesters. Trump’s tweets are, on their face, clear interpretive acts. They are designed to affect, in real time, the definition of law and order meted out in the streets.

First, on Thursday, Trump tweeted, “When the looting starts, the shooting starts.” The suggestion was clear: Damage to property might well be met with deadly force. He walked back the comment but then doubled down when he retweeted Sunday, “This isn’t going to stop until the good guys are willing to use overwhelming force against the bad guys.” These tweets contain what lawyers would call proportionality and necessity assessments about what kind of government response is warranted against the protesters. The notion that property crimes warrant violence against human beings is the rot at the root of much police violence: The officer who crushed George Floyd’s neck until he died did so after Floyd allegedly attempted to buy cigarettes with a counterfeit $20 bill. But with thousands of police officers and protesters now clashing in the streets, Trump’s statements are all the more significant because the parameters of lawful use of force promulgated by the country’s 18,000-plus police departments are notoriously variable, inexact, and subjective. A 2018 report by the U.S. Commission on Civil Rights explains that “quantifying the appropriate amount of force in a given situation can be difficult and debatable.” Trump’s statements on how protesters should be treated could be used to fill in the gap.

Second, Trump’s tweets purport to identify the culprits responsible for the violence. On Saturday, Trump tweeted, “It’s ANTIFA and the Radical Left. Don’t lay the blame on others!” He went further, assessing the motives of the alleged perpetrators and explicitly concluding that their cause—the protest of the unlawful killing of George Floyd—is a pretext: “The professionally managed so-called ‘protesters’ at the White House had little to do with the memory of George Floyd. They were just there to cause trouble.” And he explained how the pretextual protests should be handled with a retweet proclaiming that “the radical-left formally divorced itself from America last night,” labeling the protesters “domestic terrorists and enemies of the United States,” and declaring that “they should be treated as such.”

Third, the president accused another group of unlawfully aiding the protesters: He tweeted, “The Lamestream Media is doing everything within their power to foment hatred and anarchy,” describing them as “truly bad people with a sick agenda.” Trump made these pronouncements even as videos emerged of police targeting journalists and media crews covering the protests, deploying tear gas and rubber bullets. David Kaye, the UN special rapporteur on freedom of expression, condemned the “appalling” attacks and criticized Trump for contributing to “an environment ready for such abuse.”

Fourth, Trump has tweeted ultimatums to cities and states, urging mayors and governors to “get tough” and “do more to restore order,” calling out Minneapolis Mayor Jacob Frey for allegedly falling down on the job, and threatening to send the U.S. military to “step in and do what has to be done.” His statements culminated in a phone call on Monday with state governors during which he berated them for being “weak,” encouraged the deployment of more aggressive tactics, and repeatedly demanded arrests and prosecutions.

The natural inclination is to draw a distinction between the president’s speech and the president’s actions—to separate the chaff from the wheat, the empty pronouncement from the concrete government response. For instance, when President Trump tweeted Sunday that “the United States of America will be designating ANTIFA as a Terrorist Organization,” journalists and legal experts moved to clarify why he lacks the legal capacity to do that. As Maggie Haberman and Charlie Savage have explained in The New York Times, “antifa” is not an organization but a loosely defined left-wing movement. And the U.S. has no domestic terrorism law to speak of; only foreign entities can be deemed terrorist organizations under existing federal law.

That the president is wrong about the law, however, doesn’t render his speech empty of legal import. Haberman and Savage’s analysis concludes it is “not clear that Mr. Trump’s declaration would have any real meaning beyond his characteristic attempts to stir a culture-war controversy, attract attention and please his conservative base.” But Trump’s tweets are imbued with “real meaning” by virtue of his office and how people in positions of legal authority understand that office.

This is obvious enough from the standpoint of formal government machinery. A flank of political appointees at the helm of federal government agencies stands ready to address the intent behind the president’s stated goals. Attorney General William P. Barr, for instance, followed up Trump’s “antifa” tweet by issuing a written statement calling out protester violence as the work of domestic terrorists and declaring that the FBI would partner with state and local police to identify them.

As commander in chief of the country’s armed forces, too, the president has the firepower to back up his opinions on civil unrest and has proved willing to use it. Last Thursday, when Trump began urging states to activate the National Guard, he was arguably engaging in a persuasive exercise that drew on state governors’ authority to call on their respective Guard forces, as well as his own authority to pay for their deployment, under Title 32. But when he threatened to send in the troops himself, he was pressuring state governors to bring about his desired result by explicitly referencing his power to place the National Guard under federal control through Title 10.

All of this is important, but so is the fact that, machinery aside, many of Trump’s statements are self-executing. Therein lies their power. Never mind what the courts say tomorrow; he speaks the law as it is understood and applied today. These statements might not be issued as part of an intelligible government policy, yet they are units of action with real consequences for how, among other things, uniformed officers decide to comport themselves amid the crowds. No, the specificity of the terminology and data used to analyze the effects of the Trump administration’s affirmative-policy moves—for example, its termination of Obama-era civil-rights investigations and its withdrawal of federal oversight from police departments in places including Ferguson and Baltimore—can’t be replicated in discussions about the propriety of Trump’s tweets. But when it comes to executive authority, vagueness doesn’t equal impotence. On the contrary, the nation is witnessing, firsthand, the immense might the president wields by way of his most ill-defined, hard-to-measure power: presidential speech.

This story is part of the project “The Battle for the Constitution,” in partnership with the National Constitution Center.

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