When President Donald Trump used federal officers—the Park Police and the National Guard—to viciously clear Lafayette Square of its peaceful Black Lives Matter protesters, many of us watched in horror. The scene was unimaginable in its ferocity, in the face of a peaceful assemblage in front of the White House. Across the political spectrum, we use the First Amendment rights to speech and assembly to pressure politicians to do what we believe they should.

Trump’s abusive acts were so dangerous to our democratic principles that his conservative former secretary of state, James Mattis, emerged from his self-imposed silence to warn the country of the constitutional concerns surrounding Trump’s use of the military in a crackdown on demonstrators. He wrote, “I swore an oath to support and defend the Constitution. Never did I dream that troops taking that same oath would be ordered under any circumstance to violate the constitutional rights of their fellow citizens—much less to provide a bizarre photo op for the elected commander-in-chief, with military leadership standing alongside.” This was no warning. It was a distress signal intended for all of us to hear, no matter our party or politics.

Mattis’s words should have served as a helpful fencing off of the White House and other senior cabinet officials to ensure they no longer left the corral designed by the Constitution to protect “we the people” from the tyranny of a national army, or a President with despotic designs. Instead, Trump tried to find a hole in that fencing that would help him and his henchmen, namely Bill Barr, sneak out of the constitutional corral and further insert federal officers to more brazenly violate our constitutional rights. The Administration used the law that allows federal law enforcement officers to protect federal property to crack down, seemingly randomly, on demonstrators. Trump sent U.S. Marshals, who are charged with protecting federal buildings, and also the Department of Homeland Security Border Patrol, who are not.

We saw video of two different protesters violently snatched off the street and into an unmarked van to be “questioned.” This prompted the U.S. Attorney for the District of Oregon to request an investigation by the DHS’s Inspector General and the Oregon Attorney General to file a lawsuit. In a separate incident, a former veteran who had never attended a demonstration went to the protest only to be hit with a baton and pepper sprayed for his mere presence. He said in later interviews that the federal officers appeared to be acting randomly. That is to say, the force was excessive.

It is important to acknowledge that there has been violence during some periods of protest. It is also important to note that federal officers do have federal law enforcement authority. But the Trump Administration can’t justify protection of federal property by randomly rounding up people simply for their presence at an assembly where some may have committed a crime. That would be like the police arresting everyone who lives on a city block where a bank robbery took place.

We should also differentiate federal officers deployed to take action in a city under an existing law on the one hand and, on the other, federal officers deployed to assert powers the President only wishes he had. We do have a federal law, the Insurrection Act, that presidents can use to send federal agents to protect the constitutional rights of ordinary people where local law enforcement will not. President Dwight Eisenhower sent the 101st Airborne to protect the nine Black students who were desegregating Little Rock, Arkansas’s Central High School in 1957 because the governor promised to deploy the National Guard to bar them from the building.

As Mattis so rightly stated in his public condemnation of Trump, “The words ‘Equal Justice Under Law’ are carved in the pediment of the United States Supreme Court. This is precisely what protesters are rightly demanding.” Trump’s actions simply defy the constitutional protections against a tyrannical commander-in-chief by turning troops on his own people and abrogating individual freedoms and liberties we hold sacrosanct. He does it to federalize the very police violence that so many Americans march to prevent. This, in turn, has meant that local police have, in some disturbing instances, become tyrannical mimics. If we don’t want police officers putting their knees on our necks, why would we want federal agents doing it?

New York City is one of the cities to which Trump has threatened to send federal officers and whose federal grants he has threatened to block because the city council took very modest steps to reduce the police budget and ban chokeholds. But New York Police officers have also been captured on video engaging in apparently random violence including batoning, pepper-spraying, and pushing to the ground Black Lives Matter demonstrators. To make matters even worse, after the viral videos in Portland, the nation witnessed the arrest of a young demonstrator on a skateboard in New York, yanked by plain-clothed officers in an unmarked car. It was, by then, a chillingly familiar scene. The New York Police Department later said that the protester was being arrested for vandalizing five police cameras.

Even more chilling was a five-hour police siege of the apartment of a Black Lives Matter protester for yelling in a bullhorn at a demonstration almost two months earlier. The two dozen, riot-geared police officers cordoned off the block. Police helicopters flew over the apartment building. And yet, they had no arrest warrant. It seems more than plausible that this undeniably authoritarian display by a local police force against a resident whose crime appeared to be using a bullhorn to complain about policing too loudly was unleashed by the example set by federal officers in Oregon.

Meanwhile, Trump calls mayors “weak” if they refrain from aggressive police tactics that crack down on people who have been demonstrating to denounce violent policing. His calls ignored the frightening videos and claims of protesters that the police themselves were instigating some violence. And not only in New York. Trump, according to the Mayor of Portland Ted Wheeler, incited more violence in Portland by sending federal troops.

Trump manipulates fear, frames problems in “us versus them” terms and then layers on a thick dose of “tough on crime” language to assert the need for his abusive authority. But this formulation can also frame for local police how they should understand, and feel victimized by, a world that increasingly tries to hold them to account. This means that Trump has not only made a mockery of our Constitution’s protections against tyranny by improperly inserting federal officers into local law enforcement, then inciting them to violate First and Fourth Amendment rights; he is also undermining a presidential norm to keep the peace, use the power of the office to protect the constitutional rights of people of color and of any resident where local law enforcement will not, and stoking fear and division that endanger our safety as well as our freedoms.