Trump Wants to Send the National Guard Into Chicago. Here’s What the Law Actually Says About That.

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On Tuesday, Donald Trump suggested that he was planning to send federal troops into Chicago^[2], even over the objections of local officials^[3]. The Department of Defense has announced that it has secured Naval Station Great Lakes^[4], near north Chicago, to be used as a command center for an “immigration blitz” in the coming days. Only a few hours earlier, a federal judge in California had blocked^[5] the administration from using the military to fight crime in that state.

The statutory and constitutional protections barring the president from using the military for domestic crime-fighting purposes are long-standing and complicated. Elizabeth “Liza” Goitein has been ringing alarm bells for a very long time about the dangers of allowing the military to do domestic police work. She’s senior director of the nonpartisan Brennan Center’s Liberty and National Security Program^[6]. On this week’s Amicus podcast^[7] she explained why the courts, the Congress, and the Constitution have constructed a web of constraints on a president’s authority to deploy the National Guard to fight crime, and explained why Trump’s proposal to simply “go in^[8]” to cities as he deems necessary is unlawful in myriad ways. Their conversation has been edited and condensed for clarity.

Dahlia Lithwick: Perhaps we should open with a bracing reminder of what it is the Framers of the Constitution worried about when it came to allowing the military to engage in domestic policing.

Liza Goitein: What we are seeing from this president is an assault on the core principle and tradition against using the military as a domestic police force. The reason for this principle in some ways is really obvious: If the president can turn the army inward against the people of this country, that can be an extremely powerful tool of oppression and tyranny. At a minimum, it creates a chilling effect on the willingness of the people of this country to speak out and to express dissent or disagreement with the policies of the person who’s commanding the soldiers who have been deployed into their streets. So this is fundamentally at odds with democracy and with individual freedom. That’s why we have this principle. That’s why we have this tradition.

Unfortunately, the law that enshrines this principle, the Posse Comitatus Act^[9], does have some loopholes in it, particularly when it comes to the National Guard, and particularly when it comes to the District of Columbia. And so what we’re seeing is that the president is trying to exploit these loopholes in a way that previous presidents haven’t done. Until now, despite its weaknesses, the Posse Comitatus Act has served as a very powerful norm, but Trump is now shredding that norm.

We keep talking about Posse Comitatus, so maybe it’s time to sketch out what it means?

The Posse Comitatus Act prohibits using the military as a Posse Comitatus. That’s not very helpful, right? That’s Latin. What it basically means is that the military can’t be used for law enforcement purposes. But it’s not always clear what is a law enforcement purpose and what isn’t a law enforcement purpose. And frankly, this administration has taken an incredibly crabbed view of what constitutes law enforcement being performed by troops. So we have to look at how the courts have interpreted this, and why the courts haven’t interpreted it that way.

What the courts have said is that any time the use of the military pervades civilian operations or when the military is used in a way that subjects civilians to an exercise of military power that is compulsory in nature—and really, if you look at this case law, the court was particularly concerned with face-to-face interactions between soldiers and civilians—that’s when you get that chilling effect. That’s when you get the potential for the military to be used in ways that constrain full participation in our democracy and can constrain the freedom to express dissent.

When you have these actions by the military that directly affect the liberties of civilians, that’s when you trigger the concerns that underlie the Posse Comitatus Act. As long as you have soldiers exercising this power over civilians to compel them to do certain things or not do certain things, that is when the Posse Comitatus Act is triggered, and that’s when we have those concerns.

So when I read that the National Guard can’t detain, but they can arrest; that they can’t search, but they can ask questions—the question is whether I feel as though they are doing domestic policing against me?

When a member of the National Guard who has been federalized, or a U.S. Marine, temporarily detains someone, the question is: Is that person free to go? And I don’t think anyone would say in these cases that that person is free to go. I don’t think these members of the military are saying, “If you would be so kind, why don’t you hang out here a minute? But if you have somewhere else to be, go ahead.” That’s not what’s happening. There is a compulsory power that’s being exercised when a person is temporarily detained.

I think we should map out the shape of the legal guardrails here. 

The first principle is that the president normally should not be using the military to engage in domestic law enforcement. That principle is enshrined in the Posse Comitatus Act, which prohibits federal forces from participating in law enforcement unless it has been expressly authorized by Congress or in the Constitution.

Now, if you read the Constitution, it actually doesn’t give any powers to the president to deploy the military for law enforcement. So really there aren’t any express exceptions in the Constitution, but Congress has enacted several. And the most potent by far is the Insurrection Act^[10]. That is the primary statutory exception to the Posse Comitatus Act.

But in addition to the Insurrection Act and the exceptions Congress has passed, there are also some loopholes and some gaps. And the main one is this general rule that the Posse Comitatus Act does not apply to the National Guard unless the National Guard has been called into federal service. And that is because the Posse Comitatus Act is primarily concerned with potential abuses of the military by the president. And because the National Guard, in every case except for Washington, D.C., is not under the president’s command and control unless it’s been called into federal service, the Posse Comitatus Act doesn’t apply if the Guard hasn’t been federalized.

So the president says he’s going to send the Guard into Chicago. Illinois Gov. J.B. Pritzker is saying “Hell no.” What is President Trump going to invoke in order to say that he doesn’t care what Gov. Pritzker says?

The president cannot replicate what he has done in D.C. in Illinois. He just couldn’t do that under the relevant legal authorities. In D.C., he was able to deploy the D.C. National Guard because he has command and control over the D.C. National Guard. And he was able to ask governors from other states to send their Guard forces into D.C. because D.C. is not a state. It is a federal territory. It would be very different in Illinois, where the president doesn’t have command and control of the Illinois National Guard as a default. And he could not ask governors to send their Guard forces into Illinois without the governor’s consent because under the Constitution, states are sovereign entities with respect to one another. So one state cannot invade another state, even if the president asks them to. As long as the Guard force remains, as a legal matter, under state command and control, then those Guard forces are state officers and they cannot enter another state without that state’s consent.

So if President Trump wants to deploy Guard forces in Illinois, he is going to have to federalize them. And that means he has to rely on a federal statute that authorizes federalization. There is no federal law that authorizes federalizing the National Guard for local crime control. It doesn’t exist, not even under the Insurrection Act, which is probably the broadest authority that a president has to deploy the military domestically. If the president wants to use the military to execute the law, it has to either be a federal law or it has to be a state law that protects the constitutional rights of a class of people. So basically, civil rights law. Those are the laws that the president can use the military to enforce under the Insurrection Act. Local crime is never going to be a basis for the president to federalize the National Guard and to deploy troops to enforce the law.

What Trump might do is change his tune once he gets into court and say that this is not about local crime, this is about enforcing immigration law, which is what he did in Los Angeles. In Los Angeles, he had the same constraints. He doesn’t control the California National Guard as a matter of default. He can’t ask governors of other states to send their Guard forces into California. So he had to federalize the Guard there. And he relied on a law, 10 U.S.C. 12406, that authorizes him to federalize the National Guard to execute federal law when necessary.

He might try to do something similar in Illinois, but the problem is there aren’t currently mass protests in Chicago against ICE raids. That was the pretext in California. So he’ll need another pretext. And it’s not clear what he would point to, or what he could point to. He might try to say that the fact that there are sanctuary city policies somehow interferes with the execution of federal law. The courts have heard challenges to these sanctuary policies. And one of the things that they have emphasized is that there is a distinction between what these policies do, which is withhold assistance from federal law enforcement, and actual obstruction of federal law. And sanctuary policies fall into the former category that is protected by the 10^th Amendment. Under the 10^th Amendment, the president cannot force or coerce states into using their local law enforcement or their resources to execute federal law or to assist with the execution of federal law that would violate the Constitution. So if the president tried to rely on that, he would run into some 10^th Amendment problems.

I’m not being Pollyanna about this. If President Trump wants to do this, he’ll try to find a legal hook and he will continue to try to push the boundaries of the law.

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