Back in 2010, 15-year-old Sergio Hernández was hanging out along the Mexican side of the Southern border with his friends, playing a game where they would touch a fence on the border and then run back. A Border Patrol agent on the U.S. side named Jesus Mesa saw them and, when Hernández ran again, shot and killed him in front of everyone in the middle of the day.

A civil suit was the only option for Hernández’s parents. The case, Hernández v. Mesa, wound up at the Supreme Court, because the Department of Justice refused to prosecute Mesa, and when the Mexican government charged the agent with murder, the United States refused to extradite him. But just last week, the court decided the parents couldn’t seek damages for their child’s death. This case may seem singular and specific, but it really isn’t—it’s part of a pattern at the Supreme Court that shows how the conservative majority is remaking immigration law, one ruling at a time.

On Monday’s episode of What Next, I spoke with Slate’s Mark Joseph Stern, who covers the Supreme Court, about why this case is such a big deal and what the consequences could be. Our conversation has been edited and condensed for clarity.

Mary Harris: The decision in the Mesa case rests on a precedent called Bivens. How would you explain that case to people who aren’t familiar with it?

Mark Joseph Stern: The full name of the case is Bivens v. Six Unknown Named Agents. This was a case where six narcotics agents committed horrible abuses against a source: broke into his house with no warrant and strip-searched him. And Bivens thought, That was definitely illegal, that was definitely unconstitutional, that was a huge Fourth Amendment violation.

But here’s the wrinkle: There is a federal law that guarantees you the right to sue a state law enforcement officer who violates your constitutional liberties, but there is no law that creates the same guarantee for federal law enforcement officers. If a state police officer abuses your constitutional rights, you can easily sue them under this statute. If a federal police officer violates your constitutional rights, it gets a lot trickier. And that’s where Bivens comes into play.

Bivens is the only thing that establishes the right for anyone to sue a federal law enforcement officer when they behave badly. But Bivens is a rule, not a law, so a judge can overturn it. Since the ’80s, conservative justices have seemed eager to do just that. What’s the argument against holding federal employees accountable when something goes wrong?

The argument, which I don’t agree with, is laid out pretty clearly by Justice Samuel Alito in his decision. The Constitution has a separation of powers: There is the legislative power that Congress gets to exercise and there’s the judicial power that the courts get to exercise. Alito says that when a court is figuring out how much money victims should get when Congress hasn’t said anything about it, the court is usurping legislative power.

There’s also another argument made by conservatives, which is that with great power comes not so much the responsibility, but the necessity to use it. And they don’t want to take away the power of these federal agents to be able to shoot first and ask questions later.

"Shouldn’t this be a straightforward example of a law enforcement officer going overboard?" — Mark Joseph Stern

That is tragically a persuasive argument at this Supreme Court: that federal agents need to make split-second decisions, that they need to be able to act quickly to protect the peace and protect lives. Sometimes they’ll make mistakes, and they shouldn’t be overly punished for those mistakes, because that comes with the territory. This court believes that about all law enforcement officers. So even when victims of police violence come to this court and are seeking justice for constitutional violations—even when Congress has allowed that to proceed—this court will often say, We’re not going to let you do that because we don’t want to tie the hands of law enforcement officers and make them afraid to use force when they really need to.

You were there for oral arguments for Mesa. Now that we have the decision, what do you think about how both sides presented their cases and how those arguments were received by the justices?

I think it was really clear during oral arguments how this case was going to come down, and that is because there was this massive gulf between the two different sides of the court.

For this family, this is not a difficult case. This is, in constitutional terms, an unreasonable seizure. This case involves a cross-border shooting, but the agent was standing on U.S. soil. He was a U.S. agent—he was vested with the power of the U.S. federal government. What the liberals were really asking was, why does it matter that the killing was at the border, that Mesa was an immigration officer? Shouldn’t this be a straightforward example of a law enforcement officer going overboard? This belongs in federal court and the victims deserve to have their say.

Justice Sonia Sotomayor was a major character in these oral arguments. She asked, why is it a problem that we hold this agent accountable?

She cited this amicus brief that was filed by former high-level officials at Customs and Border Protection who said, We used to work at CBP, and this agency has a huge problem. This agency is violent, lawless, and unaccountable. There is no discipline here. If you don’t let victims of CBP officers sue them in federal court, there will be no justice for the victims, because the U.S. government is never going to punish these officers. Sotomayor cited that and talked about how the agency has high rates of corruption and misconduct. Basically, the courts are the only ones who can step in and hold these people accountable. Nobody else is going to do it.

Sotomayor was saying that the play here is to make this agency accountable to no one.

Absolutely no one. There cannot even be a grieving parent of a victim coming into court and asking for modest damages. The agents are free to do whatever they want, anytime they want. No one’s going to punish them.

This massive gulf between the liberal and conservative justices during oral arguments, you can see it in the final decision the majority handed down. For the conservatives, Bivens now seems very far from sacred.

Justice Clarence Thomas and Justice Neil Gorsuch have now come out and said they want to overrule Bivens. John Roberts, Brett Kavanaugh, and Alito have not admitted that yet. But reading between the lines of this decision, I get the sense that what they’re saying is: We will let you have your Bivens claims, but if you try again to expand this, then we’re going to overturn this precedent because we’ve never liked it.

If we look at the immigration decisions that have come down to the Supreme Court over the past couple of weeks as a test for how this jurisprudence will move forward in the future, what do they tell us?

They suggest to us that Trump, being unleashed and unrestrained after impeachment, is going to have more victories at the Supreme Court. There’s all of this reporting suggesting that his advisers and Cabinet secretaries and lawyers don’t worry about legal challenges anymore. They now have total faith in the Supreme Court. It’s going to be a pretty frightening run, because if Trump wins in November and shores up that majority, then he will have captured another branch of government. And nobody’s going to step up to him and say, you’ve gone too far.

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