Opinion | The Supreme Court Ruled. Trump and the A.C.L.U. Both Claimed Victory. Huh?

The strangest thing happened last week.

The Supreme Court undermined the Trump administration’s deportation policy, and the Trump administration … celebrated. President Trump called the court’s decision “a great day for justice in America.”

Stephen Miller, a key architect of Trump’s deportation strategy, posted in all caps, “Alien Enemies Act now in full effect. The foreign terrorists will be arrested and expelled.” Kristi Noem, the secretary of homeland security, also celebrated the ruling, declaring on X, “President Trump was proven RIGHT once again! SCOTUS confirms our Commander-in-Chief Donald J. Trump has the power to stop the invasion of our country by terrorists using war time powers.”

At the same time, however, the American Civil Liberties Union and its allies also took a victory lap. Lee Gelernt, the lead counsel for the immigrant plaintiffs in the case and the deputy director of the A.C.L.U.’s Immigrants’ Rights Project said the case represented an important victory.

His co-counsel, Skye Perryman, the president and chief executive of Democracy Forward, said the court’s ruling “affirms what we have long known: the Trump administration acted unlawfully when it removed people from this nation with no process.”

This is all quite confusing. So, who is correct? The Trump administration or the A.C.L.U.?

The answer is the A.C.L.U., and it’s not close. The Trump administration won a narrow procedural victory, but it took a substantial constitutional loss.

The case, Trump v. J.G.G., challenged the Trump administration’s decision to invoke the Alien Enemies Act to allow it to summarily deport people it claimed were members of a violent Venezuelan gang called Tren de Aragua.

Trump does not need to invoke the Alien Enemies Act to deport any group of illegal immigrants. It’s not hard to deport illegal immigrants. In fact, the Department of Homeland Security deported an average of 352,000 people a year between the 2020 and 2024 fiscal years. But conventional deportation requires a legal process.

The Trump administration, however, doesn’t care much for due process. It wants maximum authority and maximum autonomy, and it reached for presidential war powers to grant it the ability to sweep people out of the country, at will.

The administration and its allies have been comparing illegal immigration to an invasion for years. They’ve been desperate to use the full powers of government, real or imagined, to stanch the flow of immigrants into the country and to facilitate mass deportations to expel those already here.

On Jan. 20, Trump issued a proclamation that declared an invasion at the southern border. On March 15, Trump went a step further and formally invoked the Alien Enemies Act against Tren de Aragua. The act grants the president extraordinary authority to deport citizens of a hostile nation in the event of a declared war or an “invasion or predatory incursion.” Immediately after Trump issued the proclamation, the administration — without a hint of due process — deported more than 200 people to a brutal prison in El Salvador.

Five detainees sued the administration in federal court in Washington D.C., and in March, Judge James Boasberg issued two temporary restraining orders that blocked the Trump administration from using the Alien Enemies Act to deport the plaintiffs in the case or to deport “all noncitizens in U.S. custody who are subject to” Trump’s order.

In a 5-4 decision, issued last Monday the Supreme Court vacated Judge Boasberg’s orders. That’s the reason Trump and his team celebrated. But they either didn’t read the ruling closely or they’re lying to the public. The Alien Enemies Act is not, as Stephen Miller claimed, “in full effect.”

In reality, the Supreme Court demolished Trump’s rationale for invoking the law.

In its decision, the court held that every detainee is entitled to due process before deportation under the Alien Enemies Act. Specifically, all detainees are not only entitled to file a habeas petition in Federal District Court challenging their status as a so-called alien enemy, they’re also entitled to challenge the “interpretation and constitutionality” of the Alien Enemies Act itself.

A habeas petition is a legal filing that challenges the grounds for detention. The right to file a habeas petition is a core constitutional right that applies to any person in American custody, not only American citizens. It’s long been the final legal firewall against arbitrary imprisonment. The Supreme Court ruled that detainees have to file their request in the district in which they are held, and since the detainees were not located in Washington D.C., they had brought their case in the wrong court.

As Justice Brett Kavanaugh wrote in his concurrence, the disagreement between the justices “is not over whether the detainees receive judicial review of their transfers — all nine members of the court agree that judicial review is available. The only question is where that judicial review should occur.”

Justice Sonia Sotomayor was emphatic about the meaning of the court’s ruling: “To the extent the government removes even one individual without affording him notice and a meaningful opportunity to file and pursue habeas relief, it does so in direct contravention of an edict by the United States Supreme Court.”

This means that the Trump administration cannot repeat the stunt it pulled in March. It cannot hustle detainees on a plane, fly them to El Salvador and then wash its hands of the matter by declaring that the detainees were now outside the jurisdiction of the court. An encore of that performance would directly defy the court.

In some ways, this ruling makes it harder to deport aliens under the Alien Enemies Act than would have been the case if the president had used conventional legal means. Every detainee is now entitled to his day in federal court, potentially flooding those courts with hundreds of petitions, each requiring individualized hearings with a right to appeal.

Each court also has the ability to declare the application of the Alien Enemies Act unconstitutional, thus beginning a legal process that could terminate Trump’s executive order once and for all.

From Trump’s perspective, that is not what winning looks like.

If there were any doubts about the meaning of the court’s decision, two different federal courts temporarily blocked any further deportations in their districts on Wednesday.

In Texas, Judge Fernando Rodriguez Jr., a Trump appointee, blocked the Trump administration from deporting any Venezuelans held at the El Valle detention center in Raymondville, Texas, until April 23.

In New York, Judge Alvin Hellerstein, a Clinton appointee, shielded Venezuelans in the Southern District from deportation without a hearing.

And then, on Thursday, the Supreme Court issued yet another immigration opinion. This time, it held (crucially, with no dissents) that lower courts had properly ordered the United States to facilitate the return of a man named Kilmar Armando Abrego Garcia.

Abrego Garcia was swept up in the administration’s dragnet and sent to El Salvador in defiance of a court order that explicitly prohibited his removal to that country because it would be dangerous for him to return.

The administration has been content to keep him in El Salvador, in inhumane conditions. In its brief to the Supreme Court, it argued that even if the administration had made an error, federal courts didn’t “license district courts to seize control over foreign relations” and compel the United States to bring him home.

Now, however, the Trump administration has to be “prepared to share what it can concerning the steps it has taken and the prospect of further steps” the court wrote, to bring Abrego Garcia back to America.

I don’t pretend that these Supreme Court rulings are a complete victory over a lawless Trump administration. Contesting the administration’s deportations will require a small army of lawyers to be ready to file hundreds (if not thousands) of habeas petitions. And we don’t yet know if the Trump administration’s invocation of the Alien Enemies Act was constitutional in the first place.

There is also still an open question regarding the fate of the hundreds of Venezuelans who were already removed to El Salvador without due process. Incredibly, on Wednesday, Noem said the detainees in El Salvador should stay in that prison “for the rest of their lives” — a grotesque violation of their human rights.

The administration would impose a life sentence in a foreign prison without any criminal conviction meriting the punishment. It’s hard to imagine a more cruel deprivation of due process.

The order in Abrego Garcia’s case gives me hope that the court won’t leave those Venezuelans behind. Some of the detainees may well deserve deportation and imprisonment. Some may not. After all, dozens of the detainees still have pending asylum claims in the United States. But that’s what due process is for — to separate the guilty from the innocent.

Even so, the absence of total victory for the constitutional order shouldn’t diminish the significance of the Supreme Court’s rulings. In a remarkable act of judicial jujitsu, the court engineered an outcome that Trump celebrated, even as it diminished his freedom of action.

It remains to be seen whether Trump will comply with the Supreme Court’s orders — or choose this moment to trigger a constitutional crisis. In fact, the administration has already filed a defiant document in Abrego Garcia’s case, claiming that it hasn’t had enough time to provide the district court with the information it demands. But regardless of what Trump does next, one thing is clear: The judicial branch of the American government still has a spine.