President Donald Trump speaks during an event about the relocation of U.S. Space Command headquarters from Colorado to Alabama in the Oval Office of the White House, Tuesday, Sept. 2, 2025, in Washington. Associated Press

WASHINGTON — A federal appeals court panel has ruled that President Donald Trump cannot use an 18th-century wartime law to speed the deportations of people his administration accuses of being in a Venezuelan gang. The decision blocking an administration priority is destined for a showdown at the U.S. Supreme Court.

Two judges on a three-judge panel of the 5th U.S. Circuit Court of Appeals, in the ruling Tuesday, agreed with immigrant rights lawyers and lower court judges who argued the Alien Enemies Act of 1798 was not intended to be used against gangs such as Tren de Aragua, which the Republican president had targeted in March.

Lee Gelernt, who argued the case for the ACLU, said the administration’s use of “a wartime statute during peacetime to regulate immigration was rightly shut down by the court. This is a critically important decision reining in the administration’s view that it can simply declare an emergency without any oversight by the courts.”

Abigail Jackson, a White House spokeswoman, said the majority erred in second-guessing the president.

“The authority to conduct national security operations in defense of the United States and to remove terrorists from the United States rests solely with the President,” Jackson said. “We expect to be vindicated on the merits in this case.”

The administration deported people designated as Tren de Aragua members to a notorious prison in El Salvador and argued that American courts could not order them freed.

In a deal announced in July, more than 250 of the deported migrants returned to Venezuela.

The Alien Enemies Act was only used three times before in U.S. history, all during declared wars — in the War of 1812 and the two world wars.

The administration unsuccessfully argued that courts cannot second-guess the president’s determination that Tren de Aragua was connected to Venezuela’s government and represented a danger to the United States, meriting use of the act.

In a 2-1 ruling, the judges said they granted the preliminary injunction sought by the plaintiffs because they “found no invasion or predatory incursion” in this case.

The decision bars deportations from Texas, Louisiana and Mississippi. In the majority were U.S. Circuit Judges Leslie Southwick, who was nominated by Republican President George W. Bush, and Irma Carrillo Ramirez, who was nominated by Democratic President Joe Biden. Andrew Oldham, a Trump nominee, dissented.

The majority opinion said Trump’s allegations about Tren de Aragua did not meet the historical levels of national conflict that Congress intended for the act.

“A country’s encouraging its residents and citizens to enter this country illegally is not the modern-day equivalent of sending an armed, organized force to occupy, to disrupt, or to otherwise harm the United States,” the judges wrote.

In a lengthy dissent, Oldham complained his two colleagues were second-guessing Trump’s conduct of foreign affairs and national security, realms where courts usually give the president great deference.

“The majority’s approach to this case is not only unprecedented — it is contrary to more than 200 years of precedent,” Oldham wrote.

The panel did grant the Trump administration one legal victory, finding the procedures it uses to advise detainees under the Alien Enemies Act of their legal rights were appropriate.

The ruling can be appealed to the full 5th Circuit or directly to the Supreme Court, which is likely to make the ultimate decision on the issue.

The Supreme Court has already gotten involved twice before in the tangled history of the Trump administration's use of the AEA. In the initial weeks after Trump's March declaration, the court ruled that the administration could deport people under the act, but unanimously found that those targeted needed to be given a reasonable chance to argue their case before judges in the areas where they were held.

Then, as the administration moved to rapidly deport more Venezuelans from Texas, the high court stepped in again with an unusual, post-midnight ruling that they couldn't do so until the 5th Circuit decided whether the administration was providing adequate notice to the immigrants and could weigh in on the broader legal issues of the case. The high court has yet to address whether a gang can be cited as an alien enemy under the AEA.