WASHINGTON – A federal judge Saturday blocked President Donald Trump from using the Alien Enemies Act to immediately deport members of the Venezuelan gang Tren de Aragua, ordering any deportation flights underway as a result of Trump invoking the 1798 law return to the United States.

The order came after Trump on Saturday issued a proclamation, which he signed the day before, that relies on the 18th-century law to deport members of the Tren de Aragua gang, which he said “continues to engage in mass illegal migration to the United States to further its objectives of harming United States citizens.”

The Alien Enemies allows the deportation without a hearing of anyone from the designated enemy country who is not a naturalized citizen. The law has only been invoked three times while the country was at war, to hasten the removal of citizens of enemy countries.

Hours before the proclamation’s release, Chief U.S. District Judge James Boasberg in Washington, D.C., granted a temporary restraining order Saturday and ordered the government not to deport five Venezuelan nationals cited in a lawsuit brought by two nonprofits, Democracy Forward and the American Civil Liberties Union.

During a subsequent hearing Saturday evening, the judge turned the lawsuit into a class action and extended the temporary restraining order to all non-citizens in the U.S. covered in Trump’s invocation of the Alien Enemies Act. An additional hearing is scheduled for Monday.

Despite the judge’s order, White House press secretary Karoline Leavitt said in a statement Sunday that nearly 300 alleged Tren De Aragua gang members were arrested over the weekend at Trump’s direction and had already been deported to El Salvador.

“Thanks to the great work of the Department of State, these heinous monsters were extracted and removed to El Salvador where they will no longer be able to pose any threat to the American People,” Leavitt said.

Secretary of State Marco Rubio also said in a statement Sunday that “hundreds of violent criminals were sent out of our country,” thanking President Nayib Bukele of El Salvador and saying he “volunteered to imprison” the migrants.

The temporary restraining order is for at least 14 days to allow litigation in the case to proceed.

In invoking the act, Trump’s proclamation said Tren de Aragua ‒ which Trump last month designated as a foreign terrorist organization ‒ has been “undertaking hostile actions and conducting irregular warfare against the territory of the United States both directly and at the direction” of Venezuela President Nicolás Maduro’s regime.

But Boasberg, an appointee of former President Barack Obama, said the Alien Enemies Act does not “provide a basis for the president’s proclamation given that the terms invasion, predatory incursion really relate to hostile acts perpetrated by any nation and commensurate to war.”

The Trump administration signaled it plans to appeal the restraining order.

Skye Perryman, CEO of Democracy Forward, an advocacy group representing the five Venezuelans, applauded the judge’s decision in a statement.

“Yet again, the judicial system is working to protect our democracy,” he said. “We are gratified to see the judge’s decision and will work on the next stages to ensure those impacted by this dangerous move to invoke war time powers when the nation is not at war — and has not been invaded – are protected.”

Trump has repeatedly described Mexican drug cartels and Venezuelan criminal gangs in war-like terms, such as

protecting against an “invasion.” He has already declared cartels and the Tren de Aragua gang terrorists. He campaigned on invoking the Alien Enemies Act and mentioned it again during his inauguration.

The Venezuelans, who are identified only by their initials in the lawsuit, fear the order will label their arrival an “invasion” or “predatory incursion” by a “foreign nation or government” because Trump has designated Tren de Aragua, a Venezuelan gang, as a foreign terrorist organization that might be deemed akin to a foreign nation or government.

The five Venezuelans fear deportation because they are already jailed based on immigration issues and are suspected members of Tren de Aragua, which they deny. They worry they will be deported as quickly as this weekend.

For example, one man in a Texas jail has tattoos but denies being a member of the gang. He fears being killed by Venezuelan police if he is returned to that country and has a pending asylum application.

What is the Alien Enemies Act?

Congress approved the Alien Enemies Act in anticipation of another war against the United Kingdom. It has been invoked three times: during the War of 1812, World War I and World War II, according to Katherine Yon Ebright, a counsel at the Brennan Center for Justice at New York University.

The law says a president can invoke it during “a declared war” with a foreign nation or government, or when “any invasion or predatory incursion is perpetrated, attempted or threatened” against the United States.

If invoked, the foreign citizen could “be apprehended, restrained, secured, and removed as alien enemies.”

Supreme Court upheld extending Alien Enemies Act beyond end of war

Despite being invoked during wars, former Presidents Woodrow Wilson and Harry Truman each continued to enforce the law after the end of hostilities, Ebright said. Wilson used it to detain German and Austro-Hungarian immigrants for two years after the end of World War I in 1918. Truman used it for detentions and deportations for six years after the end of World War II in 1945.

The Supreme Court upheld Truman’s extension in 1948 by reasoning the end of wartime authorities is a “political” matter.

“It is not for us to question a belief by the President that enemy aliens who were justifiably deemed fit subjects for internment during active hostilities do not lose their potency for mischief during the period of confusion and conflict which is characteristic of a state of war even when the guns are silent but the peace of Peace has not come,” Justice Felix Frankfurter wrote in the 5-4 decision. “These are matters of political judgment for which judges have neither technical competence nor official responsibility.”

This story has been updated to add new information.

Contributing: Reuters

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