A federal appeals court blocked President Trump from using an 18th-century wartime law to quickly deport a group of Venezuelan migrants late Tuesday, rejecting the administration’s argument that they were part of an "invasion" of the United States. 

A three-judge panel of the US Court of Appeals for the Fifth Circuit said it did not find that the law, the Alien Enemies Act, applied in the case of these migrants, who are accused by the Trump administration of being members of Tren de Aragua, a violent gang with roots in Venezuela. In a 2-1 ruling, the court said that it found no "invasion or predatory incursion" by a foreign power. 

The case is seen as a test by both the government and the American Civil Liberties Union of how the courts would view Trump’s use of the Alien Enemies Act, a powerful wartime statute that is rarely invoked, to deport migrants.

Lee Gelernt, a lawyer who argued the case for the ACLU, stated that this was an enormous victory for the rule of law, which makes clear that the President cannot simply declare a military emergency and then invoke whatever powers he wants. 

In April, the Supreme Court temporarily blocked the Trump administration from deporting the Venezuelan migrants while suits challenging Trump’s use of wartime powers proceeded through the lower courts, including the case ruled on by the Fifth Circuit on Tuesday.

The Fifth Circuit judges said on Tuesday that their injunction applied only to the use of the Alien Enemies Act and would not prevent the government from using other lawful means to remove foreign terrorists from the United States.

Temporarily halting the controversial move by President Donald Trump, the US Supreme Court issued a dramatic late-night decision on April 19, blocking an attempt to use an archaic, obscure law to deport Venezuelan migrants without due process.

By invoking the Alien Enemies Act, an archaic statute previously used only during declared wars in 1812, World War I, and World War II, the Trump administration has been able to deport migrants to El Salvador based on unproven allegations of gang affiliation without granting them judicial review or formal criminal charges.