When federal District Judge Fernando Rodriguez Jr. ruled this month that the Trump administration could not swiftly deport migrants under a centuries-old law called the Alien Enemies Act, he looked to the past for guidance.
All the way back to the 1780s.
Along with his opinion, Rodriguez did his own research: He published an appendix of historical fact-finding, linking to dozens of examples of how the terms "invasion" and "predatory incursion" were used in correspondence by George Washington, Thomas Jefferson, James Madison and others in the years around 1798, when the Alien Enemies Act was signed into law.
"The historical record renders clear," Rodriguez concluded, that the Trump administration's use of the Alien Enemies Act "is contrary to the plain, ordinary meaning of the statute's terms."
Rodriguez, who was appointed to the bench by President Trump in 2018, is one of a handful of federal judges who've recently looked back to the first decades of U.S. history to define what constitutes an invasion. In the process, several have rejected one of the key legal arguments for the Trump administration's use of a wartime deportation authority.
Using the word "invasion" to describe illegal immigration has moved from the fringes to the mainstream of Republican politics in recent years. But that framing has not been fully tested in court until now.
The White House issued a proclamation in March declaring that Tren de Aragua, a Venezuelan criminal group that the administration has designated a foreign terrorist organization, is "conducting irregular warfare and undertaking hostile actions" against the U.S., and arguing that the gang is "closely aligned" with the Venezuelan government.
"The result is a hybrid criminal state that is perpetrating an invasion of and predatory incursion into the United States, and which poses a substantial danger," the proclamation says.
The U.S. intelligence community does not share the view that the Venezuelan government controls or is even directly connected to Tren de Aragua, according to a recently declassified memo. The Office of the Director of National Intelligence concluded that while some members of the Venezuelan regime may tolerate or work with Tren de Aragua, there's no evidence of widespread, organized cooperation.
Still, the Trump administration used that presidential proclamation to quickly deport more than 130 alleged members of Tren de Aragua to a Salvadoran prison by invoking the Alien Enemies Act. Those deportations are now at the heart of the legal fight over Trump's immigration crackdown and his efforts to limit due process for migrants.
Immigrant advocates including the American Civil Liberties Union challenged these deportations, arguing that the Trump administration has offered little evidence that the Venezuelans are gang members, and that the men have a right to contest those allegations in court.
Moreover, the ACLU argues, the Trump administration cannot use the wartime powers laid out in the Alien Enemies Act at all, because it was intended to counter military invasions and incursions, not as a response to illegal immigration or criminal gangs. And some judges are taking a similar view.
"The plain, ordinary meaning of 'invasion' was an entry into the nation's territory by a military force or an organized, armed force," Rodriguez wrote in his order on May 1, when he found the administration's use of the Alien Enemies Act "unlawful."
Rodriguez's ruling marked the first time a federal judge had reached a final decision on the Trump administration's use of the law, although it applies only in the Southern District of Texas. Federal judges in Colorado and the Southern District of New York issued similar decisions, granting preliminary injunctions in their respective districts.
But not all judges have reached the same conclusion. In Pennsylvania, federal judge Stephanie Haines ruled this week that the Trump administration can use the Alien Enemies Act to deport alleged gang members, as long as it gives them at least 21 days to contest their removal in court.
Judge Haines, too, looked back to the historical record. And she rejected the Trump administration's definitions of invasion and predatory incursion, finding that "migration alone" is not sufficient to invoke the Alien Enemies Act. But Haines, who was appointed by President Trump in 2019, ruled that a "hostile entry" into the U.S. by a foreign terrorist organization such as Tren de Aragua should count as a predatory incursion under the law.
"That definition is faithful to the meaning of 'predatory incursions' in 1798, but it also accounts for new applications given 'changes in the world,'" Haines wrote in her opinion.
So far, her ruling is an outlier. Most judges who've examined the historical record have ruled against the Trump administration.
"The term 'invasion' was well known to the Fifth Congress and the American public circa 1798," wrote Judge Karen Henderson, of the U.S. Court of Appeals for the District of Columbia Circuit, in March. "The phrase echoes throughout the Constitution ratified by the people just nine years before. And in every instance, it is used in a military sense," Henderson wrote in a concurring statement in another case challenging deportations under the Alien Enemies Act.
In court filings, Justice Department lawyers argued that Tren de Aragua is "clearly perpetrating an invasion or a predatory incursion into the United States. Although the definition of 'invasion' obviously encapsulates a military entry, the accepted definition of that term is far broader."
But Henderson, who was appointed to the appeals court by President George H.W. Bush, was not persuaded. "The text and its original meaning say otherwise," she wrote.
The Supreme Court has allowed the White House to continue to deport Venezuelans under the Alien Enemies Act, for now, with conditions. But the high court has yet to weigh in on the larger question of whether Tren de Aragua constitutes an "invasion" or military attack under the law.
The Alien Enemies Act had been previously invoked only three times in American history, all at times when the U.S. had officially declared war.
"I really saw the Alien Enemies law as a war power and as only to be implemented in times of declared war," said historian Terri Halperin, the author of The Alien and Sedition Acts of 1798: Testing the Constitution.
When the Alien Enemies Act was signed into law in 1798, the U.S. was locked in an undeclared naval war with France. At the time, Halperin says, Congress met for only a few months of the year, and lawmakers worried that the executive branch might need to respond quickly to a military strike on U.S. territory.
"Congress couldn't act quickly to declare war," Halperin said. "So by including 'invasion' or 'incursion' in the law, that was a way to sort of work around the long congressional recess."
The Trump administration argues that the Alien Enemies Act was intended to give the executive branch sweeping powers.
"The founding generation that wrote this law very clearly — these are the same people who wrote the Constitution — very clearly wanted to ensure the president had the broadest range of authority to remove from the nation noncitizens who are part of an alien enemy force," said Stephen Miller, the White House deputy chief of staff, in March. "That's the president operating at the absolute apex of his constitutional authority."
But historians say that this reading leaves out some crucial context.
The Alien Enemies Act is the only surviving statute from a set of four laws known as the Alien and Sedition Acts. The laws were deeply controversial at the time, historian Halperin says, as the young nation was still debating the powers of the presidency, along with the meaning of the Constitution and the First Amendment.
"That's not settled in the 1790s," Halperin said. "They're trying to figure it out in a world in which they're not quite sure that their independence as a nation is guaranteed or secure."
Another of these laws, known as the Alien Friends Act, did grant the president sweeping powers to detain and expel any alien he deemed "dangerous to the peace and safety of the United States," even without a declaration of war.
But it did not last long. The Alien Friends Act was widely criticized by James Madison and other Founders for depriving immigrants of due process and the right to a fair trial, and the new Congress allowed it to expire just two years after it was passed.
The Alien Friends Act was "enacted by narrow margins, widely derided as unconstitutional and allowed to lapse once the Federalists were swept from power in the elections of 1800," Judge Henderson wrote.
To some, the White House appears to be conflating the two laws.
"It seems to me that the Trump administration is using the Alien Enemies law like the Alien Friends law," said Halperin. The Alien Enemies Act, the less controversial of the two, managed to survive into the 21st century. Now the Trump administration is trying to revive the law — but is finding an increasingly skeptical judiciary in its way.
"The theme that rings true is that an invasion is a military affair," Henderson wrote, "not one of migration."
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