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Yet Another Federal Court Rules Against Trump in an Alien Enemies Act Case
The Southern District of New York rules Trump invoked the Act illegally, because there is no "invasion" or "predatory incursion."
Another day, another federal court ruling against Trump in an Alien Enemies Act case. The Alien Enemies Act of 1798 (AEA) can only be used to detain and deport immigrants in the event of a declared war, or an "invasion" or "predatory incursion" perpetrated by a "foreign nation or government." The Trump Administration has been trying to use the AEA as a tool to deport Venezuelan migrants without due process, by claiming they are members of the Tren de Aragua drug gang. Today, Judge Alvin Hellerstein of the Southern District of New York issued a decision ruling that Trump's invocation of the AEA is illegal. It follows similar rulings by district courts in Texas and Colorado, and by Judge Karen LeCraft Henderson of the D.C. Circuit. Multiple earlier court decisions have reached the same conclusion with respect to the meaning of "invasion" in the Constitution.
Like previous AEA decisions, Judge Hellerstein ruled against Trump because there is no "invasion" or "predatory incursion":
A statute should be interpreted as to its plain meaning at the time of its adoption, in the context of the events of that time….
In 1798, the United States was engaged in an undeclared war with France. See David McCullough, John Adams, at 499-505 (2001). Their respective navies fought each other at sea. Id. at 499. The American government feared incursions by the French in the territories west of the Appalachian Mountains….
An "invasion," as used in the AEA, was understood as a "[h]ostile entrance upon the right or possessions of another" or a "hostile encroachment," such as when "William the Conqueror invaded England." Samuel Johnson, Invasion, A Dictionary of the English Language (4th ed. 1773). Another dictionary defined "invasion" as a "hostile entrance into the possession of another; particularly the entrance of a hostile army into a country for the purpose of conquest or plunder, or the attack of a military force." Noah Webster, Invasion, American Dictionary of the English Language (1828). The Constitution itself uses the term "invasion" on three occasions, all of which occur within the context of military action by a foreign state against the territorial integrity of the United States. Specifically, Section 8 of Article I of the Constitution provides Congress with the power to "call[] forth the Militia to execute the Laws of the Union, suppress Insurrections and repel Invasion," Section 9 of Article I, also known as the "Suspension Clause," bars the suspension of the habeas writ, "unless when in Cases of Rebellion or Invasion the public Safety may require it," and Section 4 of Article IV, also known as the "Invasion Clause," provides that the federal government "shall protect [the states] against Invasion…."
In a similar vein, an "incursion" was understood to mean an "[a]ttack" or "[i]nvasion without conquest." Samuel Johnson, Incursion, A Dictionary of the English Language (4th ed. 1773). And early cases used the term "predatory incursion" to refer to military-like conflicts waged by an Indian tribe or a foreign nation-state, as opposed to civil immigration violations. See, e.g., Huidekoper's Lessee v. Douglass, 7 U.S. 1, 7 (1805) (referring to a measure intended to "repel the predatory incursions of the Indians" as an antidote to an Indian war)….
I would put less emphasis on dictionary definitions and more on the use of these terms, in context, in the AEA and the Constitution. But Judge Hellerstein is right about the bottom line, here. I have defended the view that "invasion" requires a military attack, in more detail in my previous writings on the meaning of the term in the AEA and the Constitution.
Like earlier AEA rulings, Judge Hellerstein also rejected the claim that the invocation of the statute is a "political question" not subject to judicial review. He also ruled the administration illegally denied migrants detained under the statute due process and certified a class action challenging their deportation:
This nation was founded on the "self-evident" truths "that all men are created equal, that they are endowed by their Creator with certain unalienable Rights, [and] that among these are Life, Liberty and the pursuit of Happiness." Declaration of Independence, at ¶ 2 (1776). Our Constitution embodies these truths, in a limited government of enumerated powers, in its system of checks and balances separating the executive, legislative and judicial branches, and in its guarantee that neither citizen nor alien be "deprived of life, liberty, or property, without due process of law." U.S. Const. amend. V; see Plyler v. Doe, 457 U.S. 202, 210-12 (1982) (extending these protections to aliens).
Yet, in March 2025, more than 200 aliens were removed from this country to El Salvador's Terrorism Confinement Center ("CECOT"), with faint hope of process or return. The sweep for removal is ongoing, extending to the litigants in this case and others, thwarted only by order of this and other federal courts. The destination, El Salvador, a country paid to take our aliens, is neither the country from which the aliens came, nor to which they wish to be removed. But they are taken there, and there to remain, indefinitely, in a notoriously evil jail, unable to communicate with counsel, family or friends….
The Court grants Petitioners' motion for a preliminary injunction against removal. This Opinion gives the reasons. It discusses the whole of the AEA, and shows that the Presidential Proclamation, in mandating removal without due process, contradicts the AEA. The Opinion goes on to discuss the requirements of notice and hearing under both the AEA and the Constitution.
I have previously explained why Trump's AEA deportations violate the Due Process Clause of the Fifth Amendment.
Litigation over these issues will continue. But, as I noted last week, there is a growing judicial consensus that Trump's invocation of the AEA is illegal, covering both conservative and liberal judges.
