The Volokh Conspiracy

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Texas is Wrong to Equate Immigration and Drug Smuggling with "Invasion"

The argument is contrary to the text and original meaning of the Constitution, goes aginst precedent, and would have absurd consequences if accepted by courts.


What a real invasion looks like. Russian armored vehicle in Ukraine. March 2022.


The federal government is suing the state of Texas for installing floating buoy barriers in the Rio Grande River, thereby creating a safety hazard and potentially impeding navigation. The claimed purpose of the buoys is to prevent undocumented migration and drug smuggling across the US-Mexican border. The Biden Administration argues Texas's action violates the federal Rivers and Harbors Act, which restricts placement of barriers in navigable waters.

As Josh Blackman notes, Texas' brief in response to the lawsuit makes various statutory arguments, but also cites one of the "invasion" provisions of the Constitution as justification for the state's actions. Texas relies on Article I, § 10, cl. 3 of the Constitution, which provides, "[n]o state shall, without the Consent of Congress, . . . engage in war, unless actually invaded, or in such imminent Danger as will not admit of delay." Texas contends that illegal migration and drug smuggling qualify as "invasion," and therefore the Constitution gives the state the power to take military action in response, including placing buoys that would otherwise violate federal law.

Equating immigration and drug smuggling with "invasion" is not a new idea. It has long been advanced by immigration restrictionists as a legal justification for both federal and state measures against migration. I recently criticized these kinds of theories here:

[S]ome have argued that the Guarantee Clause of the Constitution, gives state and federal governments the authority to use military force to block such migration. The  Clause states that "The United States shall guarantee to every State in this Union a Republican Form of Government, and shall protect each of them against Invasion; and on Application of the Legislature, or of the Executive (when the Legislature cannot be convened) against domestic Violence…."

As a matter of logic and common sense, the equation of illegal migration and invasion makes little sense. Invasion involves large-scale use of force (or at least threat of force) to seize territory. Russia's attack on Ukraine is an invasion. Migrants crossing a border in search of freedom and opportunity are not….

The text of the Guarantee Clause suggests that it refers to violent attack. "Invasion" is paired with "domestic Violence" (which here obviously means uprisings against the state government, not the modern use of the term to denote violence in family and intimate relationships). [Andrew] Hyman also cites the provision of the Constitution indicating that "No State shall, without the Consent of Congress … engage in War, unless actually invaded, or in such imminent Danger as will not admit of delay." But the "invasion" referred to here is pretty obviously an armed attack. Otherwise, it would not make sense to "engage in War" as a response to it. I think it obvious that the "war" referred to here is a literal war against a foreign power, not a metaphorical war, such as the War on Drugs or the War on Poverty. This Clause is an exception to the constitutional requirement that only Congress has the power to declare war….

It might be argued that any illegal movement from one place to another qualifies as an "invasion." By that standard, however, an invasion occurs anytime someone smuggles in contraband, violates tariff regulations, and so on. In the pre-Civil War era, some states, such as Indiana, enacted laws banning the in-migration of free blacks from other states [as explained elsewhere in my earlier post, the Clause applies to interstate, as well as international invasions]. But it would be absurd to claim that black migrants who violated these laws were thereby "invading."

Similarly, one can argue that an "invasion" occurs anytime at least some migrants engage in violence…. But by that standard, one state has "invaded" another anytime criminals cross a state border to engage in any violent action. A real "invasion" requires a large-scale attack on the territorial or political authority of the state. Small-scale, nonpolitical private violence doesn't qualify.

It's worth emphasizing the fact that, if illegal immigration or drug smuggling really do qualify as an "invasion," then the Constitution authorizes states to "engage in War" as a response. In other words, Texas would be authorized to take such actions as sending its National Guard to invade Mexico, in order to attack drug cartels or forestall undocumented migration. Even if current Texas Governor Greg Abbott wouldn't do such a thing, a future governor perhaps would, if he thought it might be politically advantageous. This absurd—and dangerous—implication of Texas's argument is an additional reason to reject it.

Later in the same piece, I critique efforts to ground the invasion theory in various statements by James Madison, including the same ones Texas relies on in its brief, such as passages in Federalist 43, and one of Madison's speeches during the Virginia debate over the ratification of the Constitution.

Those who cite Madison in support of equating immigration and invasion ignore the one time he directly addressed this very question: the Report of 1800, which rebutted claims that the Alien Friends Act of 1798 (which gave the president broad power to expel non-citizens) was authorized by the Invasion Clause. There, Madison explicitly rejected the idea that immigration qualifies as invasion, emphasizing that "Invasion is an operation of war." I discuss Madison's Report of 1800 in greater detail later in the piece, and also in follow-up posts responding to Andrew Hyman and Rob Natelson (see here and here).

It may be true, as Texas claims, that an "invasion" need not be an attack by a foreign government. But it does have to be a large-scale armed assault. Immigration or smuggling don't qualify.

Finally, it's worth noting  this is not the first case in which federal courts have had to address this kind of argument. In the 1990s and early 2000s, various states filed lawsuits where they tried to use the invasion provision of the Guarantee Clause as a rationale for forcing the federal government to crack down more on illegal migration or compensate states for immigration-related expenses.

Most of the resulting decisions held that the Invasion Clause  is a nonjusticiable political question. But two federal appellate court rulings also held that illegal migration does not qualify as an invasion. In Padavan v. United States, 82 F.3d 23(1996), the US Court of Appeals for the Second Circuit held that "In order for a state to be afforded the protections of the Invasion Clause, it must be exposed to armed hostility from another political entity, such as another state or foreign country that is intending to overthrow the state's government. See The Federalist No. 43 (James Madison) (stating that the reason for the Invasion Clause is to protect the states from "foreign hostility" and from "ambitious or vindictive enterprises" on the part of other states or foreign nations)." The Third Circuit reached the same conclusion in New Jersey v. United States, 91 F.3d 463 (3d Cir. 1996).

For some reason, Texas failed to cite these precedents. Its brief also neglects Madison's Report of 1800, even as it relies on other, far less relevant statements by Madison to try to buttress its case.

These two earlier circuit court precedents are not binding on the district court adjudicating Texas' claim, which is located in the Fifth Circuit. But they are obviously relevant. The district court and Fifth Circuit judges should know they would create a circuit split if they endorse Texas' invasion argument.

In my earlier piece on this topic, I predicted that "we are unlikely to see any significant litigation over the meaning of 'invasion' as it relates to immigration, anytime soon," because in the Chinese Exclusion Case (1889), the Supreme Court held (very wrongly, in my view) that the federal government has a nearly unlimited "inherent" power to restrict immigration, without relying on the invasion clauses. I also noted that states have broad power to use military forces for law enforcement purposes even aside from the Invasion Clause of Article I, Section 10. Clearly, I didn't foresee a case like this one!

Perhaps Texas deserves to prevail in this case based on purely statutory arguments under the Rivers and Harbors Act. I take no position on that part of the issue. But courts should reject the wrongheaded and dangerous "invasion" theory.

UPDATE: In a follow-up post, I explain why Texas's position has dire implications for the writ of habeas corpus, which the federal government would have the power to suspend at virtually any time.