Evolving Norms of Military Aid to Civilian Law Enforcement: Is Militarized Law Enforcement Consistent with the Rule of Law?

During the latter half of 2025, the Trump administration federalized and deployed National Guard troops to multiple cities across the United States for the stated purpose of protecting federal immigration enforcement activity and reducing crime. Chicago, Los Angeles, Memphis, Portland, and other U.S. cities, as well as the District of Columbia, saw significant National Guard troop deployments, in some cases involving deployments not only from the home state of the deployment site but involving deployments from the federalized National Guards of other states. For example, the Texas National Guard was deployed to Illinois; the California National Guard was deployed to Oregon; and National Guard troops from several surrounding states were deployed to the District of Columbia.

The legal authority for these deployments throughout much of 2025 was somewhat unclear, and multiple lawsuits were filed. The Trump administration, in numerous briefs, Office of Legal Counsel (OLC) opinions, and public statements, invoked the protective power of the federal government as well as a previously disregarded statute, 10 U.S.C. § 12406. The use of these authorities was challenged in multiple court cases, as well as in the public discourse surrounding the deployments, and most governors whose states were affected vocally opposed the deployments. California, Illinois, Oregon, and the District of Columbia took legal action to counter the federalization of their National Guard forces or the deployment of U.S. troops to their states.

The deployments enacted pursuant to 10 U.S.C. § 12406 ended with the U.S. Supreme Court’s ruling in Trump v. Illinois, 607 U.S. ___ (2025), a case that arose on the emergency docket to address the legality of the deployments in the face of gubernatorial objections. In that December 2025 ruling, the U.S. Supreme Court rejected the federal government’s application for a stay of the Illinois District Court’s injunction barring the deployment of members of the National Guard to Chicago, on the ground that Section 12406(3) required that the government be “unable with the regular forces to execute the laws of the United States”  before employing the National Guard to help with this task. The Court held that the term “regular forces” was restricted to the regular armed forces of the U.S. military, as opposed to civilian law enforcement personnel.   

Among other questions, this session will consider the impact of the Court’s ruling in Trump v. Illinois. What is the scope of the president’s authority to federalize and deploy the National Guard post-Trump v. Illinois? What view is the Court likely to take of other authorities for the invocation of constitutional and statutory presidential authority to deploy the National Guard? Does the president have the authority to deploy the National Guard to airports or to polling places under the same legal authority addressed in Trump v. Illinois, as long as he attempts to use the regular armed forces first or determines that he is unable to do so? Does Trump v. Illinois have implications for the president’s potential invocation of other authorities for the deployment of the National Guard, such as the Insurrection Act?

This session will also discuss limitations on the use of federal troops based on the Posse Comitatus Act (PCA), namely 18 U.S.C. §1385. A federal judge of the United States District Court for the Northern District of California, for example, ruled in a case involving the California National Guard that the deployment of federal troops to California violated the PCA because the tasks they were performing constituted law enforcement activity for purposes of the statute. Judge Breyer of the Northen District of California accordingly enjoined the illegal use of such troops. The Ninth Circuit subsequently stayed that injunction, and a request to rehear the case en banc was denied. In the wake of the Newsom v. Trump case, however, the question remains: Does the concept of posse comitatus pose a true limitation on the activity of federal troops? If so, what is the extent of that limitation?

In 2025, the Trump administration surged federal agents to American cities to conduct immigration enforcement operations. Recent Immigrations and Customs Enforcement (ICE) surges across the United States, including in Minneapolis and St. Paul, have raised questions surrounding their legal authority. The problem becomes all the more significant when federal agents fail to abide by the law but assert inherent presidential powers, infringing on constitutional rights and other potential legal violations.

A further complication emerges when federal agents partner with local law enforcement to voluntarily commit local authorities to operate under the supervision of CBP or ICE, thus giving the federal government the authority to call on state and local authorities to support their law enforcement activities. Signed memoranda of agreements between local law enforcement and the federal government under the 287g program give the federal government considerable ability to call on state law enforcement authorities to assist the federal government in an emergency. As of March 2026, there were 1,552 signed memorandums of agreement across 39 states establishing such arrangements between local law enforcement and the federal government.

What recourse do states have to challenge the use of their law enforcement officials for purposes they do not support, once they have entered into a collaborative arrangement with the federal government? What are the restrictions on the president’s use of what is essentially a paramilitary force, deployed first at the border, then in U.S. cities, and now at U.S. airports around the country? What recourse do states or members of Congress have to challenge the deployment of federal agents? And what limits must non-military federal agents observe when thus deployed?

This discussion will also address the various legal strategies that have thus far been explored to challenge the deployment and activities of ICE across the United States. Do federal courts supply an effective means of countering many of the extreme behaviors ICE agents have displayed when pursuing law enforcement objectives? As one federal judge emphasized in a case brought in the Minnesota District Court, the Department of Homeland Security has violated almost 100 court orders regarding its enforcement activities. Once the federal government stops listening to federal judges, is there any effective backstop to excessive uses of federal civilian agents to accomplish the same aims that National Guard were previously deployed to enforce? The ability of states to challenge the surge on a Tenth Amendment basis, such as in Minnesota v. Noem, (0:26-cv-00190), and the district court’s reasoning in that case, may yet prove useful. Other federal-state conflicts, such as the ability of a state to prosecute federal agents, will also be discussed.

The session will focus on the ability of the president to deploy U.S. military domestically in accordance with various sources of presidential emergency powers absent the invocation of presidential war powers. The Insurrection Act, the National Emergencies Act, the Stafford Act, and even the Defense Production Act could all become grounds for the deployment of federal troops pursuant to presidential emergency authority. In the face of the use of federal troops for emergency purposes, what recourse would states, members of Congress, or individuals have to challenge such a federal deployment, and what authority would federal judges have to engage in judicial review? This session will also address the legal basis (or lack thereof) for the invocation of martial law in the United States and the differences between martial law and the invocation of emergency powers under the Insurrection Act and other authorities. Is there even such a thing as martial law under U.S. federal law?

Martial law is not military law, since martial law still requires compliance with civil law. It is critical to note, for example, that under martial law, civilians can still seek remedies against the improper use of military power. Yet under martial law, military authority temporarily replaces civil authority due to the unavailability of civilian authority. The occasions on which martial law may be invoked are limited to emergency circumstances. In Ex parte Milligan, 71 U.S. 2 (1866), for example, the U.S. Supreme Court held that martial law can never exist where federal courts are open. More recently, in Mudd v. Caldeira, 26 F. Supp. 2d 113 (D.D.C. 1998) , the United States District Court of the District of Columbia held that martial law authorizes the military to take over when at least one of the three branches of government is unable to function due to war, civil unrest, natural disaster, or other emergencies.

In the United States, martial law can be declared by Congress or by the president. The most notable example is President Lincoln’s declaration during the Civil War. But the ability to declare martial law does not just lie within the prerogative of the federal government. Most states also have the power to declare martial rule, and that power is clearly outlined in their constitutions and in their laws.

There are two theories of martial law. A first view, expressed in Luther v. Borden, 48 U.S. 1 (1849), allows the states the power to declare martial law. In Luther, for example, the Court found that the Rhode Island legislature had the authority to establish martial law and combat insurrection in that state. This meant that the power to declare martial law resides principally with the highest political authority of the state. The Prize Cases, 67 US 635 (1863), gave Luther’s principle national scope. These cases represent the view that martial law is lawfully established by a legitimate political authority in wartime and is a political act. Consistent with this view was Moyer v. Peabody, 212 U.S. 78 (1909).  The Supreme Court held that the governor of a state is the final arbiter of whether a state of emergency (in that case, insurrection) exists in a state, and what actions are needed to “head the insurrection off.”

There is a different view of martial law and its applicability. According to this view, martial law is the result of necessity, and only the courts, not other political entities, can be the final judges of that necessity. Martial law cannot be established by a valid act of political authority. In Sterling v. Constantin, 287 U.S. 378 (1932), the Court replaced Moyer’s good faith standard with the “direct relation” test, where the Court held that not every sort of executive action is justified in response to an exigency.

Is martial law an act of a legitimate political authority or the result of necessity and exigency? This question is closely tied to the question of the rule of law: Can the head of the executive branch in a democratic society exercise powers during an emergency that he or she has not acquired from any legislature or directly from the Constitution? Does the president, for example, have the power to unilaterally suspend the Constitution that establishes his or her own authority because of the exigencies of war or on another emergency basis?

In numerous cases arising out of the surge of ICE agents to Minneapolis, U.S. citizens have asserted violations of their First, Fourth, Fifth, and Sixth Amendment rights, among others. Similar violations were alleged in Los Angeles during the deployment of the National Guard. The Trump administration has frequently claimed it is not obligated to abide by the constraints imposed by federal judges in view of the exercise of federal protective power and presidential authority against individual citizens, as well as non-citizens who are the objects of federal immigration enforcement action. Further, it argues that its actions are not reviewable by federal courts. Numerous legal complexities have arisen as an outgrowth of legal actions relating to ICE activities. This session will review the legal action addressed specifically to the constitutional claims brought by individuals to counter the activities of federal Homeland Security officials and consider where effective challenges can properly be mounted. In particular, it will consider the authority of federal courts to address such challenges and the many legal complexities federal challenges to CBP and ICE activities have introduced.

Among other questions, this panel will address legal challenges that might be brought if ICE or CBP agents are deployed to polling places in advance of and during the midterm elections. What are the main authorities the federal government might claim to justify the deployment of federal agents during election activities and at polling places? Are the arguments the administration may invoke subject to judicial review? What are the legal limits that pertain to large-scale civilian law enforcement operations when they infringe on the rights of Americans, and can such constitutional rights violations still be robustly addressed with federal litigation?

On January 3, 2026, the United States carried out an operation in Venezuela known as Operation Absolute Resolve, in which the U.S. military captured Nicolás Maduro and his wife, Cilia Flores, from their home, and brought them to face legal proceedings in the United States. The Trump administration released a redacted opinion from the Office of Legal Counsel (OLC) finding that the operation was consistent with presidential authority under domestic law and that the president was not bound by international law in any event.

The session will focus on the legal complexities surrounding Operation Absolute Resolve in Venezuela and the capture and rendition of Maduro. In particular, it will scrutinize the relationship between the civilian aims of the operation—as announced a civilian law enforcement operation conducted abroad to bring the Maduros to justice in the United States—and the military means selected for the operation. Moreover, the operation was never authorized by Congress as part of the president’s war powers authority. Is the characterization of military operations as “civilian law enforcement” a way of obviating the need for Congressional approval in operations making use of military force? What are the boundaries of civilian law enforcement operations, on the one hand, and true military deployments on the other? And is the president free to use federal troops on either side of that divide as long as he does not trigger restrictions relating to presidential war powers that would require congressional authorization?

Among other questions, this session will consider the reasoning of the OLC memo and its implications for other military operations such as Iran, and possibly Cuba or Greenland. Insofar as the administration does not regard the president as bound by international law, and Congress remains largely silent on the invocation of domestic war powers, what constraints remain on the exercise of presidential authority regarding the use of federal troops to conduct military operations anywhere in the world? What is the correct line to draw between federal law enforcement and federal military actions with regards to overseas operations? Does this same line hold in the domestic realm?

In another example of military aid to civilian authority, the U.S. government has continuously targeted boats in the Caribbean Sea and the Eastern Pacific Ocean, claiming they are operated by dangerous narco-terrorists, and effectively bringing the job of countering drug shipping under the framework of military authority. Yet the interception of drug traffickers, even abroad, has traditionally been a function of civilian law enforcement. This session will focus on several legal complexities arising out of the U.S. strikes on civilian drug boats.

First, the application of an expanded definition of terrorism in order to enlarge the scope of military authority has altered the traditional framework for counter-terrorism operations. What is the legal basis for treating strikes on drug boats under the auspices of military intervention in an expanded war against terror (specifically, a non-international armed conflict or NIAC), and what permissions does such framing enable? Does the president possess the sole authority to determine whether an enforcement operation is grounded in the law of war or in civilian law enforcement?

Second, if the operations against drug boats are legitimately framed as part of a NIAC, is the administration correct to claim that the strikes are legal because the individuals on the boats are “combatants” and that the strikes are a means of national self-defense? Numerous legal experts have challenged the legality of the strikes, both as violations of international human rights law and under the Law of Armed Conflict (LOAC).

Third, the Trump administration faced significant blowback for the use of a second strike on two individuals who had survived an initial strike on their boat. Secretary of Defense Pete Hegseth has also been accused of issuing what amounts to a “no quarter” order, violating international law and the Pentagon’s own policies. Secretary Hegseth has defended the second strike as taking place during “the fog of war.” Is the application of a “no quarter” rule a violation of the in bello rules of warfare in this context?

Finally, if the use of lethal force in these instances turns out to be unlawful under LOAC, what are the consequences for the individuals who participated in or otherwise authorized such strikes? Does the order to kill the shipwrecked survivors constitute a “patently” illegal order? Accordingly, might individuals in the chain of command be held liable for their participation in authoring such strikes? Might the lawyers who affirmed the legality of such strikes be professionally at risk for defending the legality of these operations?

The final session will consider the problem of the law of superior orders in the present context. It is widely known that military members must follow lawful orders, but many commentators mistakenly believe that servicemembers must also disobey all unlawful orders. Military law is more complex. It carves out a category of “apparently lawful” orders that are actually unlawful, but which do not rise to the severe level of “patently unlawful.” In this gray zone, service members can either disobey the order, or they can obey it. Most of the orders issued by the Trump administration fit into this category. Moreover, the assessment of lawfulness is one that most service members must make on their own, without the benefit of legal advice. Order-givers (commanders) have JAGs to advise them, but order-receivers (lower in the chain) are generally unable to consult uniformed counsel because they are not criminal defendants. This is despite the fact that obedience or disobedience can have severe criminal consequences. The large category of “gray zone” orders interacts with the disparity in legal advising just noted—it means that most servicemembers facing most unlawful orders will be on their own to determine how to act. This panel will explore the different challenges faced by different actors at the various levels of military hierarchy, unpacking weak points in the system and assessing areas where reform is needed.

Second, the panel will explore the implication of presidential immunity on the law of superior orders. The U.S. Supreme Court opinion U.S. v. Trump, 603 U.S. ___ (2024), creates incentives and disincentives that might lead to deleterious unintended consequences for good order and discipline. One category of service members may erroneously believe that Trump means that all presidential orders are lawful, thus obeying even patently unlawful orders. Another category might take the opposite approach, viewing presidential orders with greater skepticism, and disobey even lawful orders. Since (as noted above) most servicemembers will be on their own, chaos may result. The panel will explore ways to ameliorate the problems created by confusion about U.S. v. Trump.