Preventing the Use of the National Guard to Evade the Posse Comitatus Act

Elizabeth Goitein is senior director of the Liberty & National Security Program at the Brennan Center for Justice at NYU Law School.

Limitations on military involvement in civilian affairs have been a central feature of Anglo-American law for centuries. Armies are equipped and trained to vanquish enemies. If turned inward, they can easily become an instrument of tyranny—as seen in authoritarian regimes around the world. To prevent such an outcome, the Posse Comitatus Act (PCA) generally prohibits federal armed forces from conducting law enforcement in the United States.

The PCA, however, is replete with gaps and loopholes. Several of them relate to deployments of the National Guard. In theory, the Guard should be subject to the PCA when acting under the president’s command and control. Yet there are circumstances in which National Guard forces may operate under the actual or effective command of the president without being subject to the PCA. Moreover, the rationale for prohibiting federal armed forces from enforcing civilian law is increasingly applicable to National Guard forces even when they are operating entirely under state control.

As this series underscores, a rethinking of the legal framework for the National Guard is long overdue. As part of that process, Congress and state legislatures should close the legal loopholes that enable use of the Guard in violation of the principle of posse comitatus. This will entail updating the command and control of the Washington, D.C., National Guard; clarifying the scope of 32 U.S.C. § 502(f), under which Guard members perform federal missions under state command and control (as Professor Mark Nevitt discusses further in his commentary); and expanding principles of posse comitatus at the state level.

Control of the D.C. National Guard: A Relic of History

The PCA applies to every branch of the federal armed forces except the Coast Guard. The National Guard normally operates in State Active Duty status; it is considered part of the federal armed forces only when called into federal service. That is generally the sole circumstance in which Guard forces are formally under the command and control of the president.

There is one notable exception, however. The D.C. National Guard always operates under the president’s command and control. This is not because D.C. lacks statehood; the National Guards of Guam, Puerto Rico, and the U.S. Virgin Islands are all under local control unless federalized. It is, instead, a relic of history. Congress originally assigned command and control to the president in the 1800s, when D.C. had no independent local government or leader to assume command of the Guard.

Even though the D.C. National Guard is always under the president’s command, the Department of Justice has adopted the legal fiction that it can operate in a nonfederal “militia” status. In that status, the department has opined that the Guard is not subject to the PCA. This conclusion is in notable tension with case law holding that presidential command and control triggers PCA application. In practice, it means the president may use the D.C. National Guard for law enforcement without having to invoke the Insurrection Act or any other PCA exception.

The president can supercharge this authority by bringing other National Guard forces into the mix. In June 2020, 11 governors sent their Guard forces into D.C. at President Trump’s request to suppress protests over the police killing of George Floyd. (Several other governors refused the request.) Even though these out-of-state Guard forces were nominally under their governors’ command and control, they coordinated efforts through the D.C. Guard’s chain of command. As a result, more than 5,000 Guard forces were operating under the president’s effective command and control—free from the constraints of the PCA.

Title 32: The “Hybrid” Loophole

Another significant loophole lies in Title 32 of the U.S. Code, under which the National Guard acts in “hybrid” status. As detailed in Professor Nevitt’s analysis, this means the Guard remains under state command and control but performs missions set by Congress or the president and is paid by the federal government.

This hybrid status raises significant PCA concerns. Guard forces performing a federal mission, even if legally under the command and control of their governor, may of necessity be following federal direction. When that direction comes from the president through the Department of Defense, it starts to look very much like the command and control that should trigger the PCA. But because the Guard has not been called into federal service, the PCA does not apply.

Until relatively recently, the scope of this loophole was limited by the activities authorized under Title 32, which included training exercises and related duties, certain counterdrug activities, and homeland security functions. In 2006, however, Congress amended Title 32 to authorize “operations or missions undertaken . . . at the request of the President or Secretary of Defense.” As Professor Nevitt points out, the legislative history of this amendment, codified at 32 U.S.C. § 502(f), strongly suggests that its intent was to facilitate payment for natural disaster responses. But President George W. Bush quickly leveraged the open-ended language to request state deployments of National Guard forces at the southern border. And in 2020, when Trump asked governors to deploy their Guard forces to D.C., he relied on Section 502(f)—the first time Title 32 had been used to quell civil unrest.

Few circumstances implicate the concerns at the heart of the PCA more than the president’s use of the military to police protest activity. Compounding those concerns, the governors sent their Guard forces to D.C. over the objections of D.C.’s mayor. Although D.C. is a federal district, the rationale that Attorney General William Barr articulated for this nonconsensual cross-border deployment—the need to protect federal functions, persons, and property—could also apply to interstate deployments. In other words, there is a risk that a president could interpret Section 502(f) to authorize the deployment of a state’s National Guard forces into another state without the receiving state’s consent.

Such a deployment would not only be unconstitutional (as the Brennan Center’s Joseph Nunn and the author have argued elsewhere); it would gravely undermine the PCA. As previously noted, a governor’s command and control may be more theoretical than actual when Guard forces are performing federal missions—with one key exception. A core element of command and control is the decision whether to use the military at all. Governors retain this discretion under Section 502(f); the president and secretary of defense may only “request” deployment. If, however, a governor can deploy National Guard forces into an unconsenting state, the ability to decline becomes meaningless. All the president needs is one willing governor to deploy the National Guard for law enforcement purposes anywhere in the country.

Today’s National Guard: Citizen Soldiers?

The PCA workarounds described here are all possible because the PCA does not apply to the National Guard when operating in nonfederal status. That state of affairs might be worth reconsidering in light of the Guard’s evolution in recent decades.

In the past, the active-duty armed services and the National Guard differed significantly in their culture, training, and experience. Active-duty service members, then as now, belonged to a full-time professional fighting force that periodically deployed overseas to combat foreign enemies. National Guard members traditionally acted as “citizen soldiers,” holding ordinary jobs during the week and training on the weekends. Although available to be called up and deployed as a reserve force, their usual remit involved responding to needs within their own communities, such as disaster relief or search-and-rescue missions.

Today, this distinction has become blurred. Since the 1970s, the Department of Defense has pursued a “Total Force Policy” with the goal of integrating all of the U.S. armed forces—including the National Guard and reserve components—into “a seamless and holistic ‘total force.’” Guard members now train—and, increasingly, fight—alongside active-duty forces. Since 9/11, lengthy overseas deployments have become commonplace; nearly half of U.S. troops deployed to Iraq and Afghanistan were members of the National Guard or reserves. In 2010, the acting director of the National Guard’s domestic operations proudly stated that the Guard had transformed from a “strategic reserve” into “a battle-tested, hardened organization . . . with many combat veterans.”

As described in a 2024 Brennan Center report, the Guard in its current form “resembles far more closely the kind of standing army that the framers feared than it does the local militias with which they were familiar.” As such, the Guard’s participation in law enforcement activities raises many of the same concerns that are triggered by participation by federal armed forces.

Solutions: Expand the Coverage of the PCA

Fortunately, these problems are all amenable to legislative solutions. The best way to close the D.C. Guard PCA loophole is for Congress to transfer command and control of the Guard to D.C.’s mayor (as Representative Eleanor Holmes Norton proposed). As with the Guard of any state or federal territory, the president would retain the authority to federalize the D.C. Guard in appropriate circumstances. This solution, however, is politically challenging, as those who oppose D.C. statehood see it (however wrongly) as a step in that direction. A less fraught alternative would be for Congress to extend the PCA to cover the D.C. Guard except in cases where the mayor has requested deployment to meet local needs.

As for Section 502(f), missions performed at the request of the president or secretary of defense are likely to involve significant federal control. Accordingly, Congress should extend the PCA to these missions. In addition, Congress should clarify that National Guard forces in Title 32 status may not deploy into states that withhold consent for such deployment (as Representative Mikie Sherrill (D-NJ) proposed).

Imposing PCA-like restrictions on National Guard forces in State Active Duty status is a more difficult matter. Congress arguably has the authority to do so; even when operating under state command and control, the Guard is subject to extensive federal regulation. Such a move, however, could generate substantial blowback from the states. A more realistic solution, albeit an incomplete one, is for state legislatures to enact their own versions of the PCA—i.e., to prohibit the Guard from performing law enforcement functions except as explicitly authorized in state law. Legislators might well decide to permit a broader range of law enforcement activity than Congress has authorized for federal forces, but legislative authorization would be the touchstone.

These solutions would be effective, and they are straightforward exercises in legislative drafting. But they are likely to face hurdles in Congress and state legislatures. Some will view them through a partisan lens, objecting to any constraints on an executive from their own party. Others will have genuine concerns over precluding the use of Guard forces to meet unforeseen law enforcement needs. In both cases, it might take a serious overreach—by the president or by a governor—to convince these legislators that the greater risk lies in inadequate checks. They may not have long to wait.

About the Commentary Series

In February 2024, the Center for a New American Security (CNAS) launched a project on federalism and national security. This portfolio has taken shape under the CNAS Securing U.S. Democracy Initiative. Recognizing that the 21st-century United States increasingly relies on its system of federalism to rebalance the centers of power and authority across a range of public policy issues, the Securing Democracy Initiative has developed a body of work focused on states’ authorities, roles, and responsibilities that relate to national security functions. Increasing reliance on the U.S. federalist system of government presents both challenges and opportunities for strengthening national security. This commentary series and the December 2024 report Stress Testing State Power: When Governors and Presidents Diverge on Matters of National Security are components of this research effort.

Each commentary in this series explores a current trend or dynamic in modern uses and authorities of the National Guard. Expert authors explore how the Guard is currently being used and will be increasingly called upon in years ahead. Authors provide recommendations for modernizing and clarifying legal authorities for National Guard deployment, and for legislative action at the state and federal levels.

The CNAS project on federalism and national security is made possible with the generous support of the Democracy Innovation Fund, Defending Democracy Together Institute. As a research and policy institution committed to the highest standards of organizational, intellectual, and personal integrity, CNAS maintains strict intellectual independence and sole editorial direction and control over its ideas, projects, publications, events, and other research activities. CNAS does not take institutional positions on policy issues, and the content of CNAS publications reflects the views of their authors alone. In keeping with its mission and values, CNAS does not engage in lobbying activity and complies fully with all applicable federal, state, and local laws. CNAS will not engage in any representational activities or advocacy on behalf of any entities or interests and, to the extent that the Center accepts funding from non-U.S. sources, its activities will be limited to bona fide scholastic, academic, and research-related activities, consistent with applicable federal law. The Center publicly acknowledges on its website annually all donors who contribute.