The Future of Military Troops in American Cities Is Now Before the Highest Court
Across the country, legal challenges to National Guard deployments are exposing tension between federal authorities who issue orders and local authorities expected to navigate them. Poor coordination, limited transparency, and conflicting accounts of on-the-ground conditions have left communities—and courts—grappling with who has legal authority and when troop deployment is justified. Now, the U.S. Supreme Court is preparing to weigh in.
The administration’s justifications for deployments have varied, and while official documents may reference statutory authority, they rarely articulate a clear legal basis. Now, in Trump v. Illinois before the Supreme Court, the governor is challenging the president’s authority to deploy the National Guard in Chicago without the state’s consent, arguing such action violates fundamental principles of federalism. The case centers on deciding where executive power ends and state sovereignty begins. Although the upcoming decision may rest on a specific set of facts, it will carry significant weight far beyond Illinois, especially since the administration claims unfettered authority to mobilize troops without state approval. However, the Court’s request for additional briefings on the emergency appeal signals it may be reluctant to endorse this expansion of executive power without constraint.
Cases on the emergency docket, or “shadow docket,” are often decided without full briefings or oral arguments, resulting in quick, unsigned rulings with little analysis. By calling for further briefing, the Court appears poised to offer a more substantive opinion on this complex issue. It also seems inclined to assert its authority to review presidential Guard deployments—something contested by the administration—reaffirming the judiciary’s role as a constitutional check on executive power. And while the decision won’t set binding precedent for future deployments, it seems likely that it will offer important judicial guidance on when such actions are legally justified.
This clarity will offer much-needed direction to lower courts reviewing Guard deployment cases and to states preparing for related battles on the legal limits that govern what the National Guard can do and under what conditions. Under current law, the president can federalize the Guard under 10 U.S.C. § 12406 during an invasion, rebellion, or to enforce federal law when regular forces are insufficient. However, the statute does not define what constitutes “rebellion,” whether “regular forces” refers to civilian law enforcement or active duty military, or what threshold renders them “not sufficient,” leaving wide latitude for interpretation.
Even then, the Posse Comitatus Act bars federal troops from performing civilian law enforcement unless Congress authorizes it or the president invokes the Insurrection Act. The act, which authorizes such deployment to suppress insurrection, domestic violence, or obstruction of federal law when state authorities are unwilling or unable to do so, has been invoked sparingly. One notable example is President Dwight D. Eisenhower’s 1957 deployment to enforce school desegregation in Little Rock, Arkansas, after the state’s governor defied a federal court order. Its use reflects extraordinary circumstances rather than routine federal intervention in state affairs. These safeguards exist for good reason, as America was never designed for military force to replace local governance.
Several states have already sought legal relief from or against deployment.
In Oregon, a federal court recently blocked the Trump administration from deploying the National Guard to Portland, finding insufficient legal basis under 10 U.S.C. § 12406. The administration claimed Guard troops were needed to protect federal property amid ongoing protests, but testimony revealed key lapses in coordination and justification. On appeal, it became clear that the Federal Protective Service (FPS)—the agency that leads security of federal property—wasn’t informed of the Portland Guard deployment, and even two of the Department of Homeland Security’s most knowledgeable local officials on Portland Immigration and Custom Enforcement facility safety were not consulted. Even more concerning, Portland police testified that it was not local unrest, but aggressive federal tactics that provoked peaceful crowds during previous deployments. An FPS official further confirmed that those tactics triggered three internal investigations for improper use of force.
In California, a federal court ruled that the deployment of National Guard troops partially violated the Posse Comitatus Act by allowing them to engage in direct law enforcement activities (e.g., crowd control, detentions); however, the court permitted the Guard to continue supporting federal property protection and logistical operations while the case proceeds on appeal. A decision from the Ninth Circuit is pending.
State-ordered deployments on behalf of the administration have also caused friction.
Courts in Tennessee and West Virginia held hearings this week on the deployment of National Guard troops to Memphis and Washington, D.C., respectively. In both cases, governors sent troops to support local crime control efforts. Unlike concerns in other states around federal overreach, these disputes focus on whether military forces should be policing neighborhoods and whether it is a responsible use of public resources.
Now, the Department of War is forming “quick action forces” with 23,500 specially trained National Guard troops stationed across all states and territories for rapid response to “civil disturbances.” This expanded federal posture indicates the potential for more military involvement in civilian life and the threat of heightened tension between public safety efforts and the legal boundaries on federal power.
As a result, concerns are mounting over how this power is being used and how it might evolve. Some warn that military deployments could be used for intimidation and voter suppression, while others argue that the pattern of disproportionately targeting blue states or urban areas led by opponents suggests a political motive. Even current and former National Guard members have voiced unease about being drawn into missions that blur the line between public safety and political strategy. What’s clear is that the administration is gradually normalizing the domestic deployment of the Guard in response to unrest.
On the other hand, some see this as a useful tactic to execute on a strict anti-immigration agenda. Some law enforcement have welcomed the idea of Guard support, likely due to years of staffing shortages, rising pressure for higher clearance rates, and the growing burden of handling homeless crises with too few resources. Previous administrations have emphasized that “the federal government is ill equipped—in terms both of laws and of personnel—to perform ordinary police functions” and should only be used as a “last resort.” Moreover, military deployments offer only short-term relief and do little to address the deeper, long-term challenges of sustaining public safety.
The Supreme Court’s decision may not draw a bright line on when or how the president can deploy the National Guard, but it will still matter. What’s most critical is that the Court affirms its authority to review such actions and preserves the role of judicial oversight in checking executive power. If the Court signals support for broader federal deference, even in part, future deployments are likely to become more frequent. In that case, state and local leaders must be prepared with clearer coordination plans, stronger communication protocols, and a shared understanding of what deployment should look like when it occurs, regardless if they support it or not. The groundwork to protect public safety and constitutional rights must be laid now.