By: Rachel Creighton
Published: March 20, 2026
In August of 2025, over 2,000 National Guard members arrived in the nation’s capital. Today, the Guardsmen are still patrolling the District of Columbia (D.C.).[1] D.C. was the first of several cities to which the Trump administration deployed the National Guard “to combat crime, quell protests, or safeguard ICE facilities and personnel.”[2] Chicago, Memphis, and Los Angeles are among the numerous cities that experienced the highest extent of occupation, contributing to the estimated $496 million spent on domestic deployments in 2025 alone.[3] Despite governors and judges fighting back against federal overreach, the Trump administration has petitioned the Supreme Court for approval to continue what they view as “Restoring Law and Order.”[4] While safeguards such as the Posse Comitatus Act and Title 10 of the U.S. Code place limitations on federal command and control over the National Guard, the Insurrection Act could be just the legal loophole that defeats them both.[5]
The National Guard is unique in many ways compared to its active-duty counterparts. Serving in fifty-four separate organizations in all fifty states and U.S. territories, Guardsmen are reservists subject to the command of a bilateral authority: state and federal government.[6] Under Title 32 of the U.S. Code, the Guard operates under a state governor to perform domestic missions, such as responding to extreme weather events.[7] Meanwhile, Title 10 allows the president to federalize the Guardsmen in one of two ways. The first method is Section 12406 of Title 10 which “allows for activation to repel invasion, suppress rebellion, or execute federal law;” however, this authority is notably limited by the Posse Comitatus Act, prohibiting the military from acting as law enforcement.[8] The second method is the Insurrection Act which “authorizes the president to deploy military forces inside the United States to suppress rebellion or domestic violence or to enforce the law in certain situations.”[9] Unlike Section 12406, the Insurrection Act suspends Posse Comitatus which allows the president to order the military to assist state law enforcement police civilians. [10] While Trump has yet to invoke the Insurrection Act, if invoked it would likely succeed.
The Trump administration could succeed in invoking the Insurrection Act based on the law’s broad and vague language alone. Sections 251-253 of Title 10 outline the three common mechanisms for deploying the National Guard: (1) the state legislature or governor requests troops; (2) the President determines that there are “unlawful obstructions…rebellion against the authority of the United States, [which] make it impracticable to enforce the laws of the United States in any state;” or (3) states are unable or unwilling to protect their cities executing state laws.[11] Nowhere in the text of the Insurrection Act are there definitions for crucial terms such as “insurrection” or “rebellion”.[12] The ambiguity of what qualifies as a “rebellion” has been an issue of contention in lower court rulings.[13] Nevertheless, the Insurrection Act has been invoked by several presidents for a variety of reasons—from responding to rebellions against federal powers to intervening in labor disputes.[14] The most notable uses of the Insurrection Act arise from presidents defying Southern state officials and ordering that the Guard desegregate public places.[15] This fluid history of ambiguity surrounding “rebellion” supports the case for lawfully deploying the National Guard.
Looking to case precedent, in , the Court held that “the authority to decide whether the exigency has arisen, belongs exclusively to the President.”[16] The Court reasoned that if a superior officer has the right to contest the president’s orders based on his own doubt, then that right is shared by his fellow inferior officers.[17] The Court opined that not only would a potential mutiny prove disastrous, but it would also be unjustified in many cases due to the classified information privy only to the president.[18] Accordingly, Trump could argue that he reserves the right to decide what necessitates National Guard deployment based on executive discretion.
The sitting Supreme Court has permitted the executive branch to fire thousands of government workers, deport migrants without due process, and discharge transgender troops.[19] With a majority conservative Supreme Court—three of whom are Trump appointees—the recent pattern of coalescence leans in favor of rationalizing the deployment of the National Guard into prominent U.S. cities without any legal repercussion.[20] While lower courts continue to block Trump’s deployment of the National Guard or fight to remove Guardsmen from their state, the chances of permanent success are not in their favor. The historic flexible interpretation of the Insurrection Act’s vague language and the prowess of executive discretion do not lend themselves to the retraction of military presence in the near future.
[1] See generally Juliana Kim, Where Has Trump Suggested Sending Troops? In Cities Run by Democratic Mayors, NPR, https://www.npr.org/2025/10/10/nx-s1-5567177/national-guard-map-chicago-california-oregon (Oct. 16, 2025, 9:32 PM).
[2] See id.
[3] See Julianna Kim, Trump’s National Guard Deployments Could Over $1 Billion This Year, CBO Projects, NPR, https://www.npr.org/2026/01/28/nx-s1-5690394/national-guard-deployments-cost-cbo (Jan. 28, 2026, 6:33 PM).
[4] See Kat Lonsdorf & Ayana Archie, Trump Administration Asks Supreme Court to Allow National Guard Deployment in Illinois, NPR, https://www.npr.org/2025/10/17/nx-s1-5578266/trump-supreme-court-national-guard-illinois (Oct. 17, 2025, 9:29 PM) (explaining that judges and state officials have denied needing Guardsmen sent to their states); see also Steven Greenhouse, Bravo to the Judges Standing Up to Trump in Chicago and Portland, The Guardian (Oct. 19, 2025), https://www.theguardian.com/commentisfree/2025/oct/19/judges-trump-chicago-portland (stating that Chicago and Portland judges have blocked Trump’s deployment orders in court); Presidential Memorandum, Restoring Law and Order in the District of Columbia (Aug. 11, 2025), https://www.whitehouse.gov/presidential-actions/2025/08/restoring-law-and-order-in-the-district-of-columbia/.
[5] See generally Mark Nevitt, Congress Must Clarify the National Guard’s Section 502 Legal Authorities, Ctr. for a New American Security (May 13, 2025), https://www.cnas.org/publications/commentary/congress-must-clarify-the-national-guards-section-502-legal-authorities (listing the restrictions for Title 10 that include the Posse Comitatus Act); see also Charles International Law Commentary, Federalization of the National Guard & Domestic Use of Federal Forces (June 8, 2025), https://www.charlesinternationallaw.com/federalization-of-the-national-guard-domestic-use-of-federal-forces (noting that the principal exception to Title 10 is the Insurrection Act).
[6] See generally Council on Foreign Relations, What Does the U.S. National Guard Do? (Mar. 4, 2024), https://www.cfr.org/backgrounder/what-does-us-national-guard-do; see generally Charles International Law, supra note 5.
[7] See Charles International Law, supra note 5.
[8] See generally Nevitt, supra note 5; see generally Posse Comitatus Act, 1878, ch. 263, § 15, 20 Stat. 145 (codified as amended at 18 U.S.C. § 1385).
[9] See Joseph Nunn, The Insurrection Act Explained, BRENNAN CENTER FOR JUSTICE (Apr. 21, 2022), https://www.brennancenter.org/our-work/research-reports/insurrection-act-explained (stating that the military can perform law enforcement activities).
[10] See id.; see generally 10 U.S.C. § 251 (2023); see generally 10 U.S.C. § 252 (2023).
[11] See Nunn, supra note 9; see generally 10 U.S.C. § 251 (2023); see generally 10 U.S.C. § 252 (2023); see generally 10 U.S.C. § 253 (2023); see also Newsom v. Trump, No. 25-cv-04870-CRB, 2025 WL 1234567 (N.D. Cal. Sept. 2, 2025) (laying out different insurrection prerequisites).
[12] See Nunn, supra note 9.
[13] See Newsom v. Trump, No. 25-cv-04870-CRB, 2025 WL 1234567, at *1 (demonstrating judges arguing against sufficient evidence that supports their states having rebellions).
[14] See generally Nunn, supra note 9.
[15] See id. (explaining that southern states defied the Supreme Court’s order of desegregation during the civil rights movement).
[16] See id.; see generally Martin v. Mott, 25 U.S. (12 Wheat.) 19, 30 (1827) (establishing the president’s exclusive authority to dictate what constitutes an emergency that warrants calling up the militia).
[17] See Martin, 25 U.S. at 30.
[18] See id. at 19, 31.
[19] See Adam Liptak, Supreme Court Keeps Ruling in Trump’s Favor, But Doesn’t Say Why, N.Y. Times (July 16, 2025), https://www.nytimes.com/2025/07/16/us/politics/supreme-courts-shadow-docket.html.
[20] Vincent Martin Bonventre, 6 to 3: The Impact of the Supreme Court’s Conservative Super-Majority, N.Y. State Bar Ass’n (Oct. 31, 2023), https://nysba.org/6-to-3-the-impact-of-the-supreme-courts-conservative-super-majority/.