What Is the Insurrection Act
The Insurrection Act is a set of old laws that lets the president send the military onto American streets to enforce the law. It is the main reason troops can act like police inside the country, and it is why a president can federalize the National Guard or send active-duty soldiers to put down an insurrection or break up an obstruction of federal law. The statutes date from 1792 to 1871 and are now codified at 10 U.S.C. sections 251-255.
The Act is the big exception to a rule most people assume is absolute. The Posse Comitatus Act of 1878 bars the military from doing civilian law enforcement, and breaking it carries up to two years in prison. The Insurrection Act is the statutory hole Congress carved into that wall.
It is not one law but a stack of them. The 1792 Calling Forth Act let the president summon state militias under Congress’s constitutional power to “suppress insurrections,” and the Insurrection Act of 1807 extended that reach to the regular U.S. military. The 1807 statute is why the modern law is still often called the Insurrection Act of 1807. Three provisions survive, and the wording of each is what makes the power so elastic.
The Three Triggers, in the Statute's Own Words
| Section | What it takes | Does a state have to ask? |
|---|---|---|
| 10 U.S.C. 251 | An "insurrection in any State against its government" | Yes. The state legislature, or the governor if the legislature cannot convene |
| 10 U.S.C. 252 | "Unlawful obstructions, combinations, or assemblages, or rebellion" that make it "impracticable" to enforce federal law by ordinary means | No. The president decides alone |
| 10 U.S.C. 253 | "Insurrection, domestic violence, unlawful combination, or conspiracy" that deprives people of constitutional rights the state will not protect | No. The president decides alone |
Source: 10 U.S.C. sections 251-253, Cornell Legal Information Institute
None of those phrases is defined anywhere in the law. There is no test for when an obstruction becomes “unlawful,” no threshold for “impracticable,” and no requirement that the president show his work. Sections 252 and 253 also carry no invasions-or-request limit of the kind Article IV imposes on other federal intervention. The president “considers” the conditions met, and that is the whole procedure.
The Insurrection Act keeps civilian government running while troops enforce the law. That makes it different from martial law, where the military replaces civilian courts and government entirely. Under the Insurrection Act, judges, mayors, and police keep working. Soldiers act as an added force.
Key facts
- Two of its three triggers let the president deploy troops with no request from a state, on his own judgment that courts cannot enforce the law (10 U.S.C. 252).
- There are 33 recorded invocations across about 30 crises since 1794, and the last was the 1992 Los Angeles riots (Brennan Center).
- Twelve of those protected Black Americans or immigrants from violence. Five broke strikes, including Blair Mountain and the Pullman Strike.
- The 1792 law required Congress or a judge to approve a deployment. Those checks were stripped out after the Reconstruction era (Brennan Center).
- Through August 2026 the administration has threatened the Act repeatedly and never invoked it. Troops reached five cities under other authorities (ACLU).
If troops show up where you live, you keep your rights. The First Amendment still protects peaceful protest even when the military is on the street. Our guide to your rights at protests covers what police and troops can and cannot do.
The Insurrection Act Is Not the Only Tool
The single most common mistake about troops at home is treating every deployment as the Insurrection Act. It is not. A president has at least four separate legal tools, and they carry different powers and different checks. Sorting them out is the difference between knowing what is happening and being misled by a headline.
Four laws that put troops or military support in play, and what each one authorizes.
| Legal authority | What it does | Can troops do law enforcement? |
|---|---|---|
| Insurrection Act (sections 251-255) | Active-duty troops enforce the law as police | Yes. This is the main Posse Comitatus exception |
| Guard federalization (section 12406) | Calls National Guard into federal service only | Disputed. Whether it allows policing is in litigation |
| National Emergencies Act (50 U.S.C. 1601) | Unlocks support and logistics powers | No. Does not suspend Posse Comitatus |
| Reserve mobilization (section 12302) | Calls up reserves, used for the border | No. A separate call-up authority |
Source: Cornell LII; Brennan Center
The Insurrection Act is the strongest of the four and the one with the fewest checks. It is the only one that clearly lets the U.S. military perform domestic law enforcement. The other three either do not authorize policing at all or leave it in legal doubt. When you read that a president deployed the military, the first question is which law, because that determines whether the deployment is even lawful.
Every Invocation, 1794 to 1992
The Brennan Center has documented all 33 recorded invocations across roughly 30 crises. Laid out together they do not tell one story. They tell three, and only one of them is the story usually told.
- Protecting civil rights 12
- Other 7
- Breaking a strike 5
- Riot or civil disorder 5
- Armed revolt against federal authority 4
Two clusters carry the record: Reconstruction in the 1870s and the civil rights era in the 1960s. Nothing since 1992.
Source: Brennan Center for Justice, Guide to Invocations of the Insurrection Act, appendix.
| Year | Event | Category |
|---|---|---|
| 1794 | Whiskey Rebellion (George Washington) | Armed revolt against federal authority |
| 1799 | Fries's Rebellion (John Adams) | Armed revolt against federal authority |
| 1808 | Embargo Act enforcement (Thomas Jefferson) | Armed revolt against federal authority |
| 1831 | Arkansas-Texas border dispute (Andrew Jackson) | Other |
| 1831 | Nat Turner's Rebellion (Andrew Jackson) | Other |
| 1834 | C&O Canal labor dispute (Andrew Jackson) | Breaking a strike |
| 1861 | Secession and the Civil War (Abraham Lincoln) | Armed revolt against federal authority |
| 1871 | Ku Klux Klan terror in South Carolina (Ulysses S. Grant) | Protecting civil rights |
| 1873 | Contested Louisiana election (Ulysses S. Grant) | Protecting civil rights |
| 1874 | Brooks-Baxter War (Ulysses S. Grant) | Other |
| 1874 | Vicksburg Massacre (Ulysses S. Grant) | Protecting civil rights |
| 1874 | White supremacist coup in New Orleans (Ulysses S. Grant) | Protecting civil rights |
| 1876 | South Carolina rifle clubs (Ulysses S. Grant) | Protecting civil rights |
| 1877 | Great Railroad Strike (Rutherford B. Hayes) | Breaking a strike |
| 1878 | Lincoln County War (Rutherford B. Hayes) | Other |
| 1882 | Arizona Territory raids and cattle theft (Chester A. Arthur) | Other |
| 1885 | Tacoma anti-Chinese expulsions (Grover Cleveland) | Protecting civil rights |
| 1886 | Seattle anti-Chinese riot (Grover Cleveland) | Protecting civil rights |
| 1894 | Pullman Strike (Grover Cleveland) | Breaking a strike |
| 1914 | Colorado Coalfield War (Woodrow Wilson) | Breaking a strike |
| 1921 | Battle of Blair Mountain (Warren G. Harding) | Breaking a strike |
| 1932 | Bonus Army (Herbert Hoover) | Other |
| 1943 | Detroit riot (Franklin D. Roosevelt) | Riot or civil disorder |
| 1957 | Little Rock Nine (Dwight D. Eisenhower) | Protecting civil rights |
| 1962 | Ole Miss and James Meredith (John F. Kennedy) | Protecting civil rights |
| 1963 | Alabama school desegregation (John F. Kennedy) | Protecting civil rights |
| 1963 | Stand in the Schoolhouse Door (John F. Kennedy) | Protecting civil rights |
| 1965 | Selma to Montgomery march (Lyndon B. Johnson) | Protecting civil rights |
| 1967 | Detroit riots (Lyndon B. Johnson) | Riot or civil disorder |
| 1968 | Unrest after Dr. King was killed (Lyndon B. Johnson) | Riot or civil disorder |
| 1987 | Atlanta prison uprising (Ronald Reagan) | Other |
| 1989 | Virgin Islands after Hurricane Hugo (George H.W. Bush) | Riot or civil disorder |
| 1992 | Los Angeles riots (George H.W. Bush) | Riot or civil disorder |
The story usually told is the civil rights one, and it is real. Twelve of the 33 invocations put federal troops between Americans and the people trying to hurt them, and six of those came during the civil rights movement between 1957 and 1965. Ulysses S. Grant used the Act six times, more than any president, to break the Ku Klux Klan and reverse a white supremacist coup in New Orleans. Grover Cleveland used it twice to protect Chinese immigrants from mobs driving them out of Tacoma and Seattle. Dwight D. Eisenhower, John F. Kennedy, and Lyndon B. Johnson used it to desegregate schools and guard the Selma march.
The second story is labor. Five times the Act sent soldiers against workers: Irish canal builders in 1834, the Great Railroad Strike of 1877, Grover Cleveland breaking the Pullman Strike in 1894, the Colorado Coalfield War the year after the Ludlow massacre, and the Battle of Blair Mountain in 1921, where several thousand armed miners fought coal company forces.
A fourth group is simple civil unrest, five deployments into riots from Detroit in 1943 to Los Angeles in 1992.
The third story is the one nobody tells. In 1831 federal troops helped put down Nat Turner’s Rebellion, and the Brennan Center notes the Act’s own procedures were never followed. In 1932 Herbert Hoover’s order to clear the Bonus Army, thousands of World War I veterans camped in Washington asking for their promised bonus, ended with the Army’s top officer exceeding the commander-in-chief’s express orders and using force against American civilians.
That third story is why “the Act protected the Little Rock Nine” is true and incomplete. The same authority does whatever the president pointing it decides.
- Whiskey Rebellion George Washington leads about 13,000 troops to suppress an armed tax revolt in Pennsylvania.
- Abraham Lincoln answers secession Lincoln invokes the Insurrection Act after seven southern states secede, the largest use of the authority in American history and the opening of the Civil War.
- Ku Klux Klan Act and Reconstruction Ulysses S. Grant invokes the Act six times through 1876 to crush Klan terror, reverse a coup in New Orleans, and protect Black citizens and voters.
- Pullman Strike broken Grover Cleveland deploys troops against striking railroad workers, one of five times the Act was turned on labor.
- Little Rock desegregation Eisenhower sends the 101st Airborne to escort nine Black students into Central High after the governor defies a court order.
- Ole Miss desegregation Kennedy deploys troops so James Meredith can enroll at the University of Mississippi.
- Los Angeles riots George H.W. Bush invokes the Act at Governor Pete Wilson’s request. The last full invocation. (source)
Sources: Britannica; National Archives, Executive Order 10730.
Two centuries of the Insurrection Act, 1792-1992: 1794 — Whiskey Rebellion (George Washington leads about 13,000 troops to suppress an armed tax revolt in Pennsylvania.). 1861 — Abraham Lincoln answers secession (Lincoln invokes the Insurrection Act after seven southern states secede, the largest use of the authority in American history and the opening of the Civil War.). 1871 — Ku Klux Klan Act and Reconstruction (Ulysses S. Grant invokes the Act six times through 1876 to crush Klan terror, reverse a coup in New Orleans, and protect Black citizens and voters.). 1894 — Pullman Strike broken (Grover Cleveland deploys troops against striking railroad workers, one of five times the Act was turned on labor.). 1957 — Little Rock desegregation (Eisenhower sends the 101st Airborne to escort nine Black students into Central High after the governor defies a court order.). 1962 — Ole Miss desegregation (Kennedy deploys troops so James Meredith can enroll at the University of Mississippi.). 1992 — Los Angeles riots (George H.W. Bush invokes the Act at Governor Pete Wilson’s request. The last full invocation.).
1794: President Washington led roughly 13,000 troops to put down the Whiskey Rebellion, an armed revolt against a federal tax in western Pennsylvania. The 1807 expansion extended the authority to the regular Army and Navy.
1871: Congress passed the Ku Klux Klan Act, and President Grant invoked the Insurrection Act about 10 times between 1871 and 1876 to break up Klan terror and protect Black citizens and their right to vote during Reconstruction.
1957: President Eisenhower invoked the Act through Executive Order 10730 and sent 1,000 paratroopers of the 101st Airborne to escort the Little Rock Nine into Central High School after Governor Orval Faubus defied a federal desegregation order. Ernest Green became the first of the nine to graduate, in May 1958.
1962: President Kennedy used the Act so James Meredith could enroll at the University of Mississippi, and he used it again in 1963 to desegregate the University of Alabama. Lyndon Johnson invoked it to protect the Selma march and to respond to unrest in Detroit in 1967 and after Dr. King’s assassination in 1968.
1992: President George H.W. Bush invoked the Act at Governor Pete Wilson’s request during the Los Angeles riots. That was the last full invocation, more than 30 years ago.
In its strongest moments the Act was federal force used to make states obey the Constitution and court orders. In its worst it was federal force used against strikers, veterans, and enslaved people in revolt. Both are the same statute. Which one a given invocation turns out to be depends almost entirely on the person invoking it, which is the argument for writing limits into the law rather than trusting the office.
Why Its Checks Are So Weak
The Insurrection Act gives one person enormous discretion and almost nothing to limit it. The triggers are vague and archaic. The president “considers” whether enforcement is “impracticable,” and words like insurrection, rebellion, and unlawful combination are never clearly defined. The Brennan Center describes the result as near-limitless presidential discretion.
The courts have historically deferred, but that deference is not total. In Martin v. Mott in 1827 the Supreme Court said the president’s judgment that an emergency exists is “conclusive.” Courts can still review what the military does once deployed, a line the Court drew in Sterling v. Constantin in 1932, and in 2025 the 7th and 9th Circuits rejected the claim that an invocation is entirely beyond review.
The deeper problem is what Congress took out. The original 1792 law required a judge or Congress to approve before troops deployed, and those checks were stripped away after Reconstruction. Today there is no time limit, no mandatory report, and no congressional vote.
| Period | Value |
|---|---|
| 1792 law | Congressional or judicial sign-off required |
| Today | No limit, no report, no vote |
Enforcement of the rule it bends is weak too. The Posse Comitatus Act threatens prison for using the military as domestic police, yet there have been almost no prosecutions in 150 years, and Guard members serving in state status are not bound by it at all.
Troops in American Cities Since 2025
The Insurrection Act still has not been invoked, as of August 2026. Trump’s January 20, 2025 border proclamation directed Homeland Security and Defense to recommend by around April 20 whether to invoke it, and no invocation followed. President Donald Trump threatened it again in October 2025 over Chicago and Portland, and again in January 2026 on Truth Social, after the Trump administration sent roughly 3,000 federal agents from Immigration and Customs Enforcement to Minnesota following protests over the killing of Renée Good. The Los Angeles deployment the previous June had also grown out of protests against ICE operations. Each time the threat stopped short of a proclamation, which the Act requires.
That is the part worth sitting with. The Insurrection Act was never invoked, and troops went into American cities anyway. The administration reached for weaker authorities instead, and the weaker authorities turned out to be enough.
They are not all the same authority, and the difference decides what the law allows.
The 2025-2026 City Deployments, by Legal Authority
| City | Authority | Governor | Status |
|---|---|---|---|
| Los Angeles | Title 10, federalized | Objected | Began June 2025, wound down by January 2026 |
| Chicago | Title 10, federalized | Objected | Blocked in court, withdrawn January 2026 |
| Portland | Title 10, federalized | Objected | Enjoined, then stayed on appeal, withdrawn |
| Memphis | Title 32, state command | Consented | Began September 2025 |
| Washington, D.C. | D.C. Guard reports to the president | No governor exists | Still deployed, planned through January 2029 |
Source: Congressional Budget Office; Brennan Center for Justice; Supreme Court, Trump v. Illinois
Title 10 federalizes the Guard under presidential command, which puts the Posse Comitatus question squarely in play. Title 32 keeps troops under their governor with federal money paying the bill, which is why Memphis drew no comparable lawsuit. Washington is its own case, because the D.C. Guard answers to the president and no governor exists to object.
- $496M
- CBO estimate for the 2025 city deployments through December
- $93M
- per month to continue those deployments at the same size in 2026
- ~5,000
- troops in Washington by June 2026, up from about 2,690 in January
- 0
- times the Insurrection Act itself has been invoked
Washington is no longer a temporary deployment. Guard troops arrived in August 2025, and in July 2026 the Defense Department confirmed they will remain through Inauguration Day in January 2029. By mid-2026 several Democratic governors were threatening to withdraw their own states’ Guard members from the District.
The courts pushed back, and the record is mixed rather than a clean sweep. Judge Charles Breyer ruled the Los Angeles deployment violated the Posse Comitatus Act, calling it “profoundly un-American” and finding “no rebellion.” Judge Karin Immergut issued a permanent injunction against the Portland deployment on November 7, 2025. The California federalization fight drew 9th Circuit deference at one stage, and the administration then withdrew it on December 31, 2025, returning the Guard to the state.
The biggest ruling came from the Supreme Court, and it is about Section 12406, not the Insurrection Act. In Trump v. Illinois, decided 6-3 on December 23, 2025, the Court held that Trump likely lacked Section 12406 authority, reasoning that “regular forces” means active-duty military and that a president must show he cannot enforce the law with those forces before federalizing the Guard.
The appeals courts have since split, with the Ninth Circuit allowing the California federalization to continue on a more deferential theory while other courts blocked deployments elsewhere. That split is unresolved, and it is about Section 12406 rather than the Insurrection Act.
The takeaway sharpens the warning rather than easing it. The administration reached for the weaker, reviewable tool, courts blocked it in several cities, and one deployment outlasted all of them anyway. The Insurrection Act is the stronger tool with far fewer checks, which is why keeping it on the table is the real concern.
There is precedent for that too. The Brennan Center notes that in some past crises the mere threat of the Insurrection Act was enough to end the standoff without any deployment. Emergency powers do work that way, shaping outcomes by their availability rather than their use. A president who never signs the proclamation is not necessarily a president who declined to use the power.
Lawful Use vs Abuse
The Insurrection Act is not inherently a tool of tyranny, and pretending otherwise weakens the case against misusing it. Little Rock was a legitimate use. The honest question is how to tell a lawful invocation from an abusive one, and the distinctions are clear enough to state plainly.
How to tell a lawful invocation from an abusive one.
| Lawful use | Abuse |
|---|---|
| Enforcing a federal court order a state is defying, as in Little Rock | Overriding a state that has lost control of nothing and is defying no court order |
| A genuine breakdown of order that police cannot handle | Suppressing lawful protest, which the First Amendment protects |
| A governor or legislature requests help, or a real threshold is met | Unilateral federalization over a governor’s explicit objection |
| Specific facts show a crisis | Vague, undefined triggers let a president assert a crisis without facts |
Source: Brennan Center; Judge Breyer’s 2025 Los Angeles opinion
The line that matters most is the second row. A largely peaceful protest does not amount to a triggering event, and that was the core of Judge Breyer’s finding in Los Angeles. The First Amendment does not switch off because troops have arrived.
What Reform Would Do
Reform does not abolish the Insurrection Act. It keeps the legitimate emergency power and strips out the room for abuse, and there is broad agreement across the political spectrum on how. The Brennan Center proposes clear definitions, a seven-day limit before Congress must approve, a 24-hour report, judicial review, and a bar on suspending habeas corpus. In April 2024 a bipartisan American Law Institute group led by Bob Bauer and Jack Goldsmith called for gubernatorial consultation, a 24-hour report, a 30-day limit, and a fast-track renewal process.
Two bills in the 119th Congress, introduced in June 2025, would write these limits into law. S.2070 from Senators Blumenthal, Padilla, and Schiff, and H.R.4076 from Representative Deluzio, narrow the criteria, make troops a last resort, set a seven-day limit, and restore judicial review. Both are in committee.
The United States is an outlier among democracies in how little pre-approval it requires before troops deploy at home.
What other democracies require before the military deploys domestically, compared with the U.S.
| Country | Pre-deployment check | Who decides |
|---|---|---|
| Germany | Binding parliamentary approval for every deployment | The Bundestag, under Basic Law Article 87a |
| United Kingdom | Parliamentary convention or vote, advisory | Government with Parliament |
| Canada | Parliamentary convention or vote, advisory | Government with Parliament |
| United States | None. Only judicial review after troops deploy | The president, unilaterally |
Source: Brennan Center
Germany requires a binding vote of its parliament before any domestic deployment. The United States requires nothing in advance and offers only after-the-fact review in court. That gap is exactly what S.2070 and H.R.4076 would close.
Frequently asked questions
Did Trump invoke the Insurrection Act in 2025 or 2026? No. He directed agencies to study it and threatened it repeatedly, most recently over Minneapolis in January 2026, but as of August 2026 he has never formally invoked it. The city deployments used Section 12406 federalization or Title 32 state-status orders, which are different and weaker authorities.
Is the Insurrection Act the same as martial law? No. Under martial law the military replaces civilian courts and government. Under the Insurrection Act, civilian government keeps running and troops act as an added enforcement force. Martial law has no clear statutory basis. The Insurrection Act is codified at 10 U.S.C. sections 251-255.
Was Trump v. Illinois an Insurrection Act case? No. The Supreme Court’s 6-3 ruling on December 23, 2025 was about Section 12406 Guard federalization, and it is decided, not pending. The Court held Trump likely lacked authority under that law. It did not rule on the Insurrection Act.
Can a governor stop a president from sending in troops? Under the Insurrection Act, not directly. Section 252 lets the president act without a state request. That is part of why the weak checks matter, and why reform bills add a congressional role and judicial review.
What you can do
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Tell your senators to co-sponsor and pass S.2070. Ask them by name to support narrowing the triggers, adding a seven-day limit, and restoring judicial review. Use the letter and call script below.
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Ask your House member to co-sponsor H.R.4076. Representative Deluzio’s companion bill makes troops a last resort and adds the same limits. Ask your representative to sign on and say so publicly.
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Know the four laws so you cannot be misled. When you read that troops deployed, ask which authority was used. The martial law explainer and executive orders explainer cover the related powers a president claims.
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Read the record. See how Guard troops were used in Los Angeles a year after the ICE raids, what Operation Lone Star cost at the border, and what happened when military leaders spoke up and were purged.
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Write your representative about Insurrection Act reform. Use the letter below and ask for a clear, on-the-record position.