The Insurrection Act

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.

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.

The Insurrection Act is the strongest of the four and the one with the fewest checks. 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.

The Few Times It Has Been Used

The clearest legitimate uses of the Insurrection Act were federal power deployed against states that defied the Constitution, and that history is why the modern threat reads as a reversal. The Act emerged with the 1792 Calling Forth Act, put down the 1794 Whiskey Rebellion, armed Reconstruction against the Klan in the 1870s, escorted the Little Rock Nine into a desegregated school in 1957, and was last fully invoked during the 1992 Los Angeles riots.

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. Using it the other way, to override a state that has lost control of nothing, would invert its purpose.

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.

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 was not invoked in 2025 or 2026. Trump’s January 20, 2025 border proclamation directed the Departments of Homeland Security and Defense to recommend by around April 20 whether to invoke it, and no invocation followed. He has threatened it repeatedly, saying “I’d do it if it was necessary. So far it hasn’t been necessary.” As of June 2026 there has been no formal invocation.

Instead, every domestic deployment used Section 12406, the weaker Guard federalization law, over governors’ objections. The administration sent federalized troops into Los Angeles in June 2025 with about 4,000 California Guard members and 700 Marines during immigration protests, then into Washington, Memphis, Portland, and Chicago over the following months.

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 takeaway sharpens the warning rather than easing it. In 2025 the administration reached for the weaker, reviewable tool, and courts still blocked it in several cities. The Insurrection Act is the stronger tool with far fewer checks, which is why keeping it on the table is the real concern. By January 21, 2026 the Los Angeles, Chicago, Portland, and Memphis deployments had ended, while Washington remained contested.

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.

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.

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, but as of June 2026 he never formally invoked it. Every 2025 deployment used Section 12406 Guard federalization, a different and weaker law.

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

1. 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.

2. 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.

3. 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.

4. 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.

5. Write your representative about Insurrection Act reform. Use the letter below and ask for a clear, on-the-record position.