The Insurrection Act gives U.S. presidents the authority to deploy active duty military to maintain or restore peace in times of crisis. The Insurrection Act was invoked numerous times in the 20th century, most famously when Dwight D. Eisenhower sent the 101st Airborne Division to enforce the desegregation of public schools in Little Rock, Arkansas.

But the origins of the Insurrection Act date back more than 200 years to a bizarre chapter in American history—when Aaron Burr plotted to raise an army and establish his own dynasty in either the Louisiana Territory or Mexico.

Burr, a decorated Revolutionary War officer and senator from New York, served as vice president during Thomas Jefferson’s first term. Burr had grand political aspirations, but they were dashed after he killed his rival Alexander Hamilton in a duel in 1804.

After Duel With Hamilton, Burr Sets Sights on Louisiana

Burr was never arrested or tried for Hamilton’s murder, but it effectively ended Burr’s political career. With no prospects in Washington, D.C. or New York, Burr set his sights on the West, namely the newly acquired Louisiana Territory and Mexican-owned lands in the Southwest.

The details of Burr’s plot were never clear, but it involved mustering an army to invade Mexico under the pretense of a war with Spain, and then keeping the conquered land for himself. Burr thought he had an ally in General James Wilkenson, commander of the U.S. Army and first governor of the Louisiana Territory, but when rumors of Burr’s plot leaked into the newspapers, Wilkenson turned on his co-conspirator.

In a letter sent on October 21, 1806, Wilkenson spilled the details of the plot to Jefferson without mentioning Burr by name. But Jefferson had already grown concerned enough about Burr’s strange activities that Jefferson had sent his own letter to Secretary of State James Madison asking if the Constitution granted him authority to deploy the army to stop a rebellion.

General James Wilkinson, the Insurrection Act
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General James Wilkenson

In his reply, Madison said no. “It does not appear that regular Troops can be employed, under any legal provision agst. insurrections,” wrote Madison, “but only agst. expeditions having foreign Countries for the object.”

Both Jefferson and Madison were strict interpreters of the Constitution and wouldn’t dare exercise authority that wasn’t explicitly written in the founding document, so they needed to convince Congress to give Jefferson that power. And to do that, they first needed proof of Burr’s conspiracy. That’s where Wilkenson’s letter comes in.

“Jefferson was looking for a legitimate source of authority on Burr’s plot and he was willing to believe Wilkenson, even though historians suggest that Jefferson knew darn well that Wilkenson was a liar with his own suspect reputation,” says John Fea, a history professor at Messiah College. “But Jefferson needed a source to move the gears to try to stop Burr, who was his biggest fear.”

Jefferson Orders Burr's Capture

Armed with Wilkenson’s “proof,” Jefferson issued a proclamation on November 27, 1806, that laid out the plot and enjoined all military officers, both state and federal, to “to be vigilant… in searching out and bringing to condign punishment all persons engaged or concerned in such enterprise, in seizing and detaining, subject to the disposition of the law, all vessels, arms, military stores, or other means provided or providing for the same, and, in general, in preventing the carrying on such expedition or enterprise by all lawful means within their power.”

Aaron Burr, the Insurrection Act
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Aaron Burr

“Jefferson essentially puts a bounty on Burr’s head,” says Fea, and within weeks, an Ohio militia seized boats belonging to Burr’s ragtag army and raided a private island on the Ohio River that served as a military encampment.

But Burr evaded capture and rumors continued to swirl that he was recruiting soldiers en route to the Louisiana Territory and soliciting help from Britain to establish his spinoff nation in the West. Jefferson still refused to deploy the standing U.S. Army to track down Burr and quash the rebellion once and for all, a reticence that was mocked by his political enemies, the Federalists.

“Jefferson, to his credit, says I’m not going to act unless the Constitution says I can act,” says Fea. “The Federalists take a much broader view of the Constitution. If the Constitution doesn’t outright condemn it, then it’s OK.”

Jefferson stuck to his principles and in December of 1806 asked Congress to pass a bill “authorizing the emploiment of the land or Naval forces of the US. in cases of insurrection.” This legislation, known as the Insurrection Act, would take another three months to become law. When it was finally signed on March 3, 1807, Aaron Burr had already been in custody for 11 days.

So while the Insurrection Act was written expressly to foil Burr’s plot, it wasn’t used to capture him. The very first time the Insurrection Act was actually invoked was a year later in 1808 when American merchant ships in the Great Lakes flouted Jefferson’s trade embargo with the British. In response, Jefferson accused the rogue traders of “forming insurrections against the authority of the laws of the United States” and authorized the military to take action.

When Has the Insurrection Act Been Invoked?

Why Eisenhower Called in the 101st Airborne After Brown v. Board, Little Rock Nine
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Minnijean Brown, 15, one of the Little Rock Nine, arrives outside Central High School, as members of the 101st Division of the Airborne Command stand ready to protect them, under orders from President Dwight Eisenhower, in Little Rock, Arkansas, on September 25, 1957.

Since 1807, the Insurrection Act has been amended several times to meet different political challenges.

In 1861, Abraham Lincoln expanded the law to form the legal basis for waging the Civil War. Without it, he wouldn’t have had the authority to send federal troops into a state without the governor’s permission.

After the Civil War, the Insurrection Act was further amended to give the president authority to enforce the 14th Amendment and the conditions of Reconstruction in the South. That authority is now found in Section 253 of Title 10 of the U.S. Code, which gives the president the right to take military action within a state when “any part or class of its people is deprived of a right, privilege, immunity, or protection named in the Constitution and secured by law, and the constituted authorities of that State are unable, fail, or refuse to protect that right, privilege, or immunity, or to give that protection.”

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That’s the same authority invoked during the civil rights era by Presidents Eisenhower and John F. Kennedy to deploy troops to the South to enforce desegregation in defiance of governors.

The Insurrection Act was last invoked in 1992 under President George H.W. Bush, after Peter Wilson, then-governor of California, requested help to quell widespread riots after four police officers charged in the beating of Rodney King were acquitted. 

In 2005, after Hurricane Katrina devastated Louisiana and the Gulf Coast, President George W. Bush explored expanding the Insurrection Act to place command of the region's National Guard under federal control. Ultimately, Bush declined to invoke the act, although it was eventually amended in 2006 to broaden the scope under which the president may act under the law.