In August, President Donald Trump and Secretary of Defense Pete Hegseth (who was appointed by Trump) authorized the use of troops in Washington DC. They sent 800 members of the National Guard into the capital and declared local police under federal control in order to reduce crime in the area, despite local authorities claims that crime was already going down on its own.

And this wasn’t the first time this happened. Back in June, President Trump deployed troops to Los Angeles. On Tuesday, September 2nd, a federal judge ruled that the deployment of troops to LA back in June in response to protests against immigration violated a federal law that bans the use of federal troops for domestic law enforcement. 

“Martial Law” is a vague term used to refer to a federal power taking over a civilian government. What counts as martial law is different for different places, but the US has no clear outline of what counts as martial law. There is little precedent for what’s going on now, so what qualifies as martial law, as well as the laws against using troops domestically, are complicated.

The Insurrection Act of 1807, signed by Thomas Jefferson while America was still finding its bearings, allows the president to deploy troops across the country to assist with local law enforcement as they please. But the Posse Comitatus Act, signed 1878, declares that it is illegal for federal forces, especially troops, to enforce the law on civilians on a city or state level in a way that would resemble martial law without approval from congress first.

This act was also the one cited by the judge that ruled Trump’s troops in LA as illegal.

There is no confirmation of whether or not Trump’s deployment of troops to DC was authorized by congress, or that Posse Comitatus protects cities outside of states like Washington DC.