The DC National Guard began appearing in the nation’s capital on Tuesday after President Donald Trump announced a day earlier he is deploying guard troops and placing Washington, DC’s police department “under direct federal control,

While it is mostly called to respond to state-level emergencies, the National Guard has also been called to enforce law. The DC National Guard is primarily under federal control.

A federal judge is hearing arguments on whether military troops deployed this summer by the Trump administration to Los Angeles violated a federal law that bars troops from conducting law enforcement duties within the country.