President Donald Trump’s takeover of the Washington, D.C., police department will temporarily reduce the district’s autonomy. Trump can more easily take over the Metropolitan Police Department than he can suspend the district’s home rule because ending home rule requires congressional action.

P resident Trump said Monday he would take command of Washington, D.C.’s local police force, known as the Metropolitan Police Department, under a rarely cited provision of a 1973 federal law granting home rule to the capital city’s residents. Here’s what to know about Trump’s unprecedented move.