U.S. President Donald Trump is presiding over one of the most dramatic transformations of Washington, D.C., in a generation, as he makes monumental changes to the historic White House complex, federalizes local police as part of a “beautification” campaign,

The lawsuit brought by Washington says Trump exceeded his authority under the Home Rule Act of 1973 in taking over the Metropolitan Police Department.

The showdown in Washington is the latest attempt by Trump to test the boundaries of his legal authority to carry out his tough-on-crime agenda, relying on obscure statutes and a supposed state of emergency to speed up the mass deportation of people in the United States illegally.