Federal troops have taken up positions at the National Mall and various neighborhoods in Washington, marking an unprecedented move by President Donald Trump to exert control over the capital’s police forces.

The Trump administration is now attempting to appoint its own emergency police commissioner, a significant step in exerting federal authority over a local government, something rarely seen in modern history.

While Washington took legal action on Friday to prevent Trump’s intervention, the outcome and whether this situation could serve as a precedent for other cities is still uncertain. Here’s an overview of the situation and potential developments:

Why is Trump taking over the police in DC?

This week, the Republican president declared his intention to seize control of Washington’s police department and activate National Guard units to curb crime, reflecting his assertive stance on law enforcement. However, officials in the District of Columbia argue that such measures are unnecessary, noting that violent crime reached a 30-year low last year and continues to decline significantly.

Can he do that?

Due to its status as a congressionally designated federal district, Trump has more leeway to assert control over D.C. than over other cities. Initially, D.C. Mayor Muriel Bowser showed little resistance, allowing city workers to dismantle homeless encampments and cooperate with federal immigration authorities. But on Friday, the primarily Democratic district sought an emergency court order to prevent Trump officials from appointing a federal official to oversee D.C. police.

So who is in charge of police in Washington?

The situation is currently unresolved. On Thursday, the Trump administration announced that the head of the Drug Enforcement Administration would assume the police chief’s responsibilities, including issuing orders to officers. It remains unclear what this means for the city’s current police chief, Pamela Smith, who answers to the mayor. Smith has warned that disrupting the command structure poses a “dangerous” risk to maintaining law and order.

What’s at stake

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.

What are the federal troops doing in DC?

About 800 National Guard troops are being activated, with Humvees parked along the Washington Monument and near Union Station. Troops have been spotted standing outside baseball’s Nationals Park and neighborhood restaurants. The White House says guard members aren’t making arrests but are protecting law enforcement officers who are making arrests and helping deter violent crime. Trump says one of the objectives will be moving homeless people far from the city.

How long can this go on?

Trump has the authority to do this for 30 days and says he might look into extending it. But that would require congressional approval. Whether Republicans in Congress would go along with that is unclear. Some D.C. residents have protested against the increased police presence. For some, the action echoes uncomfortable historical chapters when politicians used language to paint predominantly Black cities with racist narratives to shape public opinion and justify police action.

Will Trump try to take control in other US cities?

Washington is very different from any other American city, and the rules that govern it give the federal government much more control than it would have anywhere else. Whether Trump is using this as a blueprint for how to approach cities — largely Democratic cities — that he wants to exert more control over remains to be seen.