On February 15, President Trump declared a national emergency to fund the construction of a 1,000-mile wall on the border with Mexico after Congress provided money for only a sliver of the project.
The announcement came as the president signed a spending deal negotiated by Democrats and Republicans in Congress that included $1.375 billion for border fencing, but not the $5.7 billion Trump had been demanding for construction of a much longer wall. The agreement headed off what would have been the second shutdown of the federal government in the space of a month over the issue. But Trump’s declaration prompted lawsuits that set up a constitutional showdown over the separation of powers and the president’s authority.
Here’s what you need to know to understand the battle over the emergency declaration.