Following a 35-day partial government shutdown — the longest in U.S. history — President Donald Trump declared a national emergency regarding U.S.-Mexico border policy on Feb. 15, the legality of which is currently being called into question.

According to USA TODAY reporters William Cummings and John Fritze, Trump declared the emergency by circumventing Congress in order to gather funding for the wall, with its primary purpose being to prevent drug trafficking and illegal immigration.

In response to the president’s declaration, 16 states, led by California Attorney General Xavier Becerra, have challenged Trump on his plan to use $5.7 billion to pay for the wall; a recent article by Fox News writer Michelle Macaluso has broken down that cost to $17 per person. The lawsuit’s primary claim holds that the president does not have the authority to override Congress — indeed, legal scholars state that while he has made a strong effort to remain within the limits of the U.S. Constitution, the likelihood of his plan’s succeeding are slim to none.

“[The states] bring this action to protect their residents, natural resources, and economic interests from President Donald J. Trump’s flagrant disregard of fundamental separation of powers principles engrained in the United States Constitution,” reads the opening lines of the lawsuit. “Contrary to the will of Congress, the President has used the pretext of a manufactured ‘crisis’ of unlawful immigration to declare a national emergency and redirect federal dollars appropriated for drug interdiction, military construction, and law enforcement initiatives toward building a wall on the United States-Mexico border.”

The lawsuit comes as no surprise to the president, who anticipated this state-level reaction before he declared a state of emergency.

“Look, I expect to be sued … We’ll end up in the Supreme Court, and hopefully we’ll get a fair shake and we’ll win in the Supreme Court,” Trump said to reporters in the Rose Garden.

Skepticism surrounding the lawsuit persists as the aforementioned 16 states question the legality of President Trump’s attempts to supersede Congress and spend on the border wall. Those involved in the lawsuit plan to keep prosecuting the president for this possibly unconstitutional operation.