What is a national emergency? Can Trump declare one for the wall?

US President Donald Trump will sign a funding bill that will avert another government shutdown, the White House said on Thursday. But he also plans to declare a national emergency to circumvent Congress to obtain funds to build a wall on the United States’s southern border. 

Democrats have vowed to respond appropriately to any declaration, saying it would be a “lawless act”. 

Trump began weighing whether to declare a national emergency after Democrats refused to cave to his demand for $5.7bn in funding for the wall, prompting a 35-day government shutdown – the longest in US history. 

That shutdown ended last month after Trump, his fellow Republicans and Democrats came to an agreement to open the government while talks continued on border security. 

Facing a Friday deadline, congressional leaders came to an agreement earlier this week aimed at keeping the government open. Although it includes $1.37bn in funding to help build physical barriers on the border, it does not include money for concrete walls, forcing Trump to look elsewhere for funding.   

“President Trump will sign the government funding bill, and as he has stated before, he will also take other executive action – including a national emergency – to ensure we stop the national security and humanitarian crisis at the border,” White House Press Secretary Sarah Sanders said in a statement on Thursday. 

But any declaration would almost certainly face a legal challenge. 

Here’s a look at what a national emergency is, and why Democrats and many experts say Trump does not have the legal authority to declare one in this context. 

What is a national emergency? What will happen once it’s declared?

US federal law gives a number of powers to the president to use in response to a “crisis, exigency, or emergency circumstances threatening the nation”, a document prepared for Congress states. He can do so at will. 

Declaring a national emergency allows the president to meet the problems of “governing effectively” in times of crisis. They also allow the president to “seize property, organise and control the means of production, seize commodities, assign military forces abroad, institute martial law, seize and control all transportation and communication, regulate the operation of private enterprise, restrict travel, and, in a variety of ways, control the lives of United States citizens,” the document states.

Declaring a national emergency is a rare step. In this case, it would allow Trump to redirect federal funds from elsewhere to pay for his border wall. 

Jessica Levinson, political law professor at Loyola Law School, said although Trump had the power to declare an emergency at any moment, it would be a complicated process.

“He has to say here’s an emergency and here’s what I need,” she told Al Jazeera.

“I need more money, I need more people, etc,” she added. “But the question is then if he waited so long to do this, and the country went through a government shutdown over this, how is it an emergency now? Where is the urgency?”

It’s also unclear where Trump can get the funding because Congress would still need to earmark money for the wall. However, some legal experts have told local media that Trump may be able to turn to unallocated funds in the Department of Defense’s budget. 

A source told Reuters that the White House lawyers had vetted the figures and believed they would withstand a legal challenge.

Levinson said to expect a legal battle once Trump declares a national emergency. 

“At that point, people will sue and say this is not an emergency,” she said.

Under the Constitution, Congress holds the national purse strings and makes major decisions on spending taxpayer money.

Disputes over the constitutionality or legality of the exercise of emergency powers are judicially reviewable, the document prepared for Congress states.

What does Trump say?

Trump, who campaigned on a promise to build a wall on the US-Mexico border, had demanded Congress allocate $5.7bn in funding for the wall. 

But Democrats, who recently took control of the House of Representatives, refused, calling the wall ineffective, expensive and immoral. 

The legislation hammered out by Congress this week does not include money for a concrete wall, but it does allocate $1.37bn in funding for physical barriers. 

But Trump hopes with the national emergency he can still follow through on his campaign promise. 

On Monday, as congressional leaders announced a compromise that didn’t include wall funding, Trump declared in front of a rally of supporters that he was going to get the wall built one way or the other. 

“Just so you know – we’re building the wall anyway,” Trump said. 

The president maintains that the wall is necessary to stem irregular immigration and drug trafficking. 

But statistics show that irregular immigration has dropped to a 20-year low and that many drug shipments are likely smuggled through official ports of entry, leading critics to argue a wall is not needed. 

What do Democrats say?

Democrats have long resisted Trump’s call for a wall.

House Speaker Nancy Pelosi said on Thursday that there was no crisis at the border with Mexico that requires a national emergency order. 

“If the president can declare an emergency on something that he has created as an emergency – an illusion that he wants to convey – just think of what a president with different values can present to the American people,” Pelosi added, pointing to gun violence in the United States as a national emergency.

She said Democrats were prepared to respond appropriately to a declaration of national emergency. 

She has not said if House Democrats would legally challenge the president. But she did say if Trump invoked an emergency declaration it should be met with “great unease and dismay” as an overreach of executive authority. 

She added that such a declaration would mean Trump was making an “end run around Congress”. 

The top Democrat in the Senate echoed Pelosi’s harsh comments. 

Senator Chuck Schumer said if Trump declared a national emergency to build the wall, he would be committing a “lawless act”. He also warned that Congress would take steps to stop the president. 

He added that Trump would be committing “naked contempt for the rule of law and congressional authority”.