President Donald Trump's declaration of a national emergency to unlock funds for a border wall was challenged in court within hours by three Texas land owners and an environmental group, the first of several lawsuits expected as civil rights groups and Democrats vowed to mount legal and legislative challenges against what they called an act of presidential overreach.
The land owners, who had been informed that the government intended to build a wall on their property, said their privacy and quiet enjoyment of their land would be affected, while the nature group said wall construction would destroy habitats and impair wildlife observation, according to the lawsuit filed on their behalf by consumer rights group Public Citizen.
The American Civil Liberties Union and the state of California also vowed to fight Mr Trump's emergency declaration, and attorneys-general in Colorado, Nevada, New Mexico and New York are expected to mount legal challenges as well against Mr Trump's efforts to bypass Congress.
"If the President tries to use a made-up emergency to pay for his border wall, then California will see him in court," California Governor Gavin Newsom and attorney-general Xavier Becerra, both Democrats, said in a joint statement.
Mr Trump said on Friday that he was confident his emergency declaration to unlock funds for his border wall would stand up in the Supreme Court, justifying the move as a matter of national security needed to secure the US-Mexico border against what he called "an invasion of drugs... of gangs".
He acknowledged that he might lose in the lower courts but was hopeful that his policy would be upheld by the Supreme Court, a process his administration went through last year over its travel ban targeting people from several Muslim-majority countries.
The emergency declaration was the first step to securing up to US$3.6 billion (S$4.8 billion) reallocated from military construction projects, after Congress granted the President US$1.375 billion for 90km of fencing, only a quarter of the US$5.7 billion he had asked for.
House Speaker Nancy Pelosi and Senate Minority Leader Chuck Schumer said in a joint statement on Friday that Mr Trump's actions violated the Congress' exclusive power to allocate federal funds as enshrined in the Constitution, calling it "a power grab by a disappointed President".
"The Congress will defend our constitutional authorities in the Congress, in the courts, and in the public, using every remedy available," they added.
The White House defended the legality of the move, which acting chief of staff Mick Mulvaney told reporters was due to Congress "being simply incapable of providing the amount of money necessary, in the President's eyes, to address the current situation at the border".
Office of Management and Budget acting director Russell Vought said it was common authority to be able to declare a national emergency and presidents had done so 58 times since the National Emergencies Act was enacted in 1976.
Constitutional law experts, however, argued that Mr Trump's declaration this time was a fairly unprecedented use of that authority.
Georgetown University law professor Mary McCord said many emergency declarations were responses to crises in other countries and generally had to do with blocking property, access to funds, and prohibiting financial transactions with designated persons or entities who presented threats to the US due to terrorism, espionage and other matters. "That doesn't seem to exist at all with respect to this declaration of national emergency," she told reporters in a briefing call organised by the American Constitution Society.
Ohio State University law professor Peter Shane, who specialises in separation of powers, said national emergencies typically resulted in immediate responses, adding that he could think of no other case in which a president declared a national emergency directing other agencies to engage in a multi-year construction project in response to an exigency.
Q & A
1. Q What is a national emergency?
A In 1976, Congress passed the National Emergencies Act, which permits the president to pronounce a national emergency when he considers it appropriate.
The Act offers no specific definition of "emergency" and allows a president to declare one entirely at his discretion.
By declaring a national emergency, the president avails himself of dozens of specialised laws. Some of these powers have funds the president could otherwise not access.
Under current law, emergency powers lapse within a year unless the president renews them.
A national emergency can be redeclared indefinitely and, in practice, that is done frequently. There have been 58 pronounced under the National Emergencies Act, of which 31 are still in effect.
2. Q What happens once a national emergency has been declared?
A Even though there are not many limits on a president's ability to declare an emergency, it does not create carte blanche freedom to act.
Anyone directly affected by the order can challenge it in court, which Ms Elizabeth Goitein - co-director of the Brennan Centre for Justice's Liberty and National Security Programme - said will almost certainly happen in this case.
Congress can also draft a concurrent resolution to terminate the state of emergency, leading to a somewhat novel act.
Ordinarily, congressional resolutions support a president's declaration of a national emergency.
Democratic House Speaker Nancy Pelosi is expected to bring up a "joint resolution of termination" in the House. Doing so would force Republican Senate Majority Leader Mitch McConnell to also bring up the resolution in the Republican-majority Senate, putting his members in a difficult position. The House Democrats can also join an outside lawsuit or choose to sue on their own.
3. Q Does Congress have enough votes to terminate the emergency declaration?
A Like any legislation passed by Congress, the president could veto the resolution unless it has received supermajority support (two-thirds in each chamber).
Many Republicans have been critical of this approach by President Donald Trump, mainly because they see it as a slippery slope for a future Democratic president using the power to advance his policy goals. But it is unclear whether there are enough of them to vote against the president (and his base) to override a veto.