SACRAMENTO (KPIX 5) — Not long after President Trump announced his plan to take nearly $7 billion of federal money and direct it toward building more border barriers, California officials were already set to file a lawsuit in opposition.

“Donald Trump, we’ll see you in court,” said California Governor Gavin Newsom at a press conference Friday with state Attorney General Xavier Becerra.

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At the conference, Becerra announced that the state will file lawsuit number 46 against the Trump Administration in an effort to stop the President’s efforts at shoring up more money for border barriers.

Neither Newsom nor Becerra had read or analyzed the President’s declaration at the time of the conference, but Newsom assured assembled journalists that Becerra’s office had been preparing for this day and would file a lawsuit very soon.

The President’s Emergency Declaration Friday was necessary to access $3.6 billion in funds for more border barriers. Another $3.1 billion needs no emergency declaration.

The President’s Emergency Declaration is based on his assertion that, “The southern border is a major entry point for criminals, gang members, and illicit narcotics…[and] recent years have seen sharp increases in the number of family units entering and seeking entry to the United States and an inability to provide detention space for many of these aliens while their removal proceedings are pending.”

“He has the power to declare a national emergency,” California Attorney General Becerra acknowledged. “But this is not 9/11, this is not the Iran hostage crisis of 1979.”

But the law invoked by the President, the National Emergencies Act (50 U.S.C. Ch. 34) does not define a “national emergency.” A court could defer completely to the President’s judgment on that definition or try to draw some contours around the phrase; either way, this is unchartered territory.

The law requiring an Emergency Declaration is a military construction law passed in 1982 with bipartisan support (10 U.S.C. 2808). This law only operates during a national emergency.

It states, “In the event of a declaration of war or the declaration by the President of a national emergency in accordance with the National Emergencies Act (50 U.S.C. 1601 et seq.) that requires use of the armed forces, the Secretary of Defense, without regard to any other provision of law, may undertake military construction projects…”

Note that this law does not set forth a process for determining what “requires the use of the armed forces” and appears to give that authority to the Secretary of Defense. It basically defines “military construction projects” as any construction under the jurisdiction of the Secretary of Defense. (10 U.S.C. 2801)

In other words, from “What is a national emergency?” to “What is a military construction project?” there are important questions for the courts.

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If the “Emergency Declaration” is found to be invalid, the military construction route would be closed, but two other options would remain open.

First, the White House indicates it will get $2.5 billion for border barriers from an anti-drug trafficking law passed in 2016 with bipartisan support. (10 U.S.C. 284) In fact, House Speaker Nancy Pelosi and California Senator Dianne Feinstein voted in favor of this law.

It states, “The Secretary of Defense may provide support for the counter-drug activities or activities to counter transnational organized crime of any other department or agency of the Federal Government…” including “Construction of roads and fences and installation of lighting to block drug smuggling corridors across international boundaries of the United States.”

This law does not define “counter-drug activities” or “drug smuggling corridors.” The courts will have to grapple with those questions.

Second, the President expects to get $601 million from law that governs how we spend “asset forfeitures” — the money and property we take from criminals (31 U.S.C. 9705). It was passed in 1992 with bipartisan support in the Senate, but the House of Representatives was a different story.

In the House, Democrats — including House Speaker Nancy Pelosi — voted in favor of this law by a vote of 232 in favor and 23 against. Republicans did not endorse the law, voting 59 in favor and 103 against.

This law requires the money from asset forfeitures to be spent on certain items, but the Treasury Secretary can transfer any extra money to “law enforcement activities of any Federal agency…”

When congress passed these laws with undefined terms and large leeway for the Executive (which includes the Secretaries of the Treasury and Defense) they likely never contemplated Donald Trump.

“You’re always legislating based on the history you know, not the future that you don’t know and here we are really in a future we didn’t anticipate,” said Hastings Law Professor Rory Little. “Would congress today write a lot more constraints into this emergency law? Absolutely.”

Over the last several decades, the Legislative branch has repeatedly given power to the Executive branch by passing laws like the ones now relied on by the President.

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“You might see a legislative reaction to this presidency to further constrain the executive,” said Professor Little. “But you know, not if a Democrat gets in office, right?”