Express and Inherent Presidential Powers: There are four approaches based upon the court case Youngstown Sheet & Tube Co. v. Sawyer, 343 U.S. 579, 634 (1952):
1) There is no inherent presidential power; the president may act only if there is express constitutional or statutory authority.
2) The president has inherent authority unless the president interferes with the functioning of another branch of government or usurps the powers of another branch.
3) The president may exercise powers not mentioned in the Constitution so long as the president does not violate a statute or the Constitution.
4) The president has inherent powers that may not be restricted by Congress and may act unless the Constitution is violated (Chemerinsky 331).
“The federal courts and ultimately the Supreme Court should quickly and emphatically hold that President Trump’s attempt to fund the border wall by declaring a national emergency is illegal and unconstitutional. In 1974, when President Richard Nixon made an unprecedented claim of executive power to resist complying with a subpoena from the Watergate special prosecutor, the Supreme Court unanimously rejected this assertion and enforced constitutional checks and balances. We should hope and expect that even the conservative Roberts Court, with two justices appointed by President Trump, will likewise follow the Constitution and reject Trump’s dangerous claim of emergency powers.
“The Constitution has no clause that gives the president emergency powers. This was a deliberate and wise choice. The framers of the Constitution wanted to make sure that its requirements, including checks and balances, are enforced even in times of crisis. Indeed, when prior presidents have tried to claim inherent power to deal with emergencies, the Supreme Court has rejected such claims.
“During the Korean War, President Harry Truman seized the steel mills to assure continued steel production in the face of a labor dispute. The Supreme Court, in (1952), decisively ruled against President Truman and rejected his claimed authority to take actions to deal with a national emergency. The Court stressed that Truman’s actions violated the separation of powers and usurped the powers of Congress.
“Likewise, The Constitution reads, ‘No Money shall be drawn from the Treasury, but in Consequence of Appropriations made by Law.’ Under the Constitution, Congress has the power of the purse and it is impermissible for the president to spend money without specific statutory authorization.
“No such authorization exists for building the border wall. Trump repeatedly has urged Congress to provide such funds. Even when Republicans controlled both houses of Congress, from 2017 to 2019, Trump could not get this authorization. More recently, the government shut down for a month because Congress would not appropriate the funds Trump wanted to build the wall. For Trump to fund the wall unilaterally without congressional approval, even by claiming a national emergency, is clearly unconstitutional.
“Trump likely will claim the authority to fund building the wall under the National Emergencies Act of 1976. One provision says that if there is a national emergency, funds in the Defense Department budget that are not ‘obligated’ can be used for construction projects to support the armed forces. It reads: ‘Secretary of Defense, without regard to any other provision of law, may undertake military construction projects, and may authorize Secretaries of the military departments to undertake military construction projects that are necessary to support such use of the armed forces.’ The statute is about construction projects to support the armed forces. Trump’s wall is not about that at all.
“Members of Congress have standing to sue President Trump for violating the separation of powers and nullifying the spending power possessed by Congress. In 2016, U.S. District Court Judge Rosemary Collyer held that members of the Republican-controlled Congress had legal standing to sue the president to challenge the spending of federal funds without specific federal authorization. She held that the Obama administration was violating the Constitution by paying, without a congressional appropriation, the promised reimbursements to health insurers who provide coverage at reduced costs to low-income Americans. ‘Paying [those] reimbursements without an appropriation thus violates the Constitution,’ she wrote. ‘Congress is the only source for such an appropriation, and no public money can be spent without one.’
“At the time, Republican House Speaker Paul Ryan called the ruling ‘a historic win for the Constitution and the American people. The court ruled that the administration overreached by spending taxpayer money without approval from the people's representatives.’
“Members of Congress should now sue President Trump—and should prevail in court. No court should accept President Trump’s claim of a ‘national emergency.’ Trump has been calling for the wall for years. The claim of ‘national emergency’ is a pretext to allow the president to do whatever he wants.
“If my prediction is wrong and Trump wins in court, Democratic presidential candidates should prepare their own wish lists of what can be done without congressional approval. A Democratic president could follow the Trump example and declare a national emergency to deal with the problem of climate change—a genuine emergency.
“But whether we have a Democratic or Republican president, and no matter how noble the cause, we should be frightened of presidents acting unilaterally to deal with a national emergency. That would completely undermine the checks and balances and the separation of powers that are at the core of our constitutional system of government. Until and unless Congress authorizes funds for the border wall, it is unconstitutional and illegal for President Trump to use any other funds for this purpose” (Trump’s ‘Emergency’ Action: Unlawful and Unconstitutional).
Chemerinsky, Erwin. Constitutional Law: Principles and Policies, 2nd ed. New York: Aspen Publishers, 2002.
Chemerinsky, Erwin. “Trump’s ‘Emergency’ Action: Unlawful and Unconstitutional.” The American Prospect, 15 February 2019 https://prospect.org/article/trumps-emergency-action-unlawful-and-unconstitutional