“Trump unilaterally imposed tariffs on much of the world. Yet the president has no such authority under Article II of the Constitution, which enumerates the limited powers of the executive branch. Instead, the authority “to lay and collect Taxes, Duties, Imposts and Excises,” as well as the authority “to regulate Commerce with Foreign nations,” resides exclusively in Article I, which is where the limited powers of the legislative branch are detailed.
So, Trump’s trade war violates the constitutional separation of powers because Trump has unlawfully exercised power that the Constitution placed in the hands of Congress, not in the hands of the president.”
…
“As a pretext for his trade war, Trump invoked the International Emergency Economic Powers Act (IEEPA). Yet “the statute is silent on tariffs, and for good reason. It was never meant, and has never been understood, to authorize the President to impose them.” That observation comes from a superb friend of the court brief filed by a cross-ideological group of legal scholars and former government officials in support of the legal challenge against Trump’s tariffs. Their brief thoroughly explains why Trump’s use of the IEEPA to fundamentally remake the American economy cannot be reconciled with any law passed by Congress. In short, Trump’s tariffs flunk the test imposed by the major questions doctrine.”
https://reason.com/2025/06/05/overruling-trumps-tariffs-should-be-an-easy-decision-for-scotus