On February 1, 2025, President Donald Trump issued three executive orders imposing tariffs—of varying levels—on imports from Mexico, Canada, and China. On April 2, 2025, President Trump broadened the scope of tariffs to include the entire globe, imposing a 10 percent tariff on all U.S. trading partners and “reciprocal tariffs” of up to 50 percent on almost 90 specific companies. The legal authority the President relied on to impose the tariffs is the International Emergency Economic Powers Act (IEEPA), a statute that becomes available when the president declares a national emergency under the National Emergencies Act (NEA). IEEPA authorizes presidents to impose economic sanctions and regulate economic transactions during national emergencies that involve an “unusual and extraordinary threat” to the U.S. national security, foreign policy, or economy.
Various corporations and state governments responded to President Trump’s tariffs by filing lawsuits in federal courts across the country. In September 2025, the Supreme Court agreed to hear two of those cases, Learning Resources v. Trump and Trump v. V.O.S. Selections.
The Brennan Center filed a friend-of-the-court brief in several of the cases. Drawing on our extensive research on presidential emergency powers, the brief argues that Congress enacted both the NEA and IEEPA to rein in the presidential use of emergency powers and to ensure they could not be used to displace non-emergency laws.
On February 20, 2026, the Supreme Court ruled that IEEPA does not authorize the President to impose tariffs.
Briefs filed by the Brennan Center in the IEEPA tariff litigation:
- Emily Ley Paper, Inc. v. Trump (U.S. District Court for the Northern District of Florida)
- State of California v. Trump (U.S. District Court for the Northern District of California)
- State of California v. Trump (U.S. Court of Appeals for the Ninth Circuit)
- V.O.S. Selections, Inc. v. Trump (U.S. Court of Appeals for the Federal Circuit)
- Learning Resources, Inc. v. Trump (U.S. Court of Appeals for the District of Columbia Circuit)
- Learning Resources, Inc. v. Trump (U.S. Supreme Court)
