JOHN YOO: Supreme Court tariff ruling should end complaints that justices favor Trump

Supreme Court strikes down Trump's worldwide tariffs in 6-3 Learning Resources decision, with liberal justices and some conservatives ruling against IEEPA.

The government, and the lower courts, have long understood the power to "regulate" trade to include the power to impose a complete embargo on hostile nations, such as Cuba, Iran and North Korea. John Yoo is Heller Professor of Law at the University of California, Berkeley; distinguished visiting scholar at the School of Civic Leadership and a senior research fellow at the Civitas Institute at the University of Texas at Austin; and a nonresident senior fellow at the American Enterprise Institute.

Where the justices divided is whether Congress had given the president the power to impose the unique, worldwide, immediate tariffs that he imposed last year. On Liberation Day, April 2025, Trump invoked the International Emergency Economic Powers Act of 1977 (IEEPA) to set targeted tariffs not only on Canada, Mexico and China, but also a universal tariff of at least 10% on all imports. Roberts, joined by a rare coalition of three conservative justices (himself, Justices Neil Gorsuch and Amy Coney Barrett) and three liberal justices (Justices Sonia Sotomayor, Elena Kagan, and Ketanji Brown Jackson), held that IEEPA did not grant the executive the power to impose tariffs.

The majority unduly narrowed the reach of IEEPA. IEEPA grants the power to the president, in the event of an "unusual and extraordinary threat" to American national security, foreign policy or the economy from abroad, to investigate, block, "regulate, direct and compel, nullify, void, prevent or prohibit" economic transactions with another country.