WASHINGTON – The Supreme Court on Friday delivered a significant blow to the Trump administration, ruling that former President Trump did not have the authority to unilaterally impose sweeping tariffs on nearly every country under the International Emergency Economic Powers Act (IEEPA). The 6-3 decision upholds a lower court ruling that found Mr. Trump’s tariffs were illegal.
The court held that IEEPA, a 1977 law intended to grant the president authority to regulate international transactions during a national emergency, does not authorize the imposition of tariffs. Chief Justice John Roberts wrote the majority opinion, with Justices Clarence Thomas, Samuel Alito, and Brett Kavanaugh dissenting, according to NBC News.
“The Government reads IEEPA to give the President power to unilaterally impose unbounded tariffs and change them at will,” Chief Justice Roberts wrote. “That view would represent a transformative expansion of the President’s authority over tariff policy.” The court noted the lack of historical precedent for using IEEPA to impose tariffs, stating that no president had done so in the law’s half-century of existence.
The legal battle marked the first time the Supreme Court evaluated the legal merits of a second-term policy enacted during the Trump presidency. While the court had previously allowed the administration to temporarily enforce its plans while legal proceedings were underway, this ruling represents the most substantial legal defeat for Mr. Trump thus far in his second term, CBS News reported.
The decision does not preclude the president from imposing tariffs under other trade authorities. Mr. Trump had already utilized other laws to levy tariffs on imports of copper, steel, and aluminum, as well as other products. According to the CNBC, the average effective tariff rate is currently near 17%, the highest since the early 1930s.
The ruling comes as the Supreme Court similarly considers other significant cases involving the Trump administration, including challenges to the president’s authority to fire officials at independent federal agencies and the legality of his plan to end birthright citizenship. Arguments in the birthright citizenship case are scheduled for April.
The decision arrives amid concerns about the US economic outlook. Recent data shows that US economic growth slowed sharply in the fourth quarter of 2025, increasing at an annual rate of 1.4%, according to the US Bureau of Economic Analysis. This represents a significant decrease from the 4.4% growth experienced in the third quarter of last year.
Donald Trump is currently in Washington, hosting a working breakfast for several US governors. The National Governors Association (NGA) initially limited invitations to Republican governors, but Mr. Trump claimed the NGA chair, Governor Kevin Stitt of Oklahoma, had “incorrectly stated” his position, and that he had invited all governors except those from Maryland and Colorado, whom he has publicly feuded with.
The Trump administration also announced Friday it will roll back air regulations for power plants, limiting mercury and hazardous air toxics. The move, announced in Kentucky, is intended to boost baseload energy but has drawn criticism from public health groups who argue it will harm vulnerable populations.
