The U.S. Supreme Court ruled on Friday that President Donald Trump's sweeping global tariffs, imposed under a law designed for national emergencies, were illegal – a landmark decision that immediately reignited political tensions and economic uncertainty.

In a 6–3 ruling, the Court held that Trump's use of the International Emergency Economic Powers Act (IEEPA) to levy tariffs on imports from nearly all U.S. trading partners was unconstitutional. The majority concluded that IEEPA does not grant the president authority to impose broad import taxes, reaffirming that the Constitution gives Congress – not the executive branch – the power to levy taxes.

Chief Justice John Roberts delivered the opinion of the court, saying the president must "point to clear congressional authorization" to justify his extraordinary assertion of the power to impose tariffs. The Court found that the administration's interpretation of IEEPA violated the "major questions" doctrine, which requires explicit congressional approval for sweeping executive actions.

Justices Clarence Thomas, Samuel Alito and Brett Kavanaugh dissented in the vote.

Trump responds with new tariff order

Trump denounced the ruling, accusing the majority of yielding to foreign influence and calling them "unpatriotic and disloyal" to the Constitution. Within hours, he had signed a new executive order imposing a 10-percent "global tariff" under Section 122 of the Trade Act of 1974.

"It is my Great Honor to have just signed, from the Oval Office, a Global 10% Tariff on all Countries, which will be effective almost immediately," Trump wrote on Truth Social.

Trump is the first U.S. president to invoke Section 122, which allows the president to levy tariffs of up to 15 percent for a maximum of 150 days to fix "fundamental international payments problems." Any extension beyond that would require congressional approval, and legal challenges are widely expected.

In an executive order, the White House confirmed that the additional IEEPA tariffs will "no longer be in effect" and will cease to be collected "as soon as practicable." The new 10 percent tariff will take effect at 12:01 a.m. Eastern Standard Time on February 24 (5:01 a.m. GMT) and remain in place for 150 days.

The shift could result in lower tariff rates for some countries that had negotiated trade deals with Washington. The European Union, for example, had agreed to a 15-percent tariff rate under a separate trade arrangement – meaning the new 10 percent tariff would mark a reduction.

Domestic and international reactions

The ruling was welcomed by business groups and foreign governments alike, while Democrats launched a stinging attack on Trump. 

The National Retail Federation said the decision provides "much-needed certainty" for businesses and manufacturers, allowing global supply chains to function without ambiguity. The Footwear Distributors and Retailers of America likewise welcomed it, calling the outcome an important step toward restoring predictability for American companies and consumers.

California Governor Gavin Newsom demanded that the administration refund, with interest, tariffs collected under the invalidated policy. "Time to pay the piper, Donald," Newsom said in a statement, calling the tariffs "an illegal cash grab" that raised prices and hurt working families. "Every dollar unlawfully taken must be refunded immediately – with interest."

Internationally, reactions were largely positive. Bernd Lange, chair of the European Parliament's Committee on International Trade, said the ruling sent a positive signal for the rule of law, demonstrating that "even the U.S. president is not above the law." He suggested that the era of "unrestricted and arbitrary tariff hikes" may be coming to an end.

Canada also welcomed the decision. Trade Minister Dominic LeBlanc said the finding reinforced Ottawa's long-held view that Washington's use of IEEPA to justify tariffs was unfounded. However, he acknowledged ongoing challenges, particularly in supporting Canada's steel, aluminum and auto sectors affected by U.S. trade measures.

Economic uncertainty persists

Market relief was short-lived, as economists and investors cautioned that uncertainty remains high. After a year of often ad hoc tariff announcements that rattled markets and disrupted global supply chains, Friday's decision – and Trump's swift countermeasure – reintroduced volatility.

"I think it will just bring in a new period of high uncertainty in world trade, as everybody tries to figure out what the U.S. tariff policy will be going forward," said Varg Folkman, analyst at the European Policy Centre think tank.

Treasury Secretary Scott Bessent suggested the impact would be mixed. Speaking to Fox News, he said the Court had reduced the president's leverage in one sense but confirmed he still retains authority to impose broader trade restrictions, including a potential full embargo.

"We will get back to the same tariff level for the countries. It will just be in a less direct and slightly more convoluted manner," he said.

The ruling did not address whether tariffs already paid under the higher rates will be refunded – a question likely to trigger further litigation.

U.S. Customs and Border Protection reported collecting more than 200 billion U.S. dollars in tariffs between January 20 and December 15, 2025. Of that amount, the administration said roughly $129 billion stemmed specifically from IEEPA-related duties.

Meanwhile, a recent Federal Reserve Bank of New York report found that nearly 90 percent of the tariff burden in 2025 was borne by U.S. consumers and businesses, contradicting claims that foreign exporters were paying the bulk of the costs.

Timeline of the legal battle

Trump first announced on April 2 that the United States would impose a minimum 10-percent baseline tariff on nearly all imported goods, with higher rates targeting specific trading partners. He argued the measures would raise government revenue and revive domestic manufacturing.

On April 23, a coalition of 12 states filed suit in the U.S. Court of International Trade in New York, challenging the legality of the tariffs. The court ruled against the administration, and a federal appeals court upheld that decision on August 29, finding that Trump had improperly invoked IEEPA.

The administration appealed to the Supreme Court in September. Friday's ruling marks the final judicial blow to the IEEPA-based tariff regime, though the broader legal and economic fallout is far from settled.

(With input from agencies)