WASHINGTON (AP) — The Supreme Court struck down President Donald Trump’s far-reaching global tariffs on Friday, handing him a significant loss on an issue crucial to his economic agenda.

The decision centers on tariffs imposed under an emergency powers law, including the sweeping “reciprocal” tariffs he levied on nearly every other country.

It’s the first major piece of Trump’s broad agenda to come squarely before the nation’s highest court, which he helped shape with the appointments of three conservative jurists in his first term.

The Republican president has been vocal about the case, calling it one of the most important in U.S. history and saying a ruling against him would be an economic body blow to the country. But legal opposition crossed the political spectrum, including libertarian and pro-business groups that are typically aligned with the GOP. Polling has found tariffs aren’t broadly popular with the public, amid wider voter concern about affordability.

The Supreme Court ruling comes despite a series of short-term wins on the court’s emergency docket that have allowed Trump to push ahead with extraordinary flexes of executive power on issues ranging from high-profile firings to major federal funding cuts.

The tariffs decision doesn’t stop Trump from imposing duties under other laws. While those have more limitations on the speed and severity of Trump’s actions, top administration officials have said they expect to keep the tariff framework in place under other authorities.

The Constitution gives Congress the power to levy tariffs. But the Trump administration argued that a 1977 law allowing the president to regulate importation during emergencies also allows him to set tariffs. Other presidents have used the law dozens of times, often to impose sanctions, but Trump was the first president to invoke it for import taxes.

Trump set what he called “reciprocal” tariffs on most countries in April 2025 to address trade deficits that he declared a national emergency. Those came after he imposed duties on Canada, China and Mexico, ostensibly to address a drug trafficking emergency.

A series of lawsuits followed, including a case from a dozen largely Democratic-leaning states and others from small businesses selling everything from plumbing supplies to educational toys to women’s cycling apparel.

The challengers argued the emergency powers law doesn’t even mention tariffs and Trump’s use of it fails several legal tests, including one that doomed then-President Joe Biden’s $500 billion student loan forgiveness program.

The economic impact of Trump’s tariffs has been estimated at some $3 trillion over the next decade, according to the Congressional Budget Office. The Treasury has collected more than $133 billion from the import taxes the president has imposed under the emergency powers law, federal data from December shows. Many companies, including the big-box warehouse chain Costco, have already lined up in court to demand refunds.