In a major blow to President Donald Trump’s economic agenda, the US Supreme Court on Friday invalidated most of his sweeping tariffs, ruling that he lacked authority under a 1977 emergency law to impose broad import levies on America’s trading partners worldwide, including India.

The 6-3 ruling, described by Politico as “a major repudiation of a core piece of Trump’s economic programme,” limits the president’s ability to use executive power unilaterally in trade matters.

Chief Justice John Roberts, writing for the majority, stated:

“The President asserts the extraordinary power to unilaterally impose tariffs of unlimited amount, duration, and scope. In light of the breadth, history, and constitutional context of that asserted authority, he must identify clear congressional authorization to exercise it.”

Roberts noted that the 1977 law Trump relied on, the International Emergency Economic Powers Act (IEEPA), “falls short” of the congressional approval required. The court emphasized that IEEPA was intended to regulate imports only to address national emergencies posing unusual and extraordinary threats, not to impose broad tariffs.

Trump had invoked emergencies over fentanyl and trade deficits to justify tariffs on countries including Canada, China, Mexico, and others, imposing what he called reciprocal tariffs. India faced an 18 percent tariff. The Hill highlighted that Trump is the first president in IEEPA’s nearly 50-year history to attempt using it for tariffs.

Some sector-specific tariffs, such as those on steel, aluminium, and copper, which rely on separate legal authorities, remain in effect.

The ruling is expected to trigger lawsuits as companies seek to recover billions of dollars in tariffs already paid. Costco, Toyota, Revlon, and hundreds of others had filed suits to protect their claims.

While the decision marks a significant defeat for Trump, Congress still retains the authority to impose tariffs, and the administration could seek other legal avenues to justify duties.

Enacted in 1977, IEEPA primarily allowed presidents to impose sanctions during national emergencies, making this case a landmark test of executive power in trade policy.