A federal trade court issued a major ruling against the Trump administration Wednesday declaring that President Trump may not unilaterally impose tariffs with an emergency law.

The Court of International Trade struck down Trump’s wide-ranging “liberation day” tariffs enacted last month and other tariffs he placed earlier in his term, a blow to one of the central pillars of Trump’s policy agenda as he attempts to use tariffs as leverage in various negotiations.

“The question in the two cases before the court is whether the International Emergency Economic Powers Act of 1977 (‘IEEPA’) delegates these powers to the President in the form of authority to impose unlimited tariffs on goods from nearly every country in the world. The court does not read IEEPA to confer such unbounded authority and sets aside the challenged tariffs imposed thereunder,” the court said.

The Trump administration attempted to use the International Emergency Economic Powers Act of 1977 to place tariffs on China, Mexico, Canada, and numerous other countries globally on a wide range of everyday goods. Trump’s tariff announcements began in February, and the federal court categorized them based on their scope and justification.

Before the Trump administration, the IEEPA had never been used to authorize tariffs through presidential action. The IEEPA allows the president to take emergency action on foreign threats to the U.S., including sanctions and asset freezes, but says nothing on tariffs specifically. While Trump has used tariffs to pursue his national security and trade objectives, most economists say that tariffs function as a domestic tax on business and consumers purchasing imports from abroad.

“The court holds for the foregoing reasons that IEEPA does not authorize any of the Worldwide, Retaliatory, or Trafficking Tariff Orders. The Worldwide and Retaliatory Tariff Orders exceed any authority granted to the President by IEEPA to regulate importation by means of tariffs. The Trafficking Tariffs fail because they do not deal with the threats set forth in those orders,” the New York–based court added.

“The challenged Tariff Orders will be vacated and their operation permanently enjoined.”

The three-judge panel granted summary judgement in two separate cases, the first brought by several companies affected by the tariffs and the second a lawsuit from a collection of states. The two groups of plaintiffs sued the administration over the constitutionality of Trump’s ability to use the IEEPA to enact tariffs.

Beyond those cases, the Court of International Trade’s decision could affect similar tariff-related cases in front of it and other federal courts. The federal government is expected to appeal the court’s ruling immediately.

“The judicial coup is out of control,” Trump policy advisor Stephen Miller posted on X, reacting to the decision. The Trump administration and its allies have routinely criticized federal judges for perceived overreach in their rulings against the president’s executive actions.

The Court of International Trade judges ruling on the case were appointed by Presidents Reagan, Obama, and Trump respectively. Trump-appointed judge Timothy Reif identifies politically as a Democrat and was appointed under court rules requiring political balance.

Under Article I of the Constitution, Congress has the ability to control tax policy, but the legislative branch has largely ceded its tariff authority to the presidency in recent decades. Some conservatives have urged Congress to reclaim its constitutional authority on tariffs, given Trump’s enthusiasm for them and significant bipartisan opposition to his tariff policy.

Trump and his officials have said 78 countries have sought to negotiate trade deals following his sweeping “liberation day” tariff package that rattled global markets and businesses. Following widespread panic on Wall Street over the tariffs, Trump announced a 90 day pause on them as negotiations unfold.