The IEEPA Tariff Litigation

When the Trump administration invoked IEEPA to impose sweeping global tariffs in 2025, importers and states quickly challenged the actions in federal court, setting off one of the most significant trade law litigation battles in modern U.S. history.

Initial Challenges: The Court of International Trade

The first challenges to the IEEPA tariffs were filed in the U.S. Court of International Trade (CIT), the specialized federal court with exclusive jurisdiction over customs and trade law matters. Multiple importers and trade associations argued that:

• IEEPA's text does not authorize tariffs

• Even if it did, the delegation of such broad authority to the President is unconstitutional

• The declared national emergencies (trade deficits, immigration, and drug trafficking) did not qualify as the kind of "unusual and extraordinary" threats contemplated by the statute

In May 2025, the CIT issued a permanent injunction against the IEEPA tariffs, concluding that the statute's language authorizing the president to "regulate . . . importation" cannot be read to authorize the imposition of tariffs.

The Federal Circuit Appeals

The Trump administration immediately appealed to the U.S. Court of Appeals for the Federal Circuit (CAFC), which has appellate jurisdiction over CIT decisions. In May 2025, the CAFC stayed the CIT's injunction pending appeal, allowing the tariffs to remain in effect while the case was reviewed.

In September 2025, the CAFC issued its full merits ruling, affirming the CIT's decision that the IEEPA tariffs exceeded presidential authority. The court applied the major questions doctrine, holding that IEEPA's language does not clearly authorize the President to impose unlimited tariffs of unlimited duration on all trading partners. The CAFC stayed its own order to allow the government to seek Supreme Court review.

Parallel District Court Litigation

Simultaneously, a separate group of plaintiffs — including a coalition of small businesses and several state attorneys general — filed suit in the U.S. District Court for the District of Columbia. The D.C. court also ruled against the tariffs, finding that IEEPA does not authorize tariffs of any sort.

The government appealed the D.C. Circuit decision, but before arguments could be heard in that case, the Supreme Court granted certiorari and consolidated the cases.

Standing Issues

Throughout the litigation, the government argued that many plaintiffs lacked standing to challenge the tariffs and that jurisdiction was lacking because IEEPA does not authorize tariffs. The CIT, in a December 15, 2025 decision, confirmed that it "has the explicit power to order reliquidation and refunds" of IEEPA duties, establishing the court's authority to provide monetary relief to successful challengers.

Key Legal Arguments

The main legal debates centered on three issues:

1. Statutory Interpretation: Does IEEPA's language authorizing the President to "regulate . . . importation" encompass the imposition of tariffs? The government argued yes, pointing to the broad definition of "regulate" and historical precedents. Challengers argued no, noting that Congress has used precise language when granting tariff authority elsewhere in the code.

2. The Major Questions Doctrine: Even if IEEPA could be read to authorize tariffs, does the political and economic magnitude of unlimited global tariffs require a clear statement from Congress? The challengers prevailed on this argument at the Supreme Court.

3. The Nondelegation Doctrine: Does granting the President unlimited tariff authority without any stated limits violate the constitutional requirement that Congress provide an intelligible principle to guide executive action? The Supreme Court did not need to reach this question once it resolved the case on statutory grounds.

The Supreme Court's Intervention

The Supreme Court granted expedited review in late 2025, hearing oral arguments on November 5, 2025. On February 20, 2026, the Court issued its landmark ruling in Learning Resources, Inc. v. Trump, 607 U.S. ___ (2026), holding 6–3 that IEEPA does not authorize the President to impose tariffs.