A federal appeals court ruled on Friday that many of President Trump’s most punishing tariffs were illegal, delivering a major setback to Mr. Trump’s agenda that may severely undercut his primary source of leverage in an expanding global trade war. The ruling, from the U.S. Court of Appeals for the Federal Circuit, affirmed a lower court’s initial finding in May that Mr. Trump did not possess unlimited authority to impose taxes on nearly all imports to the United States. But the appellate judges delayed the enforcement of their order until mid-October, allowing the tariffs to remain in place so that the administration can appeal the case to the Supreme Court. The adverse ruling still cast doubt on the centerpiece of Mr. Trump’s trade strategy, which relies on a 1970s law to impose sweeping duties on dozens of the country’s trading partners. Mr. Trump has harnessed that law — the International Emergency Economic Powers Act, or IEEPA — to raise revenue and to pressure other countries into brokering favorable deals. The law has typically been reserved for sanctions and embargoes against other nations.
The Constitution grants Congress the power to “lay and collect Taxes, Duties, Imposts and Excises” and to “regulate Commerce with foreign Nations.” U.S. Const. art. I, § 8, cl. 1, 3. Tariffs are a tax, and the Framers of the Constitution expressly contemplated the exclusive grant of taxing power to the legislative branch; when Patrick Henry expressed concern that the President “may easily become king,” 3 Debates in the Several State Conventions 58 (Jonathan Elliot ed., 1836), James Madison replied that this would not occur because “[t]he purse is in the hands of the representatives of the people,” id. at 393.
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IEEPA provides that, after declaring a national emergency pursuant to the NEA, the President may “investigate, block during the pendency of an investigation, regulate, direct and compel, nullify, void, prevent or prohibit, any . . . importation or exportation of . . . any property in which any foreign country or a national thereof has any interest.” 50 U.S.C. § 1702(a)(1)(B). Notably, IEEPA does not use the words “tariffs” or “duties,” nor any similar terms like “customs,” “taxes,” or “imposts.” IEEPA also does not have a residual clause granting the President powers beyond those which are explicitly listed.