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The three judges of the CIT found unanimously, with good reason, that the worldwide and retaliatory tariffs “lack any identifiable limits” and are “unbounded . . . by any limitation in duration or scope” and thus did not fit IEEPA’s statutory definition of an emergency tariff.

Trump supporters have argued that Congress has delegated broad authorities to the president to set tariffs under a variety of statutes. But each such delegation has different conditions and limitations; what matters is that these tariffs have been justified and defended in court as national emergencies under IEEPA. The courts have been unpersuaded that we live in a state of permanent national emergency that is global in scope and decades-long in duration, requiring swift executive action on the theory that Congress could never assemble in time to address the issue.

As the court noted, it’s not even obvious that the statutory language (of IEEPA) delegates any tariff power at all. Consider what the statute empowers the president to do:

investigate, block during the pendency of an investigation, regulate, direct and compel, nullify, void, prevent or prohibit, any acquisition, holding, with-holding, use, transfer, withdrawal, transportation, importation or exportation of, or dealing in, or exercising any right, power, or privilege with respect to, or transactions involving, any property in which any foreign country or a national thereof has any interest by any person, or with respect to any property, subject to the jurisdiction of the United States.

As the court observed:

Notably, when drafting IEEPA, Congress did not use the term “tariff” or any of its synonyms, like “duty” or “tax.” There are numerous statutes that do delegate to the President the power to impose tariffs; in each of these statutes that we have identified, Congress has used clear and precise terms to delegate tariff power, reciting the term “duties” or one of its synonyms. In contrast, none of these statutes uses the broad term “regulate” without also separately and explicitly granting the President the authority to impose tariffs. The absence of any such tariff language in IEEPA contrasts with statutes where Congress has affirmatively granted such power and included clear limits on that power.

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Three concurring judges, while joining the opinion, added their concern that Trump’s “interpretation of IEEPA would be a functionally limitless delegation of Congressional taxation authority,” which would present serious constitutional questions — a position for which they invoked the views of Justice Neil Gorsuch.