Summary: Congress has not delegated (and may not delegate) all power over tariff enactment to the president. It would violate the separation of powers.

The Court of International Trade said the U.S. Constitution gives Congress exclusive authority to regulate commerce with other countries that is not overridden by the president’s emergency powers to safeguard the U.S. economy.

“The court does not pass upon the wisdom or likely effectiveness of the President’s use of tariffs as leverage,” a three-judge panel said in the decision to issue a permanent injunction on the blanket tariff orders issued by Trump since January. “That use is impermissible not because it is unwise or ineffective, but because [federal law] does not allow it.”