Title: Executive Authority, Judicial Checks, and the Separation of Powers: US Tariff Measures in Trade War

Author: Chen Yongmei

Abstract: The expansion of US executive authority in tariff imposition and the judiciary’s countervailing checks during the trade war not only raise legal issues concerning tariff policy but also serve as a critical stress test for the constitutional principle of separation of powers. From the perspective of US tariff legislation enacted by Congress, Section 301 of the Trade Act of 1974 authorizes the president to address “unfair trade practices”; Section 232 of the Trade Expansion Act of 1962 authorizes the president to adjust imports on national security grounds; and the International Emergency Economic Powers Act (IEEPA) of 1977 authorizes the president to regulate international economic transactions upon declaring a national emergency. US courts have traditionally shown substantial deference in reviewing tariff measures under Section 301, and virtually no presidential action under Section 232 has ever been invalidated. However, regarding the “reciprocal tariffs” imposed through invocation of the IEEPA during President Trump’s second term, the US judiciary issued adverse rulings against the administration — first at the US Court of International Trade, then on appeal at the US Court of Appeals for the Federal Circuit (Federal Circuit), and ultimately at the Supreme Court. This series of decisions illustrates the US judiciary’s critical, albeit limited, role in checking executive authority as a matter of separation of powers.

Keywords: Executive Authority, Judicial Checks, Judicial Review, Tariff Authority, International Emergency Economic Powers Act (IEEPA), Separation of Powers, Trade War