The Trump administration’s global tariffs are back in court. This time the fight is over Section 301 of the Trade Act of 1974. Here is what is at stake.

Section 301 lets the US respond to foreign acts that burden American commerce. The administration opened Section 301 investigations into 60 economies, alleging they fail to prohibit or enforce bans on imports made with forced labour. In late July it imposed tariffs of 10% or 12.5%, covering more than 99% of US imports.

Countries including Canada, Mexico, India and the United Kingdom face the 10% rate because they have some forced-labour import prohibition. Most others face 12.5%, with different formulas for the EU, Taiwan, Japan, South Korea and Switzerland based on existing tariffs.

The administration has now tried a near-global tariff wall three times. In February, the Supreme Court struck down reciprocal tariffs imposed under emergency powers, forcing refunds of over $100 billion. A 10% global tariff under Section 122 could only last 150 days and expired in July. The Section 301 duties took effect on July 24.