President Trump took executive action to impose 50% tariffs on a wide range of imports from Canada.

Trump signed three proclamations formalizing the tariffs, which were made by invoking Section 338 of the Tariff Act of 1930, often referred to as the Smoot-Hawley Tariff Act. The century-old law is a different statute than the law Trump previously cited ‒ the International Emergency Economic Powers Act of 1977 ‒ in his push to use presidential emergency powers to impose reciprocal tariffs on countries.

The Supreme Court in February blocked Trump's use of emergency powers to impose tariffs under the 1977 law, forcing the White House to pursue other legal avenues to unilaterally levy fees on imports.