Trump invoked a law called the International Emergency Economic Powers Act on April 2 to set a blanket 10% tariff on all imports and, initially, additional duties on almost 60 countries that have the largest trade surpluses with the US.

An initial tranche of cases challenging the Trump administration’s widespread tariffs hinge on similar arguments over illegal use of presidential powers.

Gov. Newsom says California will challenge President Trump’s authorities to impose tariffs under the International Emergency Economic Powers Act.