What is the Court of International Trade? Learn more about the judges who blocked Trump's tariffs.

Federal judges in the U.S. have challenged the Trump administration on everything from deportations of immigrants to mass layoffs of government workers. Now, the U.S. Court of International Trade is stepping in to challenge President Trump's sweeping tariffs.

The New York-based court late Wednesday struck down most of the tariffs implemented under Mr. Trump, dealing a serious blow to one of his signature economic policies. Mr. Trump has said tariffs are necessary to erase the trade deficit, make the U.S. more competitive and energize the U.S. manufacturing sector. 

The ruling, which the Trump administration has already appealed, voids both a 10% baseline tariff on most countries introduced on April 2 in what the president referred to as "Liberation Day," and also blocks a separate set of levies imposed on China, Mexico and Canada. It does not impact U.S. tariffs assessed on specific sectors, including steel, aluminum and autos.