Trump sued over 50% tariffs on Canada in latest trade challenge

A new lawsuit filed Tuesday challenges President Donald Trump's invocation of a Depression-era law to impose 50% tariffs on a range of Canadian goods.

Trump in July used Section 338 of the Tariff Act of 1930 to slap those steep tariffs on Canadian hockey sticks, wine, honey, wigs, and other products in response to alleged trade discrimination by Ottawa. It was the first time the 96-year-old law had ever been used to impose a tariff.

"Section 338 is a relic of the retaliation-based tariff policy" that has been "impliedly repealed" by subsequent legislation, the civil complaint filed in the U.S. Court of International Trade says.

The suit was filed by Gellert Global Group, a New Jersey-based food importer that says its cheeses are covered by the tariffs. The complaint asks the court to declare the tariffs unlawful, block their enforcement, and order the Trump administration to issue refunds for duties already paid, with interest.

Gellert Global is represented by the Liberty Justice Center, the same legal group that dealt a major blow to Trump's trade agenda by successfully contesting his "reciprocal" tariffs.

The Supreme Court struck those tariffs down in February. The administration is in the process of refunding the estimated $166 billion that the federal government collected from importers through the reciprocal duties.

The Liberty Justice Center is currently engaged in two other lawsuits against what it says is Trump's misuse of laws to impose sweeping tariffs.

"This case is not about the president. It is about the presidency," the group's CEO Sara Albrecht said in a statement Tuesday morning announcing Gellert Global's suit. "No president should have the power to pull a dormant statute off the shelf and use it to impose sweeping tariffs or import bans without the limits Congress required."

The White House did not immediately respond to CNBC's request for comment on the suit.