A group of small business owners begin their challenge to President Donald Trump's tariffs in a small Manhattan courthouse Tuesday, arguing the president did not have the legal authority to exact such sweeping change without congressional approval.

A panel of judges on the Court of International Trade heard first arguments in a lawsuit challenging Trump's tariffs even as the White House has already negotiated down some of the original duties put in place last month.

In April, the Trump administration imposed a 20% tariff on all goods coming in from the EU, 25% from Mexico, and up to 145% on Chinese goods. The U.S. has paused some of the taxes to allow 90 days for negotiations for select nations which will expire July 8. While a 10% tariff remains in place for most countries, the U.S. recently agreed to drop their tariffs on Chinese goods to 30%.

The lawsuit was brought by a coalition of small businesses that included a New York liquor distributor, Utah pipe company, Virginia electronics store, Pennsylvania-based tackle shop, and Vermont cycling company.

The businesses are arguing their reliance on imports from countries such as China and Mexico will uniquely harm their companies and called the administration's move an "unprecedented power grab."

"If actually granted by statute, this power would be an unlawful delegation of legislative power to the executive without any intelligible principle to limit his discretion," the plaintiffs argued.

Attorneys with the Department of Justice have defended the administration's actions under an invocation of the International Economic Emergency Powers Act, enacted in 1977, saying Congress grants the president the authority to impose some tariffs under the guise of a national emergency.

"Plaintiffs' proposed injunction would be an enormous intrusion on the president's conduct of foreign affairs and efforts to protect national security under IEEPA and the Constitution," they argued.

The small business lawsuit will be heard by three judges, Gary S. Katzmann, Timothy M. Reif, and Jane A. Restani, who were appointed by Presidents Barack Obama, Donald Trump, and Ronald Reagan, respectively. There are currently six unique lawsuits against Trump's tariffs, including a case filed by a coalition of 12 state attorneys general.

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