Senator Ron Wyden is once again drawing a line in the sand over presidential tariff powers. The Oregon Democrat, who serves as Ranking Member of the Senate Finance Committee, has introduced legislation aimed at reining in President Trump’s ability to impose sweeping tariffs without meaningful congressional oversight.

The legislative pushback

Back in October 2025, he supported a bipartisan Senate resolution aimed at repealing Trump’s global tariffs entirely.

Then came February 2026. After the Supreme Court invalidated certain Trump tariffs in a 6-3 decision, Wyden introduced the Tariff Refund Act of 2026 (S. 3905). The bill would require refunds of tariffs deemed illegal by the court, with a 180-day window for compliance.

The most recent flashpoint arrived on July 14, 2026, when Wyden teamed up with House Ways and Means Ranking Member Richard Neal to publicly condemn provisions within the Sanctioning Russia Act. Their concern was not the sanctions themselves but rather what Wyden called a “Trojan horse,” provisions that would grant the president enhanced unilateral authority to impose tariffs as high as 100% on major trading partners, including US allies.

Wyden described the proposed new tariff authority as a “Trojan horse” that could trigger higher tariffs and economic disruption.

The bigger picture: Congress vs. the executive branch

The Constitution originally vested trade authority in Congress. Over decades, lawmakers gradually delegated that power to the executive branch, mostly through mechanisms like the International Emergency Economic Powers Act (IEEPA) and various national security provisions, including Section 232 of the Trade Expansion Act of 1962 and Section 301 of the Trade Act of 1974.

The Supreme Court’s 6-3 decision striking down certain tariffs was, in itself, a remarkable judicial check on executive trade authority. The October 2025 resolution had bipartisan support, suggesting that discomfort with unchecked tariff powers extends beyond Democrats.

For Wyden specifically, the thread connecting his various legislative efforts is consistent: tariff authority should flow through Congress, not around it. Whether the vehicle is a refund bill after a Supreme Court ruling or opposition to new executive powers buried in a sanctions package, the underlying argument stays the same.

What investors should watch

The practical question is whether any of this legislation has a realistic path to passage. The dynamics shift when tariff provisions get embedded in must-pass legislation, like sanctions bills or appropriations packages. That’s precisely the scenario Wyden is flagging with his “Trojan horse” warning about the Sanctioning Russia Act.