After IEEPA: New Section 301 investigations and why public input matters

With the Supreme Court’s February 20 decision ending the use of the International Emergency Economic Powers Act (IEEPA) for across-the-board tariffs, the Trump administration has turned to another law as its main vehicle for rebuilding tariff authority. The law, Section 301 of the Trade Act of 1974, requires an administrative record and invites public comment. Public participation in the coming weeks can influence how future U.S. tariff authority is interpreted and applied.

USTR has so far opened two kinds of Section 301 investigations affecting 60 economies

Section 301 authorizes the U.S. Trade Representative (USTR) to investigate whether foreign governments are engaging in “unfair” acts, policies, or practices that burden or restrict U.S. commerce. This month, USTR launched two groups of Section 301 investigations covering 60 economies. Of those, 16 economies face investigations relating to excess manufacturing capacity. All 60 are under separate investigations involving restrictions on imports made with forced labor. If USTR makes the required findings, the president may impose tariffs or other trade restrictions. 

Historically, Section 301 has been invoked sparingly and reserved for particularly contentious trade disputes. Because it allows the U.S. to act unilaterally, it has long been controversial among trading partners. 

Still, Section 301 will likely be the principal vehicle for the current administration’s effort to rebuild tariff authority and potentially restore tariff revenue. U.S. Treasury Secretary Scott Bessent has suggested that the combination of Section 301 tariffs, temporary tariffs announced February 20 under Section 122 of the same law, and tariffs under Section 232 of the Trade Expansion Act of 1962 could return tariff revenue to the near-historically high levels reached before the Supreme Court’s IEEPA ruling. 

But unlike IEEPA, Section 301 requires a formal investigative process—including written submissions and public hearings—before tariffs can be imposed. Although it requires no additional congressional approval, Section 301 does require public notice, the development of an administrative record, and a legal determination before action is taken. This gives businesses, workers, and other stakeholders the opportunity to shape the factual and legal record on which any tariffs will rest.

Investigation 1: Are government policies creating excess manufacturing capacity?

Sixteen investigations announced March 11 focus on what the administration calls “structural excess capacity.” USTR contends that certain countries—including China, the European Union, Japan, Mexico, India, Switzerland, Norway, and others—maintain government policies such as subsidies, state financing, and industrial planning that allow factories to keep producing even when market conditions do not support it. 

The Federal Register notice initiating the investigation points to manufacturing capacity utilization below 80%—an administration-defined policy benchmark—as evidence that production is “untethered” from demand. The theory is framed at the level of national production patterns and trade balances. The unusually broad framing will matter to the findings. Scholars have been skeptical of this type of argument, even as it applies to China’s state capitalist model.

Investigation 2: Are countries adequately restricting imports made with forced labor?

USTR has also initiated 60 separate Section 301 investigations relating to forced labor, but the focus is not on whether a country relies on forced labor in domestic production. Rather, the question is whether its laws prohibit the importation of goods made with forced labor and whether those prohibitions are adequately enforced. 

USTR suggests that trading partners have failed to maintain and enforce import restrictions comparable to those in U.S. law. The U.S. already bars imports made with forced labor under Section 307 of the Tariff Act of 1930 and the China-focused Uyghur Forced Labor Prevention Act (UFLPA). UFLPA, in particular, imposes significant compliance obligations on importers and has reshaped global supply-chain due diligence practices. The investigation scrutinizes other governments’ import enforcement systems and connects that scrutiny to potential tariffs.

Written public comments due April 15

Whatever the broader policy debate, these investigations and those that may follow will proceed based on their stated rationales: structural excess capacity and enforcement of forced labor import restrictions. The administration will build its justification for future tariffs through the Section 301 process. 

Key dates are: 

Section 301 requires an evidentiary and legal record. How these practices are defined—and how closely any eventual remedy is tied to them—will shape the scope and defensibility of the policy trajectory.

What’s at stake: Tariff scope, revenue, and business planning

Replacing IEEPA tariffs with Section 301 tariffs may not mean replication. Tariffs imposed under Section 301 could be narrower or broader than prior IEEPA measures, with higher or lower rates, depending on how USTR frames and justifies the investigations. That uncertainty has implications both for federal revenue and for companies making long-term decisions about sourcing, contracts, and investment.

Tariffs function as taxes on imported goods. Changes in their level or scope affect prices, supply chains, and the allocation of costs across firms and consumers, as well as federal revenue.

In announcing the Section 301 pivot, Ambassador Jamieson Greer identified a broader list of concerns beyond excess capacity and forced labor—including pharmaceutical pricing practices, discrimination against U.S. technology companies and digital goods and services, digital services taxes, ocean pollution, and practices related to seafood and rice. Investigations into excess capacity and forced labor have now been initiated. Others could follow.

Section 301 is not an emergency power. It requires a process and record. That record—shaped by public comment—will define what counts as an “unfair” trade practice in these contexts and how far tariff authority can extend in the post-IEEPA environment.