The uncertainty surrounding the Trump administration's approach to tariffs has become the norm for businesses in recent months. But, as if things weren't already chaotic enough, a legal challenge to the levies in federal court has upped the ante for companies that have been desperate for stability.

"Any decision you make today may be irrelevant by next week," says Rob Kress, the CEO and founder of supply chain consultant firm Waypost Advisors.

The legal argument against President Trump's tariffs stems from his broad use of emergency powers to justify his sweeping "Liberation Day" tariffs, and his ongoing trade war with China. Although 1977's International Emergency Economic Powers Act (IEEPA) allows the President to regulate trade in response to a national emergency, a lawsuit filed with the U.S. Court of International Trade (USCIT) asserts that the IEEPA actually exists to restrain the executive branch's ability to unilaterally enact tariffs.

The three-member USCIT unanimously agreed with that assertion in a May 28 ruling, ordering a halt to Trump's 10% blanket tariffs, as well as his levies against China. Less than 24 hours later, a federal appeals court ruled that the tariffs could stay in place while the case plays out, further muddying the waters for businesses that have already struggled to keep up with the White House's on-again/off-again policy-making.

The resulting uncertainty, Kress says, is forcing many businesses into a "wait-and-see mentality," where they're holding off on making large investments in new facilities, slowing imports from China, and in some cases, pausing hiring to avoid taking on any new fixed costs, as they continue to wait for some semblance of economic consistency and continuity.

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Although the ongoing legal challenge to Trump tariffs hasn't meaningfully changed anyone's supply chain strategies per se, Kress explains, it still represents yet another unknown element that could threaten to upend any carefully laid contingency plans that might account for levies down the line. It also gives companies even more to account for as they plan out shipping schedules and inventories, and consider moving sourcing to more tariff-friendly countries.

"The risk of the [appeals court] ruling being overturned or re-implemented through another mechanism is one that manufacturers must be prepared for," says Ashley Hetrick, the sourcing and supply chain segment leader for tax and accounting advisory firm BDO USA. 

Hetrick points out that many manufacturers have already increased production on core items and increased their safety stock levels, in hopes of offsetting anticipated costs from tariffs down the line. But if those levies are eventually struck down, companies could be left with an overstock on products and materials that they didn't need to spend money on in the first place. On a larger scale, the legal uncertainty also compromises the Trump administration's ambitious goal to negotiate trade deals with upwards of 60 nations, who could simply decide to wait out the courts rather than engage in good-faith talks.

"The real challenge now is not just legal — it is strategic," says Philip Luck, the director of the economics program for the Center for Strategic and International Studies think tank. "If the United States wants to wield economic tools effectively in pursuit of national goals, it must do so with a clear, consistent, and credible framework."

What's more, Luck says, rather than ending the uncertainty surrounding Trump's tariffs, the USCIT's ruling could actually fuel it instead, especially if the White House decides to pivot to different legal mechanisms. One such pathway would be Section 232, which Trump has already used to implement 50% levies against all foreign aluminum and steel, and gives the Commerce Department the authority to use tariffs to address threats to national security. The other would be Section 301, which Trump used against China in his first term, and allows the President to enact retaliatory trade measures to combat unfair trade practices.

That leaves international trade partners left to question whether any trade commitments made by the U.S. will actually remain in place. For businesses, erratic policy-making leads to what Luck calls an "uncertainty tax," which takes the form of suppressed growth from delayed investments, waning consumer confidence, and tighter credit. Longer term, the credibility of the U.S. as a trading partner takes a significant hit, and global investors start to look elsewhere for stability.

For now, everyone's guessing as to what comes next, Kress says. Perhaps the 90-day pause on Trump's "Liberation Day" tariffs will expire without any trade deals, or the Supreme Court will side with the USCIT and strike them down entirely. Either way, what companies need regardless of the eventual outcome is certainty, and without that, it's impossible to make the difficult decisions needed to mitigate any potential impacts.

"The decisions might be tough if some of these higher tariffs stick, but at least they'd know how to address it," Kress says.