Earlier this month, the United States Senate overwhelmingly passed the Lindsey O. Graham Sanctioning Russia and Iran Act of 2026. The bill now heads to the House for consideration. The bill’s tariff title requires the president to impose duties of up to 100 percent on all goods from three sets of countries: the five largest importers of Russian crude oil; the five largest importers of Russian natural gas; and countries facilitating Russian oil sanctions evasion. 

Our Cato colleague Scott Lincicome and Packard recently argued in The Washington Post that the bill’s tariff provisions are deeply misguided given how President Trump has abused other tariff statutes during his time in office, and Packard raised similar concerns with the bill in a Cato blog post last month. One criticism deserves more attention than it receives: the bill does not specify what data determines which countries make the list. 

In late July, the Foundation for Defense of Democracies’ advocacy arm defended the bill’s criteria as clear, reporting that, according to the bill’s sponsors, the five largest purchasers of Russian crude oil are China, India, Slovakia, Hungary, and Azerbaijan. Reuters reported the same list in mid-July, and Armed Services Committee Chairman Roger Wicker (R‑MS) recently repeated it in a press release. 

Independent research tells a different story. The Atlantic Council’s Maia Nikoladze pointed out that S&P Global and the Center for Research on Energy and Clean Air both rank Türkiye—conspicuously absent from previous reports—as the third-largest importer of Russian crude. Ukraine’s Kyiv School of Economics’ (KSE) tracking work, which follows volumes ship by ship, puts Türkiye in the same spot. A plausible explanation for the discrepancy is that the lists were constructed using the UN customs database. Türkiye’s customs data does not provide the origin of crude oil, even though Türkiye’s energy market regulator does. Customs data alone is not a clean basis for creating a list, as it relies on countries’ self-reporting.

The measurement problem runs deeper. The bill ranks importers, which means counting what arrives in each country. KSE’s latest oil tracker shows roughly a third of Russian seaborne crude departing for undisclosed destinations in June. Though the undisclosed destinations resolve in later months as ships arrive in port, some undisclosed destinations persist all the way back to January 2025, longer than any shipment takes. Pipelines make the challenge even more difficult. Gas moving through a pipeline never passes a customs house, a blind spot researchers at CEPII—a French international economics research institute—noted during the early stages of Russia’s invasion of Ukraine. 

Russia, for its part, stopped publishing customs data (along with the central bank hiding data on international reserves and the economic ministry hiding energy production figures) in March 2022, following its invasion of Ukraine. So, there is no way to fact-check the other side. Likewise, the Russia sanctions bill defines the products—crude oil as Harmonized System (HS) code 2709, natural gas as HS code 2711—and the 2711 code includes propane, butane, and other gases. 

Even with perfect data, the rankings would be a moving target. The bill looks back at the 12 months preceding enactment, then re-ranks them every 180 days for the next five years, when the bill’s tariff authorities expire. India’s imports of Russian crude fell to multi-year lows in February before setting records in July. Spain was a top-tier EU buyer in June before falling substantially in July. Which countries face up to 100 percent tariffs depends on when the clock stops and whose numbers are consulted. 

The confusion does not stop there. Under Section 113(g) of the Senate-passed legislation, the executive branch simply reports its methodology to Congress. Nothing requires disclosing the methodology well in advance or publicly vetting it, nor can Congress reject it or any determinations made pursuant to it. 

A country can escape the natural gas tariffs if its purchases amount to less than 15 percent of Russia’s total gas exports, and that country takes “significant steps” to reduce its dependence. But the denominator is Russia’s total exports. Could Moscow push an American ally over the line by simply cutting exports elsewhere? During the Senate floor debate, Sen. Blumenthal (D‑CT) assured colleagues that the legislation shields NATO members. But Türkiye is exposed on both fuels, and Hungary and Slovakia are exposed on crude, where the bill contains no exemption whatsoever. Who decides whether an ally’s steps were “significant” under the legislation? The executive branch, which offers no comfort given the administration’s record of creative (to put it mildly) tariff justifications. 

Finally, the legislation’s ratchet mostly turns one way. If a country is designated under Section 113, the statute directs that its duty rate stays above zero. A country that eliminated its purchase of Russian oil the day after its designation would face tariffs for the next 180-day review re-ranking. Section 115, the bill’s escape hatch, lets the president suspend duties so long as he notifies Congress. Congress reserved for itself a veto over presidential attempts to lift sanctions but created no similar mechanism to force tariff relief or reject a methodology it finds wanting. 

None of this is an argument against sanctioning countries helping finance Russia’s war against Ukraine. That should be debated by national security and sanctions experts. Instead, this is an argument about whether Congress should relinquish even more of its constitutionally assigned tariff powers by giving a recklessly protectionist president even more discretionary authority. The House could fix the bill by establishing a data source, publishing rankings for public contestation, further lowering tariff rates, and requiring an affirmative vote in Congress before duties could take effect. A bill whose own sponsors cannot say for certain which countries it targets is not a bill ready to become law.