Comparative analysis based on the recent ruling of the United States Supreme Court and its parallel with Argentine doctrine on tax legality.
Author: Dr. Andrea Zavatto
Date: February 22, 2026
Original publication: Mercojuris
Área: International Trade · Customs Law · Taxation
The ruling of the United States Supreme Court and the limits on emergency tariffs
On February 20, 2026, the United States Supreme Court ruled in Learning Resources, Inc. v. Trump que la International Emergency Economic Powers Act (IEEPA) does not authorize the President to impose tariffs. Twelve years earlier, the Argentine Supreme Court, in Camaronera Patagónica S.A., had reaffirmed that export duties are taxes whose creation corresponds to Congress.
Although originating in different contexts, both precedents converge on the same institutional warning: when the Executive Branch attempts to base tax authority on broad or generic enabling provisions, the courts raise the same essential question: Where is the Act of Congress that precisely authorizes the tax?
Tariffs, economic emergency, and the principle of statutory reservation in the United States
The U.S. case arises in a context of massive tariffs imposed under an emergency declaration and defended solely on the basis of the IEEPA. The Court held that the power of “lay and collect Taxes, Duties, Imposts and Excises” pertenece al Congreso y que el verbo “regulate” cannot be interpreted as synonymous with. “tax”.
Likewise, it required clear legislative authorization for what it characterized as a “major decision” of economic policy. Beyond internal methodological differences, the institutional message was clear: economic emergency, by itself, does not transform a regulatory power into a taxing power.
Camaronera Patagónica” and the principle of tax legality in Argentina
The Argentine controversy, although earlier and of a different nature, reveals a similar tension. In Camaronera Patagónica S.A., the Supreme Court held that export duties set by ministerial resolution had an unequivocal tax nature and violated the principle of legality.
Even acknowledging the variability of the comercio exteriorthe Court insisted that Congress must clearly define the essential elements of the tax, and may—at most—authorize the Executive Branch to adjust rates within parameters previously established by law.
Constitutional convergences and limits on the taxing power
A comparative reading reveals a significant conceptual convergence. In both systems, taxes are neither presumed nor inferred from broad clauses. In the United States, the Court is skeptical that Congress has “hidden” tariff authority within an emergency statute.
In Argentina, even in the context of the dynamics of foreign trade, a complete legislative framework is required: taxable event, affected taxpayers, and applicable rate (or scale). Doctrinal differences do not alter the common core: the taxing power remains a stress test for the separation of powers..
Practical implications for international trade
This parallel is not coincidental. The Argentine Constitution of 1853 was designed under the influence of the United States model. The 1994 constitutional reform strengthened formal safeguards by prohibiting legislative delegation except in limited circumstances and by restricting necessity and urgency decrees in tax matters.
In the United States, the ruling recalibrates the IEEPA as a tool for sanctions and economic control, but not as a mechanism to redesign general tariff policy without legislative intervention. In Argentina, Camaronera Patagónica it remains fully valid as a warning of legislative technique: invoking an emergency does not replace the principle of statutory reservation when taxes are at stake.
In short, both precedents remind us that economic policy may require flexibility, but the power to tax demands explicit democratic legitimacy. When taxation “returns” to Congress, it is not a matter of formalism, but of the basic constitutional logic of representative systems.
Dr. Andrea Zavatto
Attorney – Specialist in Customs Law, Foreign Exchange Law, and Legal Metrology
Director – MJE Comercio Exterior SRL
Consulting Partner – MJE Global (USA)
General Directorate – Dumping Experts
Article originally published in Mercojuris. Reproduced with the author’s authorization.