Procedural Posture

This document is a Petition for a Writ of Certiorari filed by the United Mexican States ("Mexico") to the Supreme Court of the United States. Mexico seeks review of a decision by the United States Court of Appeals for the District of Columbia Circuit, which affirmed the district court's denial of Mexico's petition to vacate a NAFTA Chapter 11 arbitral award rendered in favor of Lion Mexico Consolidated, L.P. The underlying arbitral tribunal had ordered Mexico to pay approximately $47 million in damages for breaching the minimum standard of treatment under NAFTA Article 1105(1).

Principal Legal Issues

The central legal issue presented is the proper standard for vacatur under Section 10(a)(4) of the Federal Arbitration Act (FAA), which authorizes courts to vacate an award when arbitrators have "exceeded their powers." Specifically, the petition asks the Supreme Court to resolve a circuit split regarding how courts should determine whether an arbitrator ignored the plain language of a contract. Mexico questions whether an award must have a "plausible" basis in the governing instrument, or whether it is sufficient that the arbitrator merely purported to interpret the agreement.

Parties' Positions

Mexico argues that the D.C. Circuit erred by applying a highly deferential, method-focused approach that asks only whether the tribunal engaged in the exercise of interpretation. According to Mexico, this approach conflicts with the text-focused standard utilized by the Second, Seventh, and Ninth Circuits, which requires an interpretive route or plausible connection to the contract's text. On the merits, Mexico contends that the NAFTA tribunal exceeded its powers by interpreting Article 1105(1)—which explicitly mandates treatment in accordance with international law for "investments of investors"—to extend substantive protections directly to "investors." Mexico asserts that this interpretation contradicts the plain and unambiguous text of the treaty.

Relief Sought

Mexico requests that the Supreme Court grant the petition for certiorari to resolve the entrenched circuit split. Mexico argues that a uniform standard is necessary to prevent forum shopping, ensure the predictability of FAA application, and protect the integrity of treaty-based arbitrations involving sovereign states.