High Seas Jurisdiction Unbound: United States v. Trench & Sandoval (11th Cir. 2025)

Introduction

On 22 August 2025, the U.S. Court of Appeals for the Eleventh Circuit issued a per curiam decision in United States v. Martin Trench and the consolidated appeal of United States v. Benjamin Sandoval, Nos. 23-11855 & 23-11869. The appellants—two Colombian nationals—were convicted in the Southern District of Florida of conspiring to possess with intent to distribute cocaine aboard a semi-submersible vessel intercepted inside Colombia’s Exclusive Economic Zone (“EEZ”).

Their primary challenges were jurisdictional and constitutional:

Whether the Maritime Drug Law Enforcement Act (“MDLEA”), 46 U.S.C. § 70501 et seq., validly reaches conduct that occurs in a foreign state’s EEZ, which, appellants argued, is excluded from the “high seas” under international law.
Whether the MDLEA’s definition of a “vessel without nationality” exceeds Congress’s authority insofar as it attaches U.S. jurisdiction to vessels that may not be stateless under customary international law.

The Government moved for summary affirmance, asserting that existing Eleventh Circuit precedent foreclosed the challenges. The Court agreed, issuing an unpublished opinion that cements a growing line of authority holding that:

“Congress, exercising its Article I power to ‘define and punish Felonies committed on the high Seas,’ is not constrained by customary international law when defining the geographical reach of the MDLEA or what constitutes a stateless vessel.”

Summary of the Judgment

Applying the summary-affirmance standard of Groendyke Transportation, Inc. v. Davis, 406 F.2d 1158 (5th Cir. 1969), the Eleventh Circuit held that:

The defendants’ EEZ-based challenge is squarely foreclosed by United States v. Alfonso, 104 F.4th 815 (11th Cir. 2024), and United States v. Canario-Vilomar, 128 F.4th 1374 (11th Cir. 2025). Both precedents treat a foreign EEZ as part of the “high seas” for purposes of the Felonies Clause.
The MDLEA’s stateless-vessel definition survives constitutional attack because Congress is free to go beyond (or differ from) customary international law when legislating, as reconfirmed in United States v. Nunez, 1 F.4th 976 (11th Cir. 2021).
Accordingly, “the position of the Government is clearly right as a matter of law,” and the Court summarily AFFIRMED both convictions.

Analysis

Precedents Cited and Their Influence

United States v. Alfonso, 104 F.4th 815 (11th Cir. 2024) – First Eleventh Circuit case to hold directly that a foreign state’s EEZ is part of the high seas for Felonies-Clause purposes. Trench & Sandoval simply applied Alfonso’s rule.
United States v. Canario-Vilomar, 128 F.4th 1374 (11th Cir. 2025) – Restated Alfonso and added that Congress “was not constrained by international law” when defining statelessness.
United States v. Nunez, 1 F.4th 976 (11th Cir. 2021) – Clarified that a vessel claiming more than one nationality is stateless, and that customary international law contains no exclusive definition.
Older building blocks: United States v. Hernandez, United States v. Cabezas-Montano, and United States v. Estupinan, which had already upheld the MDLEA’s constitutionality without requiring a U.S. nexus.

Legal Reasoning

The Court’s logic rests on two central propositions:

Article I Supremacy Over Customary International Law. Under the prior-panel rule (United States v. White), Alfonso and Canario-Vilomar are binding until overturned en banc or by the Supreme Court. Those cases rejected the premise that international law cabins Congress’s Felonies-Clause power. Therefore, Trench and Sandoval’s arguments fail ab initio.
Functional Definition of Statelessness. Borrowing from Nunez, the Court reiterated that the MDLEA can treat a vessel as “without nationality” whenever (i) the master claims a registry not affirmed by the alleged flag state or (ii) inconsistent claims are made. Congress need not mirror international law’s tests because the Clause gives it plenary authority to “define.”

Impact on Future Litigation and the Law of the Sea

Final Nail in EEZ Challenges. Three consecutive panels (Alfonso, Canario-Vilomar, Trench & Sandoval) now categorize all EEZs as “high seas” for U.S. felony jurisdiction. Future defendants in the Eleventh Circuit face a virtually insurmountable barrier unless they secure Supreme Court or en banc review.
Recalibration of Stateless-Vessel Doctrine. By reaffirming that Congress can declare a vessel stateless on broader grounds than customary international law, the decision widens MDLEA coverage, giving Coast Guard and prosecutors clearer authority over “flag-of-convenience” or multi-registry smugglers.
Potential Circuit Split. Other circuits—most notably the D.C. Circuit in United States v. Ali (2012) (piracy context)—have signaled greater deference to international law. If another circuit rejects EEZ coverage, Supreme Court review could be triggered.
International Relations Considerations. Although purely domestic in constitutional terms, the ruling may raise diplomatic tensions. Coastal states could view unilateral U.S. enforcement in their EEZs as infringing sovereign resource rights, even if drug interdiction is widely welcomed.

Complex Concepts Simplified

Exclusive Economic Zone (EEZ): A belt of sea up to 200 nautical miles from a coastal state’s baseline where the state enjoys sovereign resource rights (fishing, oil, etc.) but not full sovereignty. International law (UNCLOS) deems it part of the high seas for criminal jurisdiction unless the coastal state legislates otherwise.
High Seas: All parts of the ocean not included in any nation’s territorial sea (usually 12 nautical miles). Under the U.S. Constitution’s Felonies Clause, Congress can criminalize conduct here regardless of a U.S. nexus.
Vessel Without Nationality (Stateless Vessel): A ship not entitled to sail under any nation’s flag. The MDLEA expands this by treating vessels with contradictory or unverified registry claims as stateless—thereby opening them to universal jurisdiction.
Summary Affirmance (Groendyke): An appellate shortcut allowing the court to affirm without full briefing or oral argument when “the position of one party is clearly right as a matter of law.”

Conclusion

United States v. Trench & Sandoval may be unpublished, but it is doctrinally potent. By embracing and extending Alfonso and Canario-Vilomar, the Eleventh Circuit has:

Declared with finality (for now) that Congress’s Felonies-Clause power extends into every EEZ worldwide, effectively erasing the EEZ/high-seas distinction for MDLEA prosecutions.
Endorsed a flexible, domestic definition of statelessness, freeing U.S. enforcement from strict adherence to customary international norms.

For practitioners, the case signals near-total jurisdictional coverage for maritime drug prosecutions in the Eleventh Circuit. Only a Supreme Court ruling or en banc reversal can unsettle this expanding authority. Until then, traffickers apprehended anywhere beyond 12 nautical miles—regardless of the claimed flag or coastal zone—remain firmly within the MDLEA’s reach.