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Jose Fransisco Sosa v. Humberto Alvarez-Machain / The United States v. Humberto Alvarez-Machain

Court Supreme Court, United States
Case number No. 03-339 and 03-485
Decision title Opinion of the Court
Decision date 29 June 2004
  • Humberto Alvarez-Machain, and others
  • Francisco Sosa
  • United States of America
Categories Human rights violations, Torture
Keywords torture, abduction, arbitrary detention, assault and battery, cruel, inhuman and degrading treatment or punishment, denial of adequate medical treatment, false arrest, false imprisonment, kidnapping, negligent employment, universal jurisdiction
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In 1990, several Mexican nationals, executing an assignment from the United States Drug Enforcement Agency, abducted one of the persons suspected of involvement in the murder of a DEA official. He was eventually acquitted of all charges by an American Court and returned to Mexico. Alvarez-Machain attempted to take legal action against the Mexican nationals involved in his arrest, and against the United States. Although the Court of Appeals had confirmed both the government’s and Sosa’s liability, the Supreme Court rejected it. Regarding the government’s liability, it argued that the US could not be held responsible for actions committed abroad, even though Alvarez-Machain’s arrest had been planned in California. Regarding Sosa, the Supreme Court held that Alvarez-Machain’s arbitrary detention was not a violation of the law of nations. The latter term, according to the Supreme Court, should be defined narrowly. It considered arbitrary detention not specific enough to be within the scope of the law of nations. 

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Procedural history

In 1990, Humberto Alvarez-Machain, a Mexican citizen and resident, was forcibly kidnapped from his home and flown to Texas where he was arrested for his participation in the kidnapping and murder of a Drug Enforcement Administration (DEA) agent and the agent's pilot. Both the Court of First Instance and Court of Appeal found this forcible abduction a violation of the extradition treaty between the US and Mexico, which barred Alvarez-Machain's trial before a US court. This decision was overturned by the Supreme Court in its 1992 ruling that the abduction did not violate the extradition treaty. Alvarez-Machain's trial was allowed to commence, albeit to no avail: he was ultimately acquitted in 1993 due to lack of evidence, after which he returned to Mexico.

Alvarez-Machain brought a lawsuit against the United States for false arrest and against several Mexican nationals, including Francisco Sosa, for violating the law of nations. The federal district court ruled that the DEA had acted lawfully when they arrested Alvarez-Machain. Therefore, it held that the United States was not liable, while Sosa’s liability was established. The Court of Appeals confirmed the findings regarding Sosa, but it remanded the question of liability of the US. Since this question was found to be a matter of exceptional public importance, an en banc court hearing was initiated to deal with this question. Here the Court of Appeal affirmed its earlier conclusion concerning Sosa, and also established liability of the United States: Machain's arrest, planned by the DEA in the United States, was found unlawful.

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Legally relevant facts

After investigating the kidnapping and murder of a US Drug Enforcement Agency (DEA) special agent, the DEA concluded that physician Humberto Alvarez-Machain had participated in the murder. It was alleged that he had prolonged the agent’s life so that others could further torture and interrogate him.  An arrest warrant was issued and the United States negotiated with the Mexican government without any formal extradition request. On 2 April 1990, Alvarez-Machain was forcibly kidnapped, e.g. by Mexican nationals who were not affiliated with either the Mexican or US government and flown to Texas, where he was arrested by the DEA (pp. 1-2). Alvarez-Machain moved to dismiss the indictment, claiming that his abduction constituted outrageous governmental conduct, and that the Court lacked jurisdiction to try him because he was abducted in violation of the extradition treaty between the United States and Mexico. The Supreme Court eventually held that the arrest did not violate the extradition treaty and that Alvarez-Machain could be tried in a US court (p. 2). He was eventually acquitted. After his return to Mexico, Alvarez-Machain filed an action against several Mexican nationals who had assisted in his arrest, the United States and four DEA agents.  

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Core legal questions

The Court of Appeals had held that the US government was liable under the FTCA. Most importantly, the Court of Appeals held that the exception to applying the FTCA, which states that the FTCA cannot be applied to claims arising in a foreign country, was not of relevance in this particular case, as Alvarez-Machain’s arrest had been planned in the United States. The Supreme Court had to assess the US government’s argument that, primarily, the DEA had been authorized by law to arrest Alvarez-Machain. This argument had previously been rejected by the Court of Appeals. Secondarily, the government argued that the asserted liability falls within the aforementioned exception to application of the FTCA, as the arrest had taken place in Mexico. The Court of Appeals also established Sosa’s liability under the ATS, stating that Alvarez-Machain’s arrest and detention were arbitrary and therefore violations of the law of nations. Sosa argued, with support of the United States, that the ATS does no more than vest federal court with jurisdiction, neither creating nor authorizing the courts to recognize any particular right of action without further congressional action. 

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Specific legal rules and provisions

  • 28 United States Code, paragraph 1350.
  • 28 United States Code, paragraph 1346(b)(1).
  • 28 United States Code, paragraphs 2671-2680.

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Court's holding and analysis

The Court of Appeals had established that, although the arrest itself tookplace in Mexico, it was more relevant that the planning and direction by DEA agents took place in California (pp. 6-7). The Supreme Court rejected this reasoning, based on the “headquarters doctrine”, on two grounds: first, even if one assumes a connection of proximate cause between the planning by the DEA and Alvarez-Machain’s abduction, this does not preclude other proximate causes, such as actions by Sosa and others in Mexico (pp. 8-9). Secondly, it stated that there is good reason to think that Congress had not anticipated application of the headquarter doctrine (pp. 9 and 15-17).

The Supreme Court accepted that the ATS provided a cause of action, but only for a few international law violations: offenses against ambassadors, violation of safe conducts, and piracy (p. 25).  The Supreme Court cautioned only to expand the scope of the law of nations if norms are as specifically defined as these ‘original’ norms, as it wished to refrain from interfering with discretion of Legislative and Executive Branches (p. 33). Alvarez-Machain’s claim that arbitrary arrest falls within the scope of law of nations was thus rejected (pp. 43-44).

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Further analysis

In a commentary on the Alien Tort Statute, Bhatia discusses the legal history of this Act. Berman elaborates on the term ‘law of nations’. Ku and Yoo discuss the ability of federal courts to incorporate customary international law through the Alien Tort Statute. Venetis celebrated this case, arguing that the Supreme Court had recognized that ‘the law of nations’ can evolve over time.  Randall and Keitner argue that this case demonstrates the Court’s principle of restraint regarding application of international law. Borrowman assesses the possibilities for victims of, e.g., human rights violations in the Abu Ghraib prison to litigate in an American Court, using this case as a starting point. The Supreme Court’s ruling regarding Sosa v. Alvarez-Machain “settled a long-standing dispute about the purpose and scope of the Alien Tort Statute (...), but it raised an equally important set of questions”, as discussed by, e.g. Kontorovich; Vazquez; Bradley, Goldsmith III and Moore; and Dodge. The recent Supreme Court ruling in Kiobel v. Shell gave rise to new discussions on the ATS as well.

K. S. Bhatia, ‘Reconsidering the Purely Jurisdictional View of the Alien Tort Statute’, Emory International Law Review, 2013, vol. 27, pp. 448-508.

H. Berman, ‘The Alien Tort Claims Act and the Law of Nations’, SSRN, 12 February 2005.

J. Ku and J. Yoo, ‘Beyond Formalism in Foreign Affairs: A Functional Approach to the Alien Tort Statute’, The Supreme Court Review, 2004, pp. 153-202.

P. M. Venetis, ‘The Broad Jurisprudential Significance of Sosa v. Alvarez-Machain: An Honest Assessment of the Role of Federal Judges and Why Customary International Law can be more Effective than Constitutional Law for Redressing Serious Abuses’, Temple Political & Civil Rights Law Review, 2011, vol. 21, pp. 41-99.

K. C. Randall and C. I. Keitner, ‘Sabbatino, Sosa, and ‘Supernorms’’, in: M. H. Arsanjani, ‘Looking to the Future: Essays on International Law in Honor of W. Michael Reisman’, Martinus Nijhoff 2010.

S. J. Borrowman, ‘Sosa v. Alvarez-Machain and Abu Ghraib—Civil Remedies for Victims of Extraterritorial Torts by U.S. Military Personnel and Civilian Contractors’, Bringham Young University Law Review, 2005, vol. 2005, pp. 371-425.

E. Kontorovich, ‘Implementing Sosa v. Alvarez-Machain: What Piracy Teaches About the Limits of the Alien Tort Statute’, Notre Dame Law Review 2004, vol. 80, pp. 111-162.

C. M. Vazquez, ‘Sosa V. Alvarez-Machain and Human Rights Claims Against Corporations Under the Alien Tort Statute’, in: T. Cottier, J. Pauwelyn and E. B. Bonanomi, ‘Human Rights and International Trade’, Oxford: OUP 2005.

C. A. Bradley, J. L. Goldsmith III and D. H. Moore, ‘Sosa, Customary International Law, and the Continuing Relevance of Erie’, Harvard Law Review, 2007, vol. 120, pp. 869-936.

W. S. Dodge, ‘After Sosa: The Future of Customary International Law in the United States’, Willamette Journal of International Law and Dispute Resolution 2009, vol. 17, pp. 21-48.

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Instruments cited

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Additional materials

The International Labor Rights Forum reported on human rights lawyers’ positive reaction to this case, as the Supreme Court rejected the view that the ATS requires additional legislation before a case can be brought before a Federal Court. The New York Times assessed the ATS, after the Supreme Court’s decision to review the Court of Appeal’s judgement.

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Social media links

Jonathan Adler comments on this case on the blog of the national review.  Bloggers on Opinio Juris referred to Sosa v. Alvarez-Machain in numerous articles, especially in relation to the Supreme Court’s recent judgement regarding Kiobel v. Shell.