Further, the government and the Mexican nationals argued that the ATS gave federal courts jurisdiction to hear tort claims against foreign citizens, but did not allow private individuals to bring those suits.

The federal district court disagreed with the government's contention that the FTCA claim did not apply, finding that the plan to capture Alvarez-Machain was developed on U.S. soil and therefore covered.

The court found that José Francisco Sosa, one of the Mexican nationals who kidnapped Álvarez-Machaín, had violated international law and was therefore liable under the ATS.

The Court was tasked with deciding whether the Alien Tort Statute permits private individuals to bring suit against foreign citizens for crimes committed in other countries in violation of the law of nations or treaties of the United States, and whether an individual may bring suit under the Federal Tort Claims Act for an arbitrary arrest that was planned in the United States but carried out in a foreign country.

Instead, it was intended only to give courts jurisdiction over violations accepted by the civilized world and defined with specificity comparable to the features of the 18th-century paradigms (piracy, ambassadors, and safe conduct).

Instead, the ATS is a jurisdictional statute, which means that the set of justiciable torts is limited to those defined as prohibited norms under either the law of nations or treaties adopted by the United States.

The majority's discussion of treaties serves only to illuminate which sources courts can look to when determining what constitutes the law of nations, as the fact pattern of the case concerns only the latter.

Though the Court does not explicitly pinpoint the policy, it implicitly adopts a hostis humani generis theory and rejects a transitory tort basis for jurisdiction.

In Filártiga, the Second Circuit adopted the hostis humani generis rationale, deeming irrelevant the fact that the plaintiff could have a remedy under Paraguayan law (lex locus delicti).

In Chavez v. Carranza,[9] the Sixth Circuit adopted a ten-year statute of limitations for ATS claims, though allowing for equitable tolling in the interests of fairness.