Throughout the Constitutional Convention, the Framers consistently expressed the desire that a national judiciary have jurisdiction over legal issues arising from the nation’s international rights and obligations. Nevertheless, while such a proposition was part of both the Virginia and New Jersey Plans, the delegates were unable to reach a consensus, putting forward numerous alternative formulations. They wanted, in Edmund Randolph’s words, to protect “the security of foreigners” and “the harmony of states and the citizens thereof.”

It was not until August 27, 1787, when the delegates were refining the Committee of Detail’s jurisdictional language, that John Rutledge of South Carolina moved to include the words “and treaties made or which shall be made under their authority” after the “United States” in the first clause of what would become Article III, Section 2. That language guaranteed the federal judiciary jurisdiction over all treaties entered into by the United States from the moment of its independence. The proposal was unanimously approved. During ratification, Alexander Hamilton explained the provision in The Federalist No. 80, reasoning that because “the peace of the whole ought not to be left at the disposal of a part . . . the federal judiciary ought to have cognizance of all causes in which the citizens of other countries are concerned,” which “have an evident connection with the preservation of the national peace.”

The Judiciary Act of 1789 granted limited jurisdiction, and limited rights of appeal, to the newly created federal court system. Under Section 25, the Supreme Court was allowed to hear appeals from the states’ highest courts when such decisions touched on the “validity of a . . . treaty . . . or against any title, right, privilege, or exemption set up or claimed under any . . . treaty.” Outside of the appeals permitted by the Judiciary Act, the Court would not go. It refused to offer advisory opinions on the construction of treaties, as President George Washington had asked it to do in 1793, or to review veterans’ pension claims at congressional request. In the latter instance, the Court claimed that such review would exceed the judicial function and was contrary to the separation of powers.

Chief Justice John Marshall provided the earliest construction of the Article III Treaties Clause in Owings v. Norwood’s Lessee (1809), a case concerning the property claims of British subjects whose lands had been confiscated during the Revolution. The Treaty of Paris of 1783 had explicitly preserved the “just rights” of such persons to reclaim lands in certain instances. Marshall, explaining the origin of the Treaties Clause, and enforcing the application of the Treaty’s provisions, explained:

The reason for inserting that clause in the constitution was, that all persons who have real claims under a treaty should have their causes decided by the national tribunals. It was to avoid the apprehension as well as the danger of state prejudices. . . . Each treaty stipulates something respecting the citizens of the two nations, and gives them rights. Whenever a right grows out of, or is protected by, a treaty, it is sanctioned against all the laws and judicial decisions of the States; and whoever may have this right, it is to be protected. But if the person’s title is not affected by the treaty, if he claims nothing under a treaty, his title cannot be protected by the treaty.

The mere existence of a treaty, and its application to any one party in a dispute, however, does not assure federal jurisdiction. Mayor, Alderman and Inhabitants of the City of New Orleans v. De Armas (1835). While jurisdiction may extend “without regard to the character of the parties” involved in any dispute, Cohens v. Virginia (1821), the legal rights asserted by the parties must in fact flow from an enforceable treaty.

Federal jurisdiction also requires that the legal right claimed under any treaty actually be contested. For example, in Martin v. Hunter’s Lessee (1816), Justice Joseph Story noted that a claimant must have relied on a treaty provision to his detriment, with such error evident from the record. At the same time, Story declared that the record need not refer to the disputed interpretation of a treaty in specific terms, for treaties are part of “the supreme law of the land of which all courts must take notice.”

As far as the relationship between treaties and the “laws of Congress” is concerned, the Court has made a clear distinction between those cases involving claims that “grow directly out of [a] treaty” and are “thus clearly dependent upon it,” and those cases where Congress has acted upon a treaty and created legislation to effect its obligations thereunder. In the latter case, the claim must be founded on the act of Congress. United States v. Weld (1888).

Historically, the construction of treaties, especially when they are applied as domestic law, has been understood as the “peculiar province of the judiciary,” except in “cases purely political.” Jones v. Meehan (1899). But under the political-question doctrine, the courts will not determine whether a treaty obligation with another nation has been broken. Clark v. Allen (1947). And while treaties can have the force of domestic law, the Constitution remains the supreme law of the land; neither a statute nor a treaty can override the Constitution where specific constitutional guarantees are in issue. Reid v. Covert (1957).

Over the years, the Court has crafted a number of prudential rules in its interpretation of treaties. Assuming that a treaty’s text is self-executing (i.e., enforceable as domestic law without need for implementing legislation), all interpretations begin with the explicit meaning of its text. Medellin v. Texas (2008). Unambiguous textual provisions are controlling unless their plain meaning would be clearly “inconsistent with the intent or expectations” of the treaty’s signatories. Maximov v. United States (1963). The question of signatory “intent” is especially controversial. The courts will rely on clarifications, interpretations, and understandings of a treaty formulated by the executive branch. But the courts will not infer an obligation from a treaty that has not been articulated in clear terms. Society for the Propagation of the Gospel in Foreign Parts v. New Haven (1823).

Where ambiguities do exist, courts can turn to any number of other sources: (1) ratification history, Air France v. Saks (1985); (2) the understanding entertained by the political branches, Charlton v. Kelly (1913); (3) the interpretations held by administrative agencies typically charged with a treaty’s enforcement, Kolovrat v. Oregon (1961); or (4) the opinions of “sister signatories,” or those nations with which the United States has entered into the treaty, Abbott v. Abbott (2010).

Traditionally, the courts were less likely to accord the legislative branches a say in the interpretation of a treaty. Jones v. Meehan. The text would govern, Maximov v. United States, unless an ambiguity caused recourse to ratification history for clarification. See Air France v. Saks. In Sumitomo Shoji America, Inc. v. Avagliano (1982), the Court went so far as to suggest that the parties’ intent would control even over the text. Justice Antonin Scalia vigorously objected to this proposition in United States v. Stuart (1989), where the majority had limited its investigation of treaty intent to Senate floor debates. Scalia condemned the “unprecedented” use of such materials: “The question before us in a treaty case is what the two or more sovereigns agreed to, rather than what a single one of them, or the legislature of a single one of them, thought it agreed to.”

As a rule, courts will only recognize the legal validity of a treaty, and legal claims arising there-from, if it has been “executed” into federal law. This can be accomplished in two ways. In the first instance, a treaty may convey an intention that it be “self-executing,” and acknowledged as such during congressional ratification. Foster v. Neilson (1829). In the second, the treaty may require “legislation to carry [it] into effect.” Whitney v. Robertson (1888). The courts will not enforce “non–self-executing treaties” until they are carried into law by an act of Congress. (See Article VI, Clause 2). Whether a given treaty is self-executing or requires special implementing legislation to give force and effect to its provisions is generally understood as a question for the courts. Diggs v. Richardson (1976).

Federal statutes and properly executed treaties have equal status in law, the later in time taking precedence. Therefore, if Congress passes a statute that contradicts earlier treaty obligations of the United States, the courts will enforce the statute over the treaty. In order to avoid such a conflict, however, the courts will construe a law not to be in conflict with extant treaty obligations if such a construction is at all reasonable.

The jurisdictional statute regulating treaty review is currently 28 U.S.C. § 1257. It allows appeal by writ of certiorari to the Supreme Court if the validity of a treaty or of a state statute under a treaty is questioned or if “any title, right, privilege, or immunity is specially set up or claimed” under a treaty. Furthermore, under 28 U.S.C. § 1331, “district courts shall have original jurisdiction of all civil actions arising under . . . treaties of the United States.” District courts may also take jurisdiction over cases brought in state court involving treaties under the complicated rules of pendent jurisdiction.