When Is a Treaty Self-Executing.

Several references have been made above to a distinction between treaties as self-executing and as merely executory, in which case they are enforceable only after the enactment of “legislation to carry them into effect.”360 But what is it about a treaty that makes it the law of the land and gives a private litigant the right to rely on it in a court of law? As early as 1801, the Supreme Court took notice of a treaty, and, finding it applicable to the situation before it, gave judgment for the petitioner based on it.361 In Foster v. Neilson,362 Chief Justice Marshall explained that a treaty is to be regarded “as equivalent to an act of the legislature, whenever it operates of itself, without the aid of any legislative provision.” A treaty will not be self-executing, however, “when the terms of the [treaty] stipulation import a contract— when either of the parties engages to perform a particular act. . . .” When this is the case, “the treaty addresses itself to the political, not the judicial department; and the legislature must execute the contract, before it can become a rule for the court.”363

Sometimes the nature of a treaty will determine whether it requires legislative execution or “conveys an intention that it be ‘self-executing’ and is ratified on these terms.”364 One authority states that whether a treaty is self-executing “depends upon whether the obligation is imposed on private individuals or on public authorities. . . .”

“Treaty provisions which define the rights and obligations of private individuals and lay down general principles for the guidance of military, naval or administrative officials in relation thereto are usually considered self-executing. Thus treaty provisions assuring aliens equal civil rights with citizens, defining the limits of national jurisdiction, and prescribing rules of prize, war and neutrality, have been so considered . . . .”

“On the other hand certain treaty obligations are addressed solely to public authorities, of which may be mentioned those requiring the payment of money, the cession of territory, the guarantee of territory or independence, the conclusion of subsequent treaties on described subjects, the participation in international organizations, the collection and supplying of information, and direction of postal, telegraphic or other services, the construction of buildings, bridges, lighthouses, etc.”365 It may well be that these two characteristics merge with each other at many points and the language of the Court is not always helpful in distinguishing them.366


Medellin v. Texas, 128 S. Ct. 1346, 1356 (2008), quoting Whitney v. Robertson, 124 U.S. 190, 194 (1888). [Back to text]
United States v. Schooner Peggy, 5 U.S. (1 Cr.) 103 (1801). [Back to text]
27 U.S. (2 Pet.) 253 (1829). [Back to text]
27 U.S. (2 Pet.) at 314. Generally, qualifications may have been inserted in treaties out of a belief in their constitutional necessity or because of some policy reason. In regard to the former, it has always apparently been the practice to insert in treaties affecting the revenue laws of the United States a proviso that they should not be deemed effective until the necessary laws to carry them into operation should be enacted by Congress. 1 W. Willoughby, supra, at 558. Perhaps of the same nature was a qualification that cession of certain property in the Canal Zone should be dependent upon action by Congress inserted in Article V of the 1955 Treaty with Panama. TIAS 3297, 6 U.S.T. 2273, 2278. In regard to the latter, it may be noted that Article V of the Webster-Ashburton Treaty, 8 Stat. 572, 575 (1842), providing for the transfer to Canada of land in Maine and Massachusetts was conditioned upon assent by the two states and payment to them of compensation. S. Crandall, supra, at 222–224. [Back to text]
Medellin v. Texas, 128 S. Ct. 1346, 1356 (2008), quoting Ingartua-De La Rosa v. United States, 417 F.3d 145, 150 (1st Cir. 2005) (en banc). [Back to text]
Q. Wright, supra, at 207–208. See also L. HENKIN, FOREIGN AFFAIRS AND THE CONSTITUTION 156–162 (1972). [Back to text]
Compare Foster v. Neilson, 27 U.S. (2 Pet.) 253, 314–15 (1829), with Cook v. United States, 288 U.S. 102, 118–19 (1933). [Back to text]