In the case of the Mexican Union Railway, Ltd., decided in February, 1930, the British-Mexican Claims Commission, set up in accordance with the Convention of November 19,1926, added another stone to the somewhat unsteady structure of decisions on the Calvo Clause. The majority of the Commissioners enthusiastically adopted the considerationsof the United States-Mexican General Claims Commission in the North American Dredging Case, “ not thinking it necessary to repeat them, or possible to express them better.” Even the British Commissioner, Sir John Percival, who dissented, differed from the majority mainly in regard to the application of the opinion in the North American Dredging Case to the case at bar, and was not less cordial in his approval of that opinion.

Grant v. South-West Trains, Ltd. Case C-249/96. 1998 All England Law Reports (EC) 193.

Court of Justice of the European Communities, February 17, 1998.

Are employers within the European Community (EC or Community) forbidden from discriminating against their employees on the basis of sexual orientation? More generally, does the prohibition of “discrimination based on sex” contained in Article 119 of the Treaty of Rome and the Community directive requiring equal pay for men and women (Equal Pay Directive) encompass discrimination on the basis of sexual orientation? In Grant v. South-West Trains, Ltd., the European Court of Justice (ECJ) answered both questions in the negative, rejecting a strongly worded recommendation of the Court's Advocate General.

As the chairman of the panel at the 1985 ASIL Annual Meeting on the question “May the President Violate Customary International Law?” I must confess that the issue that originally troubled me when I suggested this topic for discussion remains securely hidden in the shadows of the debate. Yet I think it is of central importance. The reason it has remained obscure, despite its significance, is that it is an extraordinarily difficult intellectual puzzle. My brief purpose here is to bring it into the light, not to try to solve it.