The data also suggest that theories that explain the use of contracts by historical conventions leave many themes unexplained. Although some scientists, for example, have argued that dependence on pathways explains why treaties are particularly common in human rights and are lacking in trade, Table 2 shows that neither subject is a particularly striking outlier. While in the field of human rights treaties are somewhat widespread (17 per cent of all agreements), the choice of this instrument remains the exception and not the norm. Similarly, the application of contracts in sectors such as trade, trade and finance is close to the 5% average, raising the question of whether the scarcity of the instrument in these areas can best be explained by historical events or whether it reflects another aversion to the treaty, which also concerns other areas. In summary, it is difficult to explain the diversity of contract prevalence in the different disciplines of conventional theories. Finally, some scientists have argued that a key difference between congressional contracts and executive agreements lies in the information produced in the process of obtaining legislative approval. Footnote 58 That is, in entering into a contract agreement, the executive must disclose important private information to be persuasive and to ensure the approval of a qualified majority in the Senate. This dynamic can be highlighted by the example of John Yoo, who considers a potential military conflict between the United States and China over territory and negotiations on the division of that territory. The domestic political struggle for treaty approval requires negotiators to communicate to the Senate the chances of a war against China. Yoo argues that observing this process would allow China to obtain more accurate information about the American faith than the congressional executive agreement provides.
China can therefore insist that the agreement be concluded in the form of a treaty and, since the underlying information is more precise, it is encouraged to strengthen confidence in continued compliance with the agreement. Now let`s look at the case of executive agreements alone. As noted above, the TIF does not distinguish between the executive agreements of Congress, although the estimated share of the first agreements is between 5 and 6% of all agreements. To take into account the fact that some international instruments are exclusive executive agreements that should be excluded from the analysis, this study uses a sensitivity analysis. Footnote 102 For much of U.S. history, U.S. courts231 and officials232 have understood common law as a binding U.S. national law in the absence of executive or legislative oversight. Around 1900, in The Habana Package, the Supreme Court declared that international law “is part of our law”” 233 Although this description may seem simple, developments in the 20th century complicate the relationship between international customary and domestic law.