Since each observation in the dataset is a year of agreement, the analysis takes into account variations in the durability of different types of agreements, keeping the other characteristics constant. Differences in shelf life are estimated using a survival time analysis. These methods are also known as studies of the history of events. Footnote 88 Before proceeding, it is useful to define some key terms. Survival time analysis is mainly used in the medical sciences using the terminology most commonly found in clinical trials. A “subject” is a unit of observation, here an agreement. An “event”, a “death” or a “failure” are synonymous with the occurrence of interest similar to an incident, in the sense the exit of an agreement. The “survival time” is the period between the beginning of the observation and the occurrence of the incident, in this way the period during which an agreement is in force. Agreements in force during the last observation period are considered “legally censored”, i.e. with a survival time that has a known lower limit and an unknown upper limit, as it cannot be observed how long the agreement ultimately lasts. Footnote 89 Finally, a “hazard rate” refers to the probability that an event will occur. Despite these limitations, this study helps to inform the debate on the continued relevance of the treaty.
The conclusions are consistent with the view that the treaty grants the parties certain advantages that the agreement between Congress and the executive branch does not provide, leading to qualitatively different agreements. Despite the decline in its use, the Treaty seems to retain an important role as a political instrument. In particular, the optimal choice between international agreements may require a presidential administration to carefully assess the strength of the commitment, the private information disclosed to the public, the domestic public costs, and the ease with which an agreement can be terminated. Treaties and agreements between Congress and the executive reflect different trade-offs between these characteristics, and the task of the treaty can therefore negatively affect the ability of the executive branch to adapt an agreement to a particular context. Therefore, policy recommendations calling for the abandonment of the Treaty appear premature and may have unintended consequences. 33 Yoo, John C., Laws as Treaties?: The Constitutionality of Congressional-Executive Agreements, 99 Mich. L. Rev.
757 (2001) (argues both against the “transformationists” who introduce the idea of constitutional moments and against the “excluders” who see treaties as the only way to enact binding international agreements). Why did the powers of the executive become more private during the Convention? George Washington is to blame, as well as the determined delegates who relentlessly lobbied for a robust executive branch. .