The Obligation not to Defeat the raison d'etre of a Treaty: The Legal Nature of Article 18 VCLT and New Developments in the Law of Treaties

《维也纳条约法公约》第18条规定，各国有义务在下列情况下不得在条约生效前破坏条约的目的和宗旨：(A)条约已签署，或(B)它已表示同意在条约生效之前接受条约的约束，但此种生效不得不当推迟。因此，虽然条约在生效前一般不具有法律效力，但第18条对已签署或批准条约的国家的行动自由有某些限制。然而，第18条的轮廓是模糊的。与这一规定有关的现有学术文献很少，国家实践支离破碎，没有一个国际法庭对这一义务进行过透彻的分析。还有人感到关切的是，与合同条约相比，该条款不太容易在立法条约方面产生明确界定的义务，因此有必要审查某一类条约是否可能要求“调整”适用第18条，以维护该条款的效力。此外，随着多边环境协定的相继出现，以及需要确保有效管理这些协定，某些表示同意受约束的“新”方法已经演变，包括缔约方会议的决定、不遵约程序和默示接受程序。这些可能属于《维也纳条约法公约》制度所规定的表示同意的方法，但关键问题是第18条是否适用并触发临时义务，以及是否可以用它来界定各国在解决环境问题方面的义务，以及在这种情况下，从什么时候开始。这个问题在整个学术研究中都没有被探讨过。条约法中研究不足的另一个问题是《维也纳条约法公约》第18条和第25条之间的联系，以及第18条的适用是否延伸到条约的临时适用。因此，本文试图对《公约》第18条的法律性质、范围和内容作出全面的回答。因此，本论文回答了以下分问题：a)该条款的产生基础是什么；b)在什么情况下可以说某些行为“破坏了”条约的目的和宗旨；c)诚实信用原则相对于第18条发挥了什么作用；d)该条款在什么时间框架内适用，第18条的适用是否延伸到条约的临时适用，以及该条款如何应对表示同意受约束的方法的新发展；和e)与合同条约相比，第18条在立法条约领域的适用性如何？为了回答这些问题，本论文汇集了两种方法：理论方法和实证法律研究的定性方法，通过使用问卷来审查各国对第18条《维也纳条约法公约》的当代理解。收集到的信息可能有助于对比或证实理论上的发现，并进一步使论文能够从当代的角度进行批判性讨论。

Article 18 of the Vienna Convention on the Law of Treaties (VCLT) imposes an obligation on States not to defeat the object and purpose of a treaty prior to its entry into force when: (a) it has signed the treaty or; (b) it has expressed its consent to be bound by the treaty, pending the entry into force of the treaty and provided that such entry into force is not unduly delayed. Thus, whereas treaties do generally not have legal effect before becoming effective, Article 18 entails certain limitations upon the freedom of action of States that have signed or ratified a treaty. However, the contours of Article 18 are blurred. Existing academic literature relating to the provision is sparse, State practice is fragmentary, and no international tribunal has ever provided a thorough analysis of the obligation. There is also concern that the provision is less prone to creating a well-defined obligation in relation to law-making treaties than contractual treaties, wherefore there is a need to examine if a certain type of treaty may call for an 'adjusted' application of Article 18 in order to preserve the effectiveness of the provision. Moreover, with the ensuing emergence of multilateral environmental agreements and the need to ensure the efficient managing of such, certain 'new' methods of expressing consent to be bound have evolved, including decisions of Conferences of the Parties, non-compliance procedures, and tacit acceptance procedures. These may fall under the methods of expressing consent regulated by the VCLT regime, but the crucial question is if, and in that case from what time, Article 18 applies and triggers the interim obligation and if it can be utilised in defining States' obligations in addressing environmental problems. This issue is unexplored in academic research in its entirety. Another issue which is under-researched in the law of treaties is the nexus between Articles 18 and 25 VCLT, and whether the application of Article 18 extends to the provisional application of treaties. This thesis accordingly seeks to provide a comprehensive answer to the question of what the legal nature, scope and content of Article 18 VCLT is. As such, the thesis answers the following sub-questions: a) what is the genetic foundation of the provision; b) when can certain conduct be said to 'defeat' the object and purpose of a treaty; c) what role does the principle of good faith play in relation to Article 18; d) within what temporal frameworks does the provision apply, does the application of Article 18 extend to the provisional application of treaties, and how does the provision cope with new developments in methods of expressing consent to be bound; and e) how does Article 18 fit within the realm of law-making treaties as compared to contractual treaties?In order to answer these questions, the thesis brings together two forms of methodologies; a doctrinal method and a qualitative approach to empirical legal research, examining what contemporary understandings States have of Article 18 VCLT through the use of a questionnaire. The information collected may serve to contrast or confirm the doctrinal findings, and further enables the thesis to engage in a critical discussion from a contemporary point of view.