CYIL vol. 9 (2018)

MARTIN FAIX – ONDŘEJ SVAČEK CYIL 9 ȍ2018Ȏ politically highly sensible and legally undetermined. Finally, it touches upon many core questions linked to sovereignty of States and their interests. Moreover, international law on the use of force has in the recent years been (as already mentioned) exposed to events destabilizing its existing understanding and its underlying conceptual frameworks. This contribution is also born out of dilemmas which the authors encountered when preparing a project aiming at capturing the current stage of prohibition of force under international law, with focus on practice of the Visegrad Group States. Being aware of the fact that there are nowadays different ways how to think about international law and that one’s approach necessarily influences understanding of what international law is, how it works and what it does, authors were facing simple, but fundamental methodological questions, some of which will be raised in this contribution. However, in the first step a brief remark has to be made which serves the purpose to define the scope of this contribution. First, given the complexity of the field, it is not possible for this contribution (neither for the project) to capture the whole methodological debate relevant when researching in international law on the use of force. Secondly, the questions to be addressed here arose out of authors’ primary background as international legal positivists and their choice to base the study on practice and positions of States. By addressing the issue of methodology with special focus on the area of use of force, authors hope to join the emerging voices in the community of international legal scholars 8 drawing attention to the necessity to understand the different approaches and look for dialogues between them, and secondly, to identify main doctrinal cleavages and formulate position which will be taken by authors in their ongoing research concerning use of force in international law. Since the authors decided to base their study on practice, this will constitute their focus and limitation at the same time. Practice as the decisive factor At the heart of the whole debate on current stage of international law on the use of force is evaluation of practice. As M. Wood and O. Sender note, “the practice of States plays many important roles in international law”, 9 including, but not limited to, norm- generating (creation of a norm), norm-modifying (changing the scope of application) or norm-interpreting function ( i.e. not causing change of scope of application, but just (re) interpretation). 10 It is thus the practice or, if we use another term, it is the usage, which enables to assess the scope of application and content of international norms, i.e. whether 8 Cf. ROBERTS, A.: Is International Law Really International? Oxford: OUP, 2017, 420 p.; CORTEN, O.: supra 2010, pp. 4-49; PETERS, A.: Die Zukunft der Völkerrechtswissenschaft: Wider den epistemischen Nationalismus [The Future of Public International Law Scholarship: Against Epistemic Nationalism]. Zeitschrift für ausländisches öffentliches Recht und Völkerrecht [ Heidelberg Journal of International Law ]. 2007, vol. 67, pp. 721, 748, 771. Cf. also: REISMAN, W. M.: International Law-making: A Process of Communication: The Harold D. Lasswell Memorial Lecture. Proceedings of the Annual Meeting (American Society of International Law) . 1981, vol. 75, pp. 101-120. 9 WOOD, M., SENDER, O.: State practice [online]. In: The Max Planck Encyclopedia of Public International Law . Available at: www.opil.ouplaw.com [2018-07-07]. 10 The separation of the various effects in practice may be problematic. For example, as the ILC noted with regard to the subsequent practice concerning international treaties, the lines between modification, interpretation and amendment are almost impossible to fix – cf. ILC Report, A/71/10, 2016, chap. VI, paras. 64-76, Commentary to Conclusion 7, para. 27, citing several works supporting this position. 2.

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