CYIL vol. 9 (2018)

MARTIN FAIX – ONDŘEJ SVAČEK CYIL 9 ȍ2018Ȏ effects occur if other States and the international community can legitimately expect that a State will make its dissenting position known, nevertheless this State will finally remain silent. Mere passivity or absence of condemnation does not amount to acquiescence. Where to draw line remains unclear, but the restrictive (or more strict) approach when qualifying silence as acquiescence in cases concerning use of force can be supported by pointing out a parallel with assessment of conduct in other cases in which substantial (or highly protected values) were at stake. In the Malaysia v. Singapore case, the ICJ dealt with preconditions for passing of sovereignty over territory and in this context it argued that: “Critical for the Court’s assessment of the conduct of the Parties is the central importance in international law and relations of State sovereignty over territory and of the stability and certainty of that sovereignty. Because of that, any passing of sovereignty over territory on the basis of the conduct of the Parties, as set out above, must be manifested clearly and without any doubt by that conduct and the relevant facts.” 24 In other words, because of the high-ranking value at stake, the manifestation of the intent must be clear. The higher the value, which the norm is protecting, the higher expectations on the clarity of legal conviction to be derived from the inaction have to be applied in order for such inaction to count as acquiescence with all the possible effects, Besides States, the most relevant actors and members of international society are international organizations. Consequently, the question appears whether and if so under which conditions and how their practice is relevant. Some aspects of this issue seem indeed to be uncontroversial. With regard to conventional rules, if an international organization is a party to a treaty, its practice is relevant. Especially in cases, when member states of the organization are treaty parties in their own right, as this is for example the case with membership of the EU and the 28 EU member states in the WTO, seems this conclusion consequent and beyond any doubt, since it fully corresponds with the well-established principle that international organizations are legal entities separate from their members. With regard to customary international law, two issues are again without any doubt. First, that international organizations are subjects of general (customary) international law 25 and second, that practice and opinio iuris of States can be deduced from acts of states in connection with the activities of international organizations. How much however acts and procedures of international organizations can constitute a contribution to (in other words, how they can contribute to making of ) customary international law, remains controversial. One of the underlying problems is lack of clarity on the question whether the States’ participation in procedures and acts of the organization (such as voting or statements) may be understood also as expression of the Member States’ own legal position and thus as State practice, and not a practice of the organization as such. If for example the UN Security Council, the prohibition on the use of force: normative volatility and legislative responsibility. Journal on the Use of Force and International Law . 2017, vol. 4, issue 1, p. 14. 24 Sovereignty over Pedra Branca/Pulau Batu Puteh, Middle Rocks and South Ledge (Malaysia v. Singapore) , Judgment, I.C.J. Reports 2008, p. 51, para. 122. 25 International organizations are subjects of international law and, as such, are bound by any obligations incumbent upon them under general rules of international law, under their constitutions or under international agreements to which they are parties. Cf. Interpretation of the Agreement of 25 March 1951 between the WHO and Egypt , Advisory Opinion, I.C.J. Reports 1980, p. 90, para. 37. which current international law connects with this legal concept. 3.3 Relevance of practice of international organizations

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