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The Specially-Affecting States Doctrine

  • Shelly Aviv Yeini (a1)

The orthodox view of the Specially-Affected States Doctrine (SASD), grounded in the International Court of Justice's (ICJ) 1969 judgment in the North Sea Continental Shelf cases, is that practice leading to the emergence of a customary rule must include that of states “whose interests were specially affected.” The framing of this passage of the North Sea Continental Shelf judgment seems to imply both a positive and a negative importance for the practice of specially-affected states. Such practice is a requirement for the emergence of a new rule of customary international law. Acceptance by specially-affected states is, in other words, necessary but not sufficient for a rule of custom to emerge. Whether practice of specially-affected states can be sufficient to form a general custom is not resolved by this formulation, although it seems reasonable to infer that the ICJ had in mind that the combined involvement of specially-affected and other states was needed for the formation of such a rule of customary international law concerning basic principles of continental shelf delimitation. Conversely, the absence of rule-supporting practice by specially-affected states would have a negating effect on the emergence of a rule of customary international law, despite rule-affirming practice of states not specially affected. On this view, practice of only such states could not crystalize into a custom. One commentator has suggested that the negative construction does not mean that a single specially-affected state necessarily holds veto power over the formation of a new rule of customary international law, but asserted that “[i]f several ‘states whose interests are specially affected’ object to the formation of a custom, no custom can emerge.” Unsurprisingly, given this level of abstraction, such formulations do not themselves provide specificity as to how many (or which) specially-affected states would be sufficient to prevent the formation of a custom in a particular situation.

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1 North Sea Continental Shelf Cases (Ger./Den.; Ger./Neth.) 1969 ICJ Rep. 3 (Feb. 20).

2 Id. at 43.

3 Scharf, Michael P., Accelerated Formation of Customary International Law, 20 ILSA J. Int'l & Comp. L. 305, 316 (2014).

4 Dinstein, Yoram, The Interaction Between Customary International Law and Treaties, in Collected Courses of the Hague Academy of International Law, Vol. 322, at 243, 289 (2007).

5 Dinstein, Yoram, The ICRC Customary International Humanitarian Law Study, 82 Int'l L. Stud. 99, 109 (2006).

6 Id.

7 Id.

8 Heller, Kevin Jon, Specially-Affected States and the Formation of Custom, 112 AJIL 200–01 (2018). See also Baxter, R.R., Treaties and Custom, in Collected Courses of the Hague Academy of International Law, Vol. 129, at 27, 66 (1970); North Sea Continental Shelf Cases, supra note 1, at 19.

9 Customary International Humanitarian Law (Jean-Marie Henckaerts & Louise Doswald-Beck eds., 2005) (a study by the International Committee of the Red Cross) [hereinafter Study].

10 Major J. Jeremy Marsh, Lex Lata or Ferenda, Lex: Rule 45 of the ICRC Study on Customary International Humanitarian Law, 198 Mil. L. Rev. 116, 152 (2008).

11 Study, supra note 9, at xliv.

12 Id. at xliv–xlv.

13 Bellinger, John B. III & Haynes, William J. II, A U.S. Government Response to the International Committee of the Red Cross Study Customary International Humanitarian Law, 89 Int'l Rev. Red Cross 443, 446 (2007). The United States Response was intended to be an initial response until its officials can better review the Study (id. at 443–44). Thus far, no other document has been published by the U.S. government on the matter.

14 Bellinger & Haynes, supra note 13, at 445–46.

15 Id. at 445 n. 4.

16 Study, supra note 9, at 151.

17 Bellinger & Haynes, supra note 13, at 455.

18 Id. at 456; U.S. Department of Defense, Law of War Manual, at para. (2015) (updated May 2016).

19 Bellinger & Haynes, supra note 13, at 457.

20 Henckaerts, Jean-Marie, Customary International Humanitarian Law: A Response to US Comments, 89 Int'l Rev. Red Cross 473, 482 (2007).

21 Id.

22 Id.

23 Heller, supra note 8, at 219.

24 Study, supra note 9, at xlv.

25 Meron, Theodor, The Continuing Role of Custom in the Formation of International Humanitarian Law, 90 AJIL 238, 249 (1996).

26 Charles De Visscher, Theory And Reality In Public International Law 149 (1957).

27 Anonymous [Holmes], Book Notices, 14 Am. L. Rev. 233, 234 (1880).

28 Landmark Cases in Public International Law 294 (Eirik Bjorge & Cameron Miles eds., 2017) (emphasis added), citing Baxter, supra note 8, at 66.

29 Bellinger & Haynes, supra note 13, at 445.

30 Meron, supra note 25, at 249.

31 Worster, William Thomas, The Transformation of Quantity into Quality: Critical Mass in the Formation of Customary International Law, 31 Boston U. Int'l L.J. 1, 63 (2013).

32 Posner, Eric A. & Goldsmith, Jack L., A Theory of Customary International Law 77 (John M. Olin Program in Law and Economics Working Paper No. 63, 1998).

33 Dustin A. Lewis, Gabriella Blum & Naz K. Modirzadeh, War-Algorithm Accountability (2016), available at (emphasis in original).

34 Study, supra note 9, at xliv.

35 Post, Harry H.G., The Role of State Practice in the Formation of Customary International Humanitarian Law, in On the Foundations and Sources of International Law 129, 142 (Dekker, Ige F. & Post, Harry H.G. eds., 2003).

36 This is not intended to suggest that omissions may not constitute practice. To the extent states that do not possess nuclear weapons do so because of a belief that such weapons are illegal, such opinio juris would be relevant in establishing custom. As has long been recognized, the reasons beyond the omissions of states matter for purposes of developing custom.

37 Erakat, Noura, The U.S. v. The Red Cross: Customary International Humanitarian Law and Universal Jurisdiction, 41 Denver J. Int'l L. & Pol'y 225, 233 (2013); Kennedy, David, When Renewal Repeats: Thinking Against the Box, 32 N.Y.U. J. Int'l L. & Pol. 335, 355 (2000).

38 See Marsh, supra note 10, for the distinction between lex lata and lex ferenda in customary international law.

39 MacLaren, Malcolm & Schwendimann, Felix, An Exercise in the Development of International Law: The New ICRC Study on Customary International Humanitarian Law, 6 German L.J. 1217, 1232 (2005).

40 Akehurst, Michael, Custom as a Source of International Law, 47 Brit. Y.B. Int'l L. 1, 12 (1974–1975); see also Scharf, supra note 3, at 317.

41 Roberts, Anthea E., Traditional and Modern Approaches to Customary International Law: A Reconciliation, 95 AJIL 757, 767 (2001), citing the works of Charney, Chodosh, Schacter, and Weisburd. It is important to note that this work is prior to the ICRC Study of 2005. See also Scharf, supra note 3, at 317.

42 Göksel, Nilüfer Karacasulu, Globalisation and the State, IX J. Int'l Aff. 2 (2004).

I thank Professor Ariel Bendor for his guidance and many constructive and valuable comments to this piece. I also thank Dr. Ziv Bohrer for his helpful contribution.

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