1 See in particular Protocol Additional (I) to the Geneva Conventions of 12 August 1949, and relating to the Protection of Victims of International Armed Conflicts, 1125 UNTS 3, 8 June 1977 (entered into force 7 December 1978) (AP I), Arts 35, 55. See also Convention on the Prohibition of Military or Any Other Hostile Use of Environmental Modification Techniques, 1108 UNTS 151, 10 December 1976 (entered into force 5 October 1978).

2 Plant, Glen, Environmental Protection and the Law of War: A “Fifth Geneva” Convention on the Protection of the Environment in Armed Conflict?, Belhaven Press, London and New York, 1992Google Scholar.

3 General Assembly Sixth Committee: Summary Record of the 20th Meeting, UN Doc A/C.6/46/SR.20, 30 October 1991, para. 3.

4 Protection of the Environment in Times of Armed Conflict: Report of the Secretary-General, UN Doc. A/47/328, 31 July 1992, paras 52, 56; see also paras 48, 63.

5 International Committee of the Red Cross (ICRC), Guidelines on the Protection of the Natural Environment in Armed Conflict: Rules and Recommendations Relating to the Protection of the Natural Environment under International Humanitarian Law, with Commentary, Geneva, 2020, para. 35.

6 See e.g. comments and observations made by States and institutions quoted in Marja Lehto, Third Report on the Protection of the Environment in Relation to Armed Conflicts, UN Doc. A/CN.4/750, 16 March 2022, para. 139. Only one brief and unsatisfactory paragraph has been added to that end in the final version of the commentaries on the Draft Principles adopted in 2022: see ILC, Draft Principles on Protection of the Environment in Relation to Armed Conflicts, with Commentaries, UN Doc. A/77/10, 2022 (ILC Commentaries), p. 136, para. 4.

7 Sjöstedt, Britta, The Role of Multilateral Environmental Agreements: A Reconciliatory Approach to Environmental Protection in Armed Conflict, Hart, Oxford, 2020CrossRefGoogle Scholar; Dienelt, Anne, Armed Conflicts and the Environment: Complementing the Laws of Armed Conflict with Human Rights Law and International Environmental Law, Springer, Cham, 2022CrossRefGoogle Scholar. See also the recent symposium co-edited by de Hemptinne, Jerôme and this author on “The Protection of the Environment during Warfare: An International Environmental Law Perspective”, Journal of International Criminal Justice, Vol. 20, No. 5, 2022Google Scholar.

8 A. Dienelt, above note 7.

9 See also, in addition to these two processes, a normative process envisaged by certain scholars which involves using IEL to inspire new IHL rules. For an illustrative case, see e.g. Hulme, Karen, “Armed Conflict and Biodiversity”, in Bowman, Michael, Davies, Peter and Goodwin, Edward (eds), Research Handbook on Biodiversity and Law, Edward Elgar, Cheltenham, 2016, pp. 263–264Google Scholar.

10 The issue had nonetheless been briefly addressed in 1985 by the Institute of International Law during its work on the effects of armed conflict on treaties: see Institute of International Law, Yearbook, Vol. 61, Part II, Session of Helsinki, Pedone, Paris, 1985, p. 223.

11 See Conference of Experts on the Use of the Environment as a Tool of Conventional Warfare (Conference of Experts), “Chairman's Conclusions”, July 1991, para. 11, available at: https://gac.canadiana.ca/view/ooe.b4224383F/1 (all internet references were accessed in August 2023). For scholars, see e.g. Bothe, Michael, “The Protection of the Environment in Times of Armed Conflict: Legal Rules, Uncertainty, Deficiencies and Possible Developments”, German Yearbook of International Law, Vol. 34, 1991, p. 59Google Scholar.

12 See e.g. Jean d'Aspremont, “Towards an International Law of Brigandage: Interpretative Engineering for the Regulation of Natural Resources Exploitation”, Asian Journal of International Law, Vol. 3, No. 1, 2013, p. 17; Daniëlla Dam-de Jong, International Law and Governance of Natural Resources in Conflict Situations, Cambridge University Press, Cambridge, 2013, pp. 115–116; Eliana Cusato, The Ecology of War and Peace: Marginalising Slow and Structural Violence in International Law, Cambridge University Press, Cambridge, 2021, p. 91.

13 See e.g. AP I, Art. 58.

14 See e.g. Protocol on Prohibitions or Restrictions on the Use of Mines, Booby-Traps and Other Devices, as Amended on 3 May 1996, Annexed to the Convention on Prohibitions or Restrictions on the Use of Certain Conventional Weapons which May Be Deemed to be Excessively Injurious or to Have Indiscriminate Effects, 2048 UNTS 93, 3 May 1996 (entered into force 3 December 1998), Art. 9.

15 See e.g. Convention on Biological Diversity, 1760 UNTS 79, 5 June 1992 (entered into force 29 December 1993) (Biodiversity Convention), Art. 7.

16 For IEL treaties on the matter, see e.g. those mentioned in Marie G. Jacobsson, Third Report on the Protection of the Environment in Relation to Armed Conflicts, UN Doc. A/CN.4/700, 3 June 2016, paras 130–140.

17 Silja Vöneky, “A New Shield for the Environment: Peacetime Treaties as Legal restraints of Wartime Damage”, Review of European, Comparative and International Environmental Law, Vol. 9, No. 1, 2000; Michael N. Schmitt, “Green War: An Assessment of the Environmental Law of International Armed Conflict”, Yale Journal of International Law, Vol. 22, No. 1, 1997, pp. 36–41; M. Bothe, above note 11, p. 54; Richard G. Tarasofsky, “Legal Protection of the Environment during International Armed Conflict”, Netherlands Yearbook of International Law, Vol. 24, 1993, pp. 22 ff.; John P. Quinn, Richard T. Evans and Michael J. Boock, “United States Navy Development of Operational-Environmental Doctrine”, in Jay E. Austin and Carl E. Bruch (eds), The Environmental Consequences of War: Legal, Economic, and Scientific Perspectives, Cambridge University Press, Cambridge, 2010, pp. 164–165.

18 See e.g. Karine Bannelier-Christakis, “L'utopie de la ‘guerre verte’: Insuffisances et lacunes du régime de protection de l'environnement en temps de guerre”, in Vincent Chétail (ed.), Permanence et mutations du droit des conflits armés, Bruylant, Brussels, 2013, p. 405 fn. 66 ; Michael Bothe, Carl Bruch, Jordan Diamond and David Jensen, “International law protecting the Environment during Armed Conflict: Gaps and Opportunities”, International Review of the Red Cross, Vol. 92, No. 879, 2010, p. 581 ; Dapo Akande, “Nuclear Weapons, Unclear Law? Deciphering the Nuclear Weapons Advisory Opinion of the International Court”, British Yearbook of International Law, Vol. 68, 1997, p. 185.

19 See e.g. UNEP, Protecting the Environment during Armed Conflict: An Inventory and Analysis of International Law, 2009, pp. 35–40; M. G. Jacobsson, above note 16, paras 104–120; Alice Louise Bunker, “Protection of the Environment during Armed Conflict: On Gulf, Two Wars”, Review of European Community and International Environmental Law, Vol. 13, No. 2, 2004, pp. 202–203; E. Cusato, above note 12, p. 89.

20 See e.g. the theories developed in S. Vöneky, above note 17, pp. 20–32; M. N. Schmitt, above note 17, pp. 36–41; Stephanie N. Simonds, “Conventional Warfare and Environmental Protection: A Proposal for International Legal Reform”, Stanford Journal of International Law, Vol. 29, 1992, pp. 168 ff.

21 UNGA Res. 66/99, 9 December 2011, Annex.

22 See e.g. Marja Lehto, First Report on the Protection of the Environment in Relation to Armed Conflicts, UN Doc. A/CN.4/720, 30 April 2018, para. 78; D. Dam-de Jong, above note 12, p. 172; B. Sjöstedt, above note 7, pp. 150–159; A. Dienelt, above note 7, pp. 230–232.

23 See e.g. Adrian Loets, “An Old Debate Revisited: Applicability of Environmental Treaties in Times of International Armed Conflict Pursuant to the International Law Commission's ‘Draft Articles on the Effects of Armed Conflicts on Treaties’”, Review of European, Comparative and International Environmental Law, Vol. 21, No. 2, 2012, p. 133.

24 See e.g. Cyprien Dagnicourt, La protection de l'environnement en période de conflit armé, L'Harmattan, Paris, 2020, pp. 137–138.

25 See e.g. ILC Commentaries, above note 6, p. 136, para. 4; see also p. 141, para. 4, and p. 159, para. 3.

26 For explicit endorsements of the continued applicability of IEL in armed conflict, see e.g. statements from Thailand (UN Doc. A/C.6/71/SR.29, 2 December 2016, para. 10) and Portugal (UN Doc. A/C.6/73/SR.28, 10 December 2018, para. 88). For implicit endorsements, see statements made by States asking the ILC to examine (or approving the ILC's proposals regarding) the interactions between IHL and IEL in armed conflict (see e.g. Azerbaijan (UN Doc. A/C.6/73/SR.29, 10 December 2018, para. 114); Vietnam (UN Doc. A/C.6/73/SR.30, 6 December 2018, para. 44); Algeria (ibid., para. 82); Italy (UN Doc. A/C.6/70/SR.22, 23 November 2015, para. 117); Greece (UN Doc. A/C.6/70/SR.24, 4 December 2015, paras 2–3; UN Doc. A/C.6/71/SR.29, 2 December 2016, para. 17); Belarus (UN Doc. A/C.6/70/SR.24, 4 December 2015, para. 15); Slovenia (UN Doc. A/C.6/70/SR.24, 4 December 2015, para. 39); Lebanon (ibid., para. 59); Austria (ibid., para. 66); Romania (UN Doc. A/C.6/72/SR.26, 5 December 2017, para. 28); the Netherlands (ibid., para. 37); Thailand (ibid., para. 60); Malaysia (ibid., para. 120); South Africa (UN Doc. A/C.6/73/SR.30, 6 December 2018, paras 2–3)), or underlining that IHL remains the lex specialis in relation to IEL in such conflicts (see e.g. Belarus (UN Doc. A/C.6/70/SR.24, 4 December 2015, para. 15); Greece (UN Doc. A/C.6/71/SR.29, 2 December 2016, para. 17); the United States (UN Doc. A/C.6/73/SR.29, 10 December 2018, para. 41); South Africa (UN Doc. A/C.6/73/SR.30, 6 December 2018, para. 3)).

27 See e.g. above note 17.

28 See e.g. Jorge Viñualez, “Régime spécial – cartographies imaginaires: Observations sur la portée juridique du concept de ‘régime spécial’ en droit international”, Journal de Droit International, No. 140, 2013, pp. 405 ff.

29 For that test, see e.g. Jost Delbrück, “War, Effect on Treaties”, in Encyclopaedia of Public International Law, Vol. 4, 2000, p. 1371.

30 See e.g. Convention on the Law of the Non-Navigational Uses of International Watercourses, UN Doc. A/51/869, 21 May 1997 (entered into force 17 August 2014), Art. 30, which authorizes the States Parties to resort to indirect procedures in order to fulfil their obligation of cooperation “[i]n cases where there are serious obstacles to direct contacts between watercourse States”. See also ILC, Principles on Protection of the Environment in Relation to Armed Conflicts, UNGA Res. 77/104, 7 December 2022 (PERAC Principles), Principle 23(2).

31 These are not available to the aggressor State: see, respectively, ILC, Responsibility of States for Internationally Wrongful Acts, UNGA Res. 56/83, 12 December 2001, Art 23(2)(a); Vienna Convention on the Law of Treaties, 1155 UNTS 331, 23 May 1969 (entered into force 27 January 1980) (VCLT), Art. 62(2)(b). See also ILC, Report of the International Law Commission: Sixty-Third Session, UN Doc. A/66/10, 2011, p. 195, Art. 15. For detailed and rare discussion on those traditional mechanisms in relation to the applicability of IEL in armed conflict, see D. Dam-de Jong, above note 12, pp. 179–191; C. Dagnicourt, above note 24, pp. 140–143.

32 According to Article 44(3) of the VCLT, above note 31, only the provisions affected by the change of circumstances, rather than the whole treaty, might be suspended or terminated under certain conditions.

33 See e.g. J. P. Quinn, R. T. Evans and M. J. Boock, above note 17, p. 164; D. Dam-de Jong, above note 12, p. 175.

34 See ICRC, Guidelines for Military Manuals and Instructions on the Protection of the Environment in Times of Armed Conflict, UN Doc. A/49/323, 19 August 1994, Annex, para. 5; ICRC, above note 5, para. 33. The ICRC's 2020 Guidelines (above note 5) nonetheless also refer to a test of incompatibility “with the characteristics of the armed conflict”.

35 M. Lehto, above note 22, para. 79; Marja Lehto, Second Report on the Protection of the Environment in Relation to Armed Conflicts, UN Doc. A/CN.4/728, 27 March 2019, para. 28.

36 See e.g. European Court of Human Rights (ECtHR), Hassan v. United Kingdom, Appl. No. 29750/09, Judgment (Grand Chamber), 16 September 2014, paras 96–111; Inter-American Commission on Human Rights, Coard et al. v. United States, Case No. 10.951, 29 September 1999, paras 41–61; Report on Terrorism and Human Rights, OEA/Ser.L/V/II.116, Doc. 5 rev. 1 corr., 22 October 2002, paras 141 ff.; Inter-American Court of Human Rights, The Ituango Massacres v. Colombia, Preliminary Objections, Merits, Reparations and Costs, Judgment, Series C, No. 148, 1 July 2006, para. 179.

37 See e.g. Kirsten Stefanik, “The Environment and Armed Conflict: Employing General Principles to Protect the Environment”, in Carsten Stahn, Jennifer S. Easterday and Jens Iverson (eds), Environmental Protection and Transitions from Conflict to Peace, Oxford University Press, Oxford, 2017, p. 93.

38 ILC Commentaries, above note 6, p. 136, para. 4 fn. 593.

39 ICJ, Legality of the Threat or Use of Nuclear Weapons, Advisory Opinion, ICJ Reports 1996 (Nuclear Weapons Advisory Opinion), para. 32.

40 For a similar view, see D. Dam-de Jong, above note 12, p. 174.

41 Nuclear Weapons Advisory Opinion, above note 39, para. 30.

42 D. Akande, above note 18, p. 184.

43 See e.g. Karine Mollard-Bannelier, La protection de l'environnement en temps de conflit armé, Pédone, Paris, 2001, p. 267.

44 See, nonetheless, D. Dam-de Jong, above note 12, p. 125.

45 Raphaël van Steenberghe, “The Interplay between International Humanitarian Law and International Environmental Law: Towards a Comprehensive Framework for a Better Protection of the Environment in Armed Conflict”, Journal of International Criminal Justice, Vol. 20, No. 5, 2022, pp. 1144–1146.

46 On this doctrine, see e.g. Jann K. Kleffner, “The Applicability of International Humanitarian Law to Organized Armed Groups”, International Review of the Red Cross, Vol. 93, No. 882, 2011, pp. 445–449.

47 See e.g. Office of the UN High Commissioner for Human Rights, International Legal Protection of Human Rights in Armed Conflict, 2011, pp. 23–27; Tilman Rodenhäuser, Organizing Rebellion Non-State Armed Groups under International Humanitarian Law, Human Rights Law, and International Criminal Law, Oxford University Press, Oxford and New York, 2018, pp. 170–176. However, this claim remains controversial: see e.g. Jelena Pejic, “Conflict Classification and the Law Applicable to Detention and the Use of Force”, in Elizabeth Wilmshurst (ed.), International Law and the Classification of Conflicts, Oxford University Press, Oxford, 2012, p. 84; Liesbeth Zegveld, Accountability of Armed Opposition Groups in International Law, Cambridge University Press, Cambridge, 2002, p. 54

48 R. van Steenberghe, above note 45, pp. 1142–1144.

49 For such complementary role played by IEL with respect to certain aspects of the (protection of the) environment, see e.g. Karen Hulme, “Using International Law to Enhance Biodiversity and Nature Conservation during Armed Conflict”, Journal of International Criminal Justice, Vol. 20, No. 5, 2022, pp. 1171–1176; Mara Tignino and Tadesse Kebebew, “The Legal Protection of Freshwater Resources and Related Installations during Warfare”, Journal of International Criminal Justice, Vol. 20, No. 5, 2022, pp. 1221–1225; Jérôme de Hemptinne, “The Regulation of Hazardous Substances and Activities during Warfare”, Journal of International Criminal Justice, Vol. 20, No. 5, 2022, pp. 1268–1270, 1283–1285.

50 See e.g. ILC Commentaries, above note 6, p. 136, para. 4; Daniëlla Dam-de Jong, “From Engines for Conflict into Engines for Sustainable Development”, in Rosemary Rayfuse (ed.), War and the Environment: New Approaches to Protecting the Environment in Relation to Armed Conflict, Brill Nijhoff, Leiden and Boston, MA, 2014, pp. 909–910.

51 B. Sjöstedt, above note 7, p. 185.

52 ILC, Fragmentation of International Law: Difficulties Arising from the Diversification and Expansion of International Law, UN Doc. A/CN.4/L.682, 13 April 2006, para. 25.

53 B. Sjöstedt, above note 7, p. 185.

54 Biodiversity Convention, above note 15, Art. 22.

55 Convention Concerning the Protection of the World Cultural and Natural Heritage, 1037 UNTS 15, 16 November 1972 (entered into force 17 December 1975) (World Heritage Convention), Art. 6(3).

56 B. Sjöstedt, above note 7, p. 186.

57 Convention on Wetlands of International Importance Especially as Waterfowl Habitat, 996 UNTS 245, 2 February 1971 (entered into force 21 December 1975), Art. 3 (emphasis added). See also the open-ended Article II of the Convention on the Conservation of Migratory Species of Wild Animals, which provides that “[t]he Parties acknowledge the importance of … Range States … taking individually or in co-operation appropriate and necessary steps to conserve [migratory] species and their habitat”: Convention on the Conservation of Migratory Species of Wild Animals as Amended, 19 ILM (1980), 23 June 1979 (entered into force 1 November 1983), Art. II (emphasis added).

58 Nuclear Weapons Advisory Opinion, above note 39, para. 25.

59 See e.g. K. Stefanik, above note 37, p. 115.

60 See B. Sjöstedt, above note 7, p. 119.

61 See Karen Hulme, War Torn Environment: Interpreting the Legal Threshold, Martinus Nijhoff, Leiden, 2004, pp. 82–83.

62 See e.g. A. Dienelt, above note 7, p. 293; K. Stefanik, above note 37, pp. 103–104.

63 ICTY, The Prosecutor v. Tihomir Blaškić, Case No. IT-95-14-A, Judgment (Appeals Chamber), 29 July 2004, para. 639 fn. 1332.

64 SCSL, The Prosecutor v. Issa Hassan Sesay et al., Case No. SCSL-04-15-A, Judgment (Appeals Chamber), 26 October 2009, paras 577–579, esp. para. 577 in relation to IACs.

65 See International Convention against the Taking of Hostages, 1316 UNTS 205, 17 December 1979 (entered into force 3 June 1983), Art. 12.

66 Knut Dörmann, “Article 8”, in Otto Triffterer (ed.), Commentary on the Rome Statute of the International Criminal Court, Nomos Verlagsgesellschaft, Baden-Baden, 1999, p. 321.

67 See e.g. Marie G. Jacobsson, Preliminary Report on the Protection of the Environment in Relation to Armed Conflicts, UN Doc. A/CN.4/674, 30 May 2014, para. 83; B. Sjöstedt, above note 7, pp. 48, 128.

68 See below notes 69–71.

69 See e.g. ICTY, The Prosecutor v. Milorad Krnojelac, Case No. IT-97-25-T, Judgment (Trial Chamber), 15 March 2002, para. 181; ICTY, The Prosecutor v. Zejnil Delalić et al., Case No. IT-96-21-T, Judgment (Trial Chamber), 16 November 1998, paras 534–540; ICTY, The Prosecutor v. Dragoljub Kunarac et al., Case Nos IT-96-23-T, IT-96-23/1-T, Judgment (Trial Chamber), 22 February 2001, paras 519–520.

70 See e.g. ICC, The Prosecutor v. Al Hassan Ag Abdoul Aziz Ag Mohamed Ag Mahmoud, Case No. ICC-01/12-01/18-461-Corr-Red, Corrigendum to the Decision on the Confirmation of Charges (Pre-Trial Chamber), 13 November 2019, paras 378–384 as well as 483 and 492.

71 See e.g. ICRC, Commentary on the Third Geneva Convention: Convention (III) Relative to the Treatment of Prisoners of War, 2nd ed., Geneva, 2020, paras 710–731, esp. paras 715, 718, 723, 724, 728 (ICRC Commentary on GC III). For remarks that apparently confuse the “interpretation process” with the “application process”, however, see paras 94–95.

72 Although in the The Iron Rhine (“Ijzeren Rijn”) Railway Case, the Permanent Court of Arbitration (PCA) stated, in the French version, that “les normes de protection de l'environnement … peuvent s'avérer pertinentes pour l'interprétation des traités … [dans la mesure où elles sont] applicables aux relations entre les Parties” (emphasis added), the term “applicable” meant “binding” upon the parties. This is confirmed by the English version, which uses the term “relevant” rather than “applicable”. PCA, The Iron Rhine (“Ijzeren Rijn”) Railway Case (Belgium v. The Netherlands), Award, 24 May 2005, para. 60, French version available at: https://pcacases.com/web/sendAttach/481; English version available at: https://pcacases.com/web/sendAttach/478.

73 See e.g. ICTY, Kunarac, above note 69, para. 496. In earlier cases, the Tribunal extended that requirement to both State and non-State parties (see e.g. ICTY, Delalić, above note 69, para. 473; ICTY, The Prosecutor v. Anto Furundžija, Case No. IT-95-17-1-T, Judgment (Trial Chamber), 10 December 1998, para. 162). In that sense, the ICRC position in favour of the incorporation of certain IHRL fair trial guarantees in Article 3 common to the four Geneva Conventions of 1949, but only on the side of the State and not the non-State party, seems misleading (see ICRC Commentary on GC III, above note 71, para. 715). This is indeed contrary to the principle of equality between belligerents.

74 See e.g. R. van Steenberghe, “The Impacts of Human Rights Law on the Regulation of Armed Conflict: A Coherency-Based Approach to Dealing with both the ‘Interpretation’ and ‘Application’ Processes”, International Review of the Red Cross, Vol. 104, No. 919, 2022, pp. 1377–1378. On that incorporation of IHRL into IHL for the purpose of defining the war crime of sentencing without due process, see e.g. Katharine Fortin, “The Procedural Right to a Remedy When the State has Left the Building? A Reflection on Armed Groups, Courts and Domestic Law”, Journal of Human Rights Practice, Vol. 14, No. 2, 2022, p. 407.

75 ICC, Al Hassan, above note 70, para. 384.

76 See e.g. Phoebe N. Okowa, “Natural Resources in Situations of Armed Conflict: Is There a Coherent Framework for Protection?”, International Community Law Review, Vol. 9, No. 3, 2007, p. 249.

77 As emphasized by States during the ILC's work on the protection of the environment in relation to armed conflicts (see comments by France in ILC, below note 80, p. 81), there is no admitted definition of that concept under international law.

78 For indistinct references to those three statements with respect to different issues, see in particular ILC Commentaries, above note 6, fn. 593, 626, 650, 655, 744, 748.

79 Nuclear Weapons Advisory Opinion, above note 39, para. 30.

80 See e.g. ILC, Protection of the Environment in Relation to Armed Conflicts: Comments and Observations Received from Governments, International Organizations and Others, UN Doc. A/CN.4/749, 17 January 2022, p. 88 for Israel and p. 89 for the United States.

81 Nuclear Weapons Advisory Opinion, above note 39, para. 32.

82 Ibid., para. 33.

83 R. van Steenberghe, above note 74, p. 1132.

84 For a comprehensive study of this type of interpretation, see e.g. Georges Abi-Saab, Kenneth Keith, Gabrielle Marceau and Clément Marquet (eds), Evolutionary Interpretation and International Law, Hart, Oxford, 2020.

85 ILC, above note 80, p. 181.

86 See e.g. comments by France in ibid., p. 81.

87 Protection of the Environment in Relation to Armed Conflicts: Text and Titles of the Draft Principles Provisionally Adopted by the Drafting Committee on First Reading, UN Doc. A/CN.4/L.937, 6 June 2019, Draft Principle 15.

88 PERAC Principles, above note 30, Principle 14.

89 Conference of Experts, above note 11, paras 9, 11 (emphasis added).

90 UNGA Res. 47/37, 25 November 1992, Preamble.

91 Nuclear Weapons Advisory Opinion, above note 39, para. 32 (emphasis added).

92 Karen Hulme, “Taking Care to Protect the Environment against Damage: A Meaningless Obligation?”, International Review of the Red Cross, Vol. 92, No. 879, 2010, p. 678.

93 See e.g. Cordula Droege and Marie-Louise Tougas, “The Protection of the Natural Environment in Armed Conflict – Existing Rules and Need for Further Legal Protection”, in R. Rayfuse (ed.), above note 50, pp. 21–23. See also ICRC, above note 5, sections 117–118.

94 See e.g. ILC Commentaries, above note 6, p. 136, para. 4.

95 See e.g. J. d'Aspremont, above note 12, p. 17 fn. 82.

96 See B. Sjöstedt, above note 7, pp. 192–195. See also Dienelt's reflections on those objections, in A. Dienelt, above note 7, pp. 222, 281

97 Admittedly, in the Hassan case, the ECtHR resorted to the principle of systemic integration to solve a genuine conflict of norms (ECtHR, Hassan, above note 36, para. 102). There was a conflict between (1) Article 5 of the European Convention on Human Rights (ECHR), which allows depriving persons of their liberty only for limitative reasons and which subjects such deprivation of liberty to judicial review, and (2) the IHL rules applicable to prisoners of war and civilian internees in IACs, which permit the detention of those persons for security reasons and do not subject that detention to any review with respect to prisoners of war or provide the possibility for non-judicial review regarding the detention of civilians. The Court gave priority to the IHL rules and presented this outcome as the result of an interpretation of Article 5 in light of those IHL rules, on the basis of the principle of systemic integration (ibid., paras 108–111). However, this was highly criticized both by certain judges of the Court (see e.g. ibid., Partly Dissenting Opinion of Judge Spano, Joined by Judges Nicolaou and Kalaydjieva, pp. 65–66, para. 18) and by scholars (see e.g. Marko Milanovic, “A Norm Conflict Perspective on the Relationship between International Humanitarian Law and Human Rights Law”, Journal of Conflict and Security Law, Vol. 14, No. 3, 2010, p. 475), who emphasized that the Court's reasoning actually involved rewriting the ECHR.

98 On that requirement, see e.g. Ulf Linderfalk, “Who are ‘the Parties’? Article 31, Paragraph 3(c) of the 1969 Vienna Convention and the ‘Principle of Systemic Integration’ Revisited”, Netherlands International Law Review, Vol. 55, No. 3, 2008.

99 See e.g. B. Sjöstedt, above note 7, p. 195.

100 See e.g. Campbell McLachlan, “The Principle of Systemic Integration and Article 31(3)(c) of the Vienna Convention”, International and Comparative Law Quarterly, Vol. 54, 2005, pp. 314–315.

101 UN Conference on Environment and Development, “Agenda 21”, Rio de Janeiro, 3–14 June 1992, available at: https://sustainabledevelopment.un.org/content/documents/Agenda21.pdf.

102 See World Trade Organization (WTO), United States - Import Prohibition of Certain Shrimp and Shrimp Products, WT/DS58/AB/R, DSR 1998:VII, 12 October 1998, pp. 2793–2798, para. 130.

103 Cartagena Protocol on Biosafety to the Convention on Biological Diversity, 2226 UNTS 208, 29 January 2000 (entered into force 11 September 2003), Art. 10(6).

104 See e.g. D. Dam-de Jong, above note 50, p. 210.

105 See e.g. statements from Belarus (UN Doc. A/C.6/70/SR.24, 4 December 2015, para. 15); Greece (UN Doc. A/C.6/71/SR.29, 2 December 2016, para. 17); the United States (UN Doc. A/C.6/73/SR.29, 10 December 2018, para. 41); and South Africa (UN Doc. A/C.6/73/SR.30, 6 December 2018, para. 3).

106 B. Sjöstedt, above note 7, pp. 166–169; A. Dienelt, above note 7, pp. 278–279.

107 B. Sjöstedt, above note 7, pp. 163–166.

108 See e.g. the case law mentioned in R. van Steenberghe, above note 74, pp. 1362–1363 fn. 112.

109 See e.g. ILC, above note 52, para. 18.

110 See e.g. Gloria Gaggioli, L'influence mutuelle entre les droits de l'homme et le droit international humanitaire à la lumière du droit à la vie, Pedone, Paris, 2013, p. 59.

111 ILC, above note 52, para. 56.

112 Ibid., paras 413–414.

113 B. Sjöstedt, above note 7, p. 167; A. Dienelt, above note 7, p. 279.

114 M. Lehto, above note 6, para. 245. See also, as examples of interpreting the law of occupation in light of subsequent legal developments, PERAC Principles, above note 30, Principles 19, 20.

115 See e.g. WTO, above note 102, paras 134 and 158, footnote 157; PCA, above note 72, paras 59 and 79; ICJ, Legal Consequences for States of the Continued Presence of South Africa in Namibia (South West Africa) notwithstanding Security Council Resolution 276 (1970), Advisory Opinion, ICJ Reports 1971, para. 53 (as interpreted by scholars as applying the principle of systemic integration: see e.g. Ian Sinclair, The Vienna Convention on the Law of Treaties, Manchester University Press, Manchester, 1984, p. 140).

116 See e.g. B. Sjöstedt, above note 7, pp. 46, 164; D. Dam-de Jong, above note 50, p. 210.

117 See e.g. Ulf Linderfalk, On the Interpretation of Treaties: The Modern International Law as Expressed in the 1969 Vienna Convention on the Law of Treaties, Springer, Dordrecht, 2007, pp. 64–73.

118 See e.g. ICJ, Kasikili/Sedudu Island (Botswana v. Namibia), Judgment, ICJ Reports 1999, para. 27; International Centre for Settlement of Investment Disputes, Asian Agricultural Products Ltd v. Republic of Sri Lanka, Award, 27 June 1990, International Law Report, Vol. 106, para. 47.

119 For interpretations of the notion of “environment” in light of an IEL instrument, see e.g. above note 67.

120 U. Linderfalk, above note 117, pp. 70–73.

121 The Martens Clause provides that “in cases not covered by the law in force, the human person remains under the protection of the principles of humanity and the dictates of the public conscience”: see AP I, Art. 1. See also Convention (IV) respecting the Laws and Customs of War on Land and its Annex: Regulations Concerning the Laws and Customs of War on Land, 18 October 1907 (entered into force 26 January 1910), Preamble, available at: https://ihl-databases.icrc.org/en/ihl-treaties/hague-conv-iv-1907; Geneva Convention (I) for the Amelioration of the Condition of the Wounded and Sick in Armed Forces in the Field of 12 August 1949, 75 UNTS 31 (entered into force 21 October 1950), Art. 63; Geneva Convention (II) for the Amelioration of the Condition of Wounded, Sick and Shipwrecked Members of Armed Forces at Sea of 12 August 1949, 75 UNTS 85 (entered into force 21 October 1950), Art. 62; Geneva Convention (III) relative to the Treatment of Prisoners of War of 12 August 1949, 75 UNTS 135 (entered into force 21 October 1950), Art. 142; Geneva Convention (IV) relative to the Protection of Civilian Persons in Time of War of 12 August 1949, 75 UNTS 287 (entered into force 21 October 1950) (GC IV), Art. 158; Protocol Additional (II) to the Geneva Conventions of 12 August 1949 and relating to the Protection of Victims of Non-International Armed Conflicts, 1125 UNTS 609, 8 June 1977 (entered into force 7 December 1978), Preamble.

122 See e.g. ICRC, above note 5, p. 80; PERAC Principles, above note 30, Principle 12.

123 B. Sjöstedt, above note 7, p. 118.

124 Ibid., pp. 119–120.

125 See e.g. Antonio Cassese, “The Martens Clause: Half a Loaf or Simply Pie in the Sky?”, European Journal of International Law, Vol. 11, No.1, 2000.

126 See e.g. Joseph Raz, “Legal Principles and the Limits of Law”, Yale Journal of International Law, Vol. 81, 1972, p. 841.

127 K. Stefanik, above note 37, pp. 102–115.

128 B. Sjöstedt, above note 7, esp. pp. 175–212; A. Dienelt, above note 7.

129 B. Sjöstedt, above note 7, esp. pp. 175–212.

130 A. Dienelt, above note 7.

131 B. Sjöstedt, above note 7, pp. 197–206.

132 Ibid., pp. 46, 164, 168–169.

133 Ibid., p. 194.

134 See e.g. the case law mentioned in R. van Steenberghe, above note 74, pp. 1362–1363 fn. 112.

135 See WTO, above note 102, para. 130.

136 See e.g. M. N. Schmitt, above note 17, p. 50; Daniel Bodansky, The Art and Craft of International Environmental Law, Harvard University Press, Cambridge, MA, 2010, p. 226; Anthony Leibler, “Deliberate Wartime Environmental Damage”, California Western International Law Journal, Vol. 23, No. 1, 1992, p. 80; A. L. Bunker, above note 19, p. 211.

137 B. Sjöstedt, above note 7, pp. 206–207.

138 Ibid., p. 207.

139 Moreover, this process intriguingly looks like an application of the lex specialis principle as is done by IHRL bodies when interpreting an applicable IHRL norm in light of IHL. Yet, this principle has been considered as inapplicable under the reconciliatory approach.

140 A. Dienelt, above note 7, p. 277.

141 Ibid., pp. 14–15, 281, 293.

142 Ibid., pp. 14–15, 281, 297.

143 Ibid., pp. 282–297.

144 Ibid., pp. 298–318.

145 Ibid., pp. 15, 281, 293, 297.

146 Ibid., pp. 15–16, 298, 312, 317.

147 Ibid., p. 317; see also pp. 15–16.

148 Ibid., pp. 314–316.

149 Anne Peters, “The Refinement of International Law: From Fragmentation to Regime Interaction and Politicization”, International Journal of Constitutional Law, Vol. 15, No. 3, 2017.

150 Alexander Proelβ, Internationales Umweltrecht, De Gruyter, Berlin, 2017.

151 Gunther Teubner, Constitutional Fragments: Societal Constitutionalism and Globalization, Oxford University Press, Oxford, 2012.

152 A. Dienelt, above note 7, p. 316.

153 Ibid., pp. 281, 293–294, 297, 314.

154 Ibid., pp. 281, 294.

155 See ibid., pp. 298–318.

156 See ibid., p. 317; see also pp. 15–16.

157 ibid., p. 318 (emphasis added).

158 For the application of such an approach to IHL–IHRL interplay, see R. van Steenberghe, above note 74, pp. 1368–1396.

159 B. Sjöstedt, above note 7, pp. 189–191.

160 See e.g. Bobbio, Norberto, Teoria dell'Ordinamento Giuridico, G. Giappichelli Ed., Torino, 1960, esp. pp. 69 ff.Google Scholar; Dworkin, Ronald, Law's Empire, Fontana Press, London, 1986, esp. pp. 176 ff.Google Scholar; MacCormick, Neil, “Coherence in Legal Justification”, in Peczenik, Aleksander, Lindahl, Lars and Roermund, Bert Van (eds), Theory of Legal Science: Proceedings of the Conference on Legal Theory and Philosophy of Science, Lund, December 11–14, 1983, D. Reidel Publishing Company, Dordrecht, London and Lancaster, 1984, pp. 235 ff.Google Scholar; Villa, Vittorio, “Normative Coherence and Epistemological Presuppositions of Justification”, in Nerhot, Patrick (ed.), Law, Interpretation and Reality, Kluwer, Dordrecht, Boston, MA and London, 1990, pp. 430 ff.Google Scholar; Schiavello, Aldo, “On ‘Coherence’ and ‘Law’: An Analysis of Different Models”, Ratio Juris, Vol. 14, No. 2, 2001, pp. 233 ff.CrossRefGoogle Scholar; Amaya, Amalia, “Ten Theses on Coherence in Law”, in Araszkiewicz, Michael and Savelka, Jaromir (eds), Coherence: Insights from Philosophy, Jurisprudence and Artificial Intelligence, Springer, Dordrecht, 2013, pp. 257–260Google Scholar.

161 See e.g. Delmas-Marty, Mireille, Ordering Pluralism: A Conceptual Framework for Understanding the Transnational Legal World, Hart, Oxford and Portland, OR, 2009Google Scholar.

162 Regarding IHL–IHRL interplay, see R. van Steenberghe, above note 74, pp. 1365–1373; regarding IHL–IEL interplay, see R. van Steenberghe, above note 45, pp. 1150–1154.

163 See e.g. R. van Steenberghe, above note 74, pp. 1333–1395.

164 See e.g. most substantial provisions of the Biodiversity Convention, above note 15.

165 The identification of the lex specialis should be determined on a case-by-case basis, in light of the above-mentioned substantial considerations. Regarding IHL–IHRL interplay, there is for example growing support for considering IHRL as constituting the lex specialis in certain cases of use of lethal force and as prevailing over the competing IHL framework: see e.g. Kretzmer, David, Ben-Yehuda, Aviad and Furth, Meirav, “‘Thou Shall Not Kill’: The Use of Lethal Force in Non-International Armed Conflicts”, Israel Law Review, Vol. 47, No. 2, 2014, pp. 191 ffCrossRefGoogle Scholar.

166 Such combination of those processes is in fact already observable in IHRL case law. In the Hassan case, the ECtHR applied Article 5 of the ECHR but displaced its content in favour of the relevant IHL regime on detention (ECtHR, Hassan, above note 36). This follows the logic of the application process. However, by the same token, the Court used IHRL and, in particular, the ECHR to inform the IHL rule according to which detention must be subject to review by “a competent body”. As a result of that interpretation process, the Court strengthened the protection of civilian internees by requiring notably that such a body must “provide sufficient guarantees of impartiality and fair procedure to protect against arbitrariness” (ibid., para. 106).

167 See e.g. statements from the United Kingdom (UN Doc. A/C.6/71/SR.28, para. 25; UN Doc. A/C.6/73/SR.30, para. 9); the Netherlands (UN Doc. A/C.6/72/SR.26, para. 37); and Azerbaijan (UN Doc. A/C.6/73/SR.29, para. 114).