See, inter alia, D. Bodansky, ‘Deconstructing the Precautionary Principle’, in: D.D. Caron and H.N. Scheiber (eds.), Bringing New Law to Ocean Waters (Brill, 2004), 381, at 382.
It has been included in numerous multilateral environmental agreements (MEAs). See A. Trouwborst, Evolution and Status of the Precautionary Principle in International Law (Kluwer Law International, 2002), at 63ff.
Rio Declaration on Environment and Development, in Report of the UN Conference on Environment and Development (UN Doc. A/CONF.151/26/Rev. 1 (Vol. I), 14 June 1992), Annex, Principle 15.
See A. Trouwborst, n. 2 above, at 362.
For a deconstruction of the principle, see D. Bodansky, n. 1 above, at 389–391; and ‘Reconstructing Precaution, Deconstructing Misconceptions’, 21:3 Ethics and International Affairs (2007), 359. ,
The PP is ‘only’ mentioned with regard to oceans and seas in the main outcome document of the conference. See United Nations Conference on Sustainable Development, The Future We Want (UN Doc. A/CONF.216/L.1, 19 June 2012), at paragraphs 158 and 167.
The term ‘decision making’ is understood here as including not only decision making in individual cases, but also policy making in certain instances. Although it can also be framed as decision making, dispute settlement by (quasi-)judicial bodies is not included in this term for the purposes of this article. ‘Decision making’ has also been referred to as ‘implementation’. See, e.g., ‘The Precautionary Principle in General International Law: Combating the Babylonian Confusion’, 16:2 Review of European Community and International Environmental Law (2007), 185, at 192. ,
Arguably, the strong opposition of accepting a ‘shift’ in the allocation of the BoP stems from seeing this ‘shift’ as creating a very low standard of proof. See, e.g., J.S. Gray, ‘Integrating Precautionary Scientific Methods into Decision-making’, in: D. Freestone and E. Hey (eds.), The Precautionary Principle and International Law (Kluwer Law International, 1996), 133, at 136.
T. Franck, Fairness in International Law and Institutions (Oxford University Press, 1998).
‘Tom Franck's Fairness’, 13:4 European Journal of International Law (2002), 909, at 910. ,
For considering ‘procedural fairness’ as a basis for allocating the BoP in precaution-related cases, see C. Foster, Science and the Precautionary Principle in International Courts and Tribunals: Expert Evidence, Burden of Proof and Finality (Cambridge University Press, 2011), at 240–241; ‘International Adjudication – Standard of Review and Burden of Proof: Australia-Apples and Whaling in the Antarctic’, 21:2 Review of European Community and International Environmental Law (2012), 80, at 86. Although put in different terms, Hepburn , et al. also argued that: ‘The distribution of risk is also important, as harms rarely fall equally on those affected. Perhaps most important, due to precaution, the reversal of the BoP means that proponents of risky activities need to take potential impacts into account in their planning, without leaving this aspect solely to those who will be most affected.’ See J. Hepburn, with M.-C. Cordonier Segger and M. Gehring, The Principle of the Precautionary Approach to Human Health, Natural Resources and Ecosystems (Center for International Sustainable Development Law, 2005), at 4.
In other fields of law, where the PP is applied to protect other interests (e.g., health), fairness needs to be assessed in the light of that particular protected aim of the principle. Arguably, however, the analysis provided here equally applies to those areas.
ICJ 20 April 2010, Pulp Mills on the River Uruguay (Argentina v. Uruguay),  ICJ Rep. 14 (Pulp Mills).
ICJ 25 September 1997, Gabčíkovo-Nagymaros Project (Hungary v. Slovakia),  ICJ Rep. 7 (Gabčíkovo-Nagymaros).
WTO DS 18 August 1997, EC – Measures Concerning Meat and Meat Products, WT/DS26/R/USA (EC-Hormones, Panel); WTO AB 16 January 1998, EC – Measures Concerning Meat and Meat Products, WT/DS26/AB/R (EC-Hormones).
On the applicability of the PP to health-related issues see, inter alia, International Law Association, ILA New Delhi Declaration of Principles of International Law Relating to Sustainable Development (UN Doc. A/CONF.199/8, 9 August 2002); Communication from the Commission of 2 February 2000 on the Precautionary Principle, COM (2000)1 final.
See J.B. Wiener, ‘Precaution’, in: D. Bodansky, J. Brunnée and E. Hey (eds.), The Oxford Handbook of International Environmental Law (Oxford University Press, 2007), 597, at 599. For the development of the PP, see D. Freestone and E. Hey, ‘Origins and Development of the Precautionary Principle’, in: D. Freestone and E. Hey (eds.), n. 8 above, 3, at 3–15; J. Cameron and J. Abouchar, ‘The Status of the Precautionary Principle in International Law’, in: D. Freestone and E. Hey (eds.), n. 8 above, 29 and W.Th. Douma, The Precautionary Principle: Its Application in International, European and Dutch Law, PhD Thesis (2002).
See J.B. Wiener, n. 17 above, at 601.
Ibid. See also Gabčíkovo-Nagymaros, n. 14 above; Pulp Mills n. 13 above; EC-Hormones, n. 15 above.
‘Considerations Regarding the Hormones Case, the Precautionary Principle and International Dispute Settlement Procedures’, 13:1 Leiden Journal of International Law (2000), 239, at 244; J.B. Wiener, n. 17 above, at 598. ,
C. Tinker, ‘State Responsibility and the Precautionary Principle’, in: D. Freestone and E. Hey (eds.), n. 8 above, 53, at 70.
On the importance of the underlying ‘theories of administrative constitutionalism’ for the interpretation of the PP, see E. Fisher and R. Harding, ‘The Precautionary Principle and Administrative Constitutionalism: The Development of Frameworks for Applying the Precautionary Principle’, in: E. Fisher, J. Jones and R. von Schomberg (eds.), Implementing the Precautionary Principle: Perspectives and Prospects (Edward Elgar, 2006), 113.
Rio Declaration, n. 3 above, Principle 15. See also the Bergen Declaration of Ministers, reproduced in: R. Churchill and D. Freestone (eds.), International Law and Global Climate Change (Springer, 1991), at 344.
Compare with D. Bodansky, n. 1 above, at 383–386.
For a clear opposition of this third version, see ‘The Precautionary Principle in International Law: Lessons from Fuller's Internal Morality’, 49:3 McGill Law Journal (2004), 779, at 782–783. and ,
See also A. Trouwborst, n. 7 above, at 191–192.
See J.B. Wiener, n. 17 above, at 604–606. See also C. Tinker, n. 21 above, at 55–56; D. Bodansky, n. 1 above, at 390–391; and ‘The Precautionary Principle: A European Perspective’, 6:3 Human and Ecological Risk Assessment (2000), 445, at 448. ,
This position is contrary to the generally accepted view, which holds that ‘[s]ome versions of the precautionary approach would reverse’ the traditional allocation of the BoP. D. Bodansky, n. 1 above, at 390–391 (emphasis added). See also C. Tinker, n. 21 above, at 55–56; ‘Regulatory Design for Scientific Uncertainty: Acknowledging the Diversity of Approaches in Environmental Regulation and Public Administration’, 19:3 Journal of Environmental Law (2007), 347, at 354–355; , ‘Rescuing the Strong Precautionary Principle from Its Critics’, 2011:4 University of Illinois Law Review (2011), 1285. The position taken in this article seems to be supported by Trouwborst, who discussed the three legs of the PP, with the third leg being precautionary action which incorporates the BoP rules. However, he also explains that the ‘shift’ in the BoP is not always applied. A. Trouwborst, n. 7 above, at 192. ,
For acknowledging this distinction between a ‘claim’ and ‘exception’, and the difficulties surrounding exceptions, see also C. Foster, Science and the Precautionary Principle, n. 11 above, at 244; and C. Foster, ‘International Adjudication – Standard of Review and Burden of Proof’, n. 11 above, at 87.
Pulp Mills, n. 13 above.
Although it has been argued in the context of State responsibility that it is difficult to establish ‘the existence of a clear legal duty or obligation’, the article proceeds on the basis of the understanding that a substantive understanding can be attached to the concept, and focuses only on the procedural consequence of PP as obligation. In other words, seeing PP as an obligation in this context is relevant for the discussion on the PP's procedural aspect, but this discussion does not seek to assess whether or not indeed there is a clear obligation established by the PP or determine its possible content. See C. Tinker, n. 21 above, at 57.
Pulp Mills, n. 13 above, at paragraph 170 (emphasis added). See also ibid., Separate Opinion of Judge Cançado Trindane, at paragraph 108.
Although not formulated in such terms, the argument of Hepburn et al. also refers to precaution in the form of justification. In their view, ‘precaution shifts the burden of proof from those proposing measures that will reduce uncertain risks to these systems, to those supporting development’. See J. Hepburn, with M.-C. Cordonier Segger and M. Gehring, n. 11 above, at 5. See also L. Hancher, ‘EC Environmental Policy: A Pre-cautionary Tale?’, in: D. Freestone and E. Hey (eds.), n. 8 above, 187, at 202–203.
Gabčikovo-Nagymaros, n. 14 above. On the application of the PP by the ICJ in the Gabčikovo-Nagymaros case, see also W.Th. Douma, n. 17 above, at 164–171.
EC-Hormones, n. 15 above. On the application of the PP in this case, see also W.Th. Douma, n. 17 above, at 184.
EC-Hormones, Panel, n. 15 above, at paragraph 184.
Gabčikovo-Nagymaros, n. 14 above, at paragraph 40. It was referred to as a ‘state of ecological necessity’.
J. Kokott, The Burden of Proof in Comparative and International Human Rights Law: Civil and Common Law Approaches with Special Reference to the American and German Legal Systems (Kluwer Law International, 1998), at 9–10. See also C. Bosse, Bewijslastverdeling in het Nederlands en Belgisch Arbeidsrecht (Kluwer, 2003), at 12–14.
See J. Kokott, n. 38 above, at 9.
Ibid. See also ‘Burden and Standard of Proof in Proceeding under the European Convention’, 26:1 European Law Review (2001), 68, at 77. ,
Although scholars in general do not specify which BoP they refer to, they generally discuss the burden of persuasion. Due to the non-specification the two meanings of the BoP are often mixed, leading to uncertainty concerning the proper allocation of the BoP.
See also Bosse, n. 38 above, at 15.
Laying down rules for the allocation of the burden of production is only necessary in terms of the specific course of a particular procedure – that is, when the word is given to one or the other party.
This rule is also referred to as the rule of ei incumbit probatie qui dicit, non qui negat (‘the burden of proof lies with who declares, not who denies’).
See, inter alia, C. Bosse, n. 38 above, at 16; J. Kokott, n. 38 above, at 11; C. Foster, ‘International Adjudication – Standard of Review and Burden of Proof’, n. 11 above, at 85.
An applicant can also become respondent with regard to allegations of violating other rules by the original respondent. The discussion here focuses on one specific matter, with regard to which an applicant and a respondent can be identified.
See, inter alia, K. Monaghan, Equality Law (Oxford University Press, 2007), at 563.
See also U. Erdal, n. 40 above, at 82.
For more details, see M. Ambrus, Enforcement Mechanisms of the Racial Equality Directive and Minority Protection: Theory and Four Case Studies (Eleven International, 2011).
See, inter alia, Council Directive 97/80/EC of 15 December 1997 on the Burden of Proof in Cases of Discrimination Based on Sex (‘Burden of Proof Directive’),  OJ L14, Article 4; Council Directive 2000/43/EC of 29 June 2000 Implementing the Principle of Equal Treatment between Persons Irrespective of Racial or Ethnic Origin (‘Racial Equality Directive’),  OJ L180, Article 8.
See also J. Kokott, n. 38 above, at 2.
For a position according to which it is ‘only’ the evidential BoP which switches to the respondent see, e.g., INTERIGHTS, Written Comments in the case of Nachova and others v. Bulgaria (2005), found at: <http://www.justiceinitiative.org/db/resource2/fs/?file_id=15404>.
G. Bindman, ‘Proof and Evidence of Discrimination’, in: B.A. Hepple and E.M. Szyszczak (eds.), Discrimination: The Limits of Law (Mansell, 1992), 50, at 58 (emphasis added).
Proposal for a Council Directive Implementing the Principle of Equal Treatment between Persons Irrespective of Racial or Ethnic Origin, COM (1999)566 final, at 9. See, inter alia, ECJ, Case C-127/92, Dr Pamela Mary Enderby v. Frenchay Health Authority and Secretary of State for Health,  ECR I-5535, at paragraph 13 (Enderby).
ECJ, Case C-109/88, Handels- og Kontorfunktionærernes Forbund I Danmark v. Dansk Arbejdsgiverforening, acting on behalf of Danfoss,  ECR 3199 (Danfoss).
Ibid., at paragraph 11 (emphasis added).
Enderby, n. 54 above, at paragraph 13.
Burden of Proof Directive, n. 50 above.
Council Directive 2000/78/EC of 27 November 2000 Establishing a General Framework for Equal Treatment in Employment and Occupation,  OJ L303.
Council Directive 2004/113/EC of 13 December 2004 Implementing the Principle of Equal Treatment between Men and Women in the Access to and Supply of Goods and Services,  OJ L373; Directive 2006/54/EC of the European Parliament and of the Council of 5 July 2006 on the Implementation of the Principle of Equal Opportunities and Equal Treatment of Men and Women in Matters of Employment and Occupation (‘Recast Directive’),  OJ L 204. This latter Directive replaced the one on the BoP with effect from 15 August 2009.
See, inter alia, C. Bosse, n. 38 above, at 133–134; ‘Equality and Sex Discrimination in the European Union: Is Shifting the Burden of Proof the Answer?’, 17:2 Dickinson Journal of International Law (1999), 357, at 358. ,
‘Re-dressing the Balance of Power in Discrimination Cases: The Shift in the Burden of Proof’, 4 European Anti-Discrimination Law Review (2006), 23, at 24 (emphasis added). See also K. Monaghan, n. 47 above, at 563–564 and 571; and E. Ellis, , EU Anti-discrimination Law (Oxford University Press, 2005), at 98 and 110.
See E. Ellis, n. 62 above, at 98.
Enderby, n. 54 above, at paragraph 13 (emphasis added). See also ECHR 6 January 2005, Hoogendijk v. Netherlands, No. 58641/00.
The case law of, among others, the European Court of Human Rights on Article 14 clearly shows how important the appropriate allocation of the BoP is for the effective enforcement of human rights. See, inter alia, INTERIGHTS, n. 52 above, at 1; J. Kokott, n. 38 above, at 57; and C. Bosse, n. 38 above, at 140–141. The special allocation of the BoP is, arguably, also applied in cases other than discrimination. See, e.g., UN Human Rights Council (HRC) 2 July 1994, Mukong v. Cameroon, No. 458/1991; and UN HRC 4 December 1995, Ribitsch v. Austria, No. 18896/91, at paragraph 34. See also U. Erdal, n. 40 above.
See J. Kokott, n. 38 above, at 1 (emphasis added). See also INTERIGHTS, n. 52 above.
Burden of Proof Directive, n. 50 above, Recital (17).
Racial Equality Directive, n. 50 above, Recital (21). See also COM (1999)566 final, n. 54 above, at 9.
Pulp Mills, n. 13 above, at paragraph 101.
McIntyre labelled this request a ‘radical contention’. ‘The Proceduralisation and Growing Maturity of International Water Law’, 22:3 Journal of Environmental Law (2010), 475, at 493. ,
Pulp Mills, n. 13 above, at paragraph 162.
Ibid., Joint Dissenting Opinion of Judges Al-Khasawneh and Simma, at paragraph 22. See also C. Tinker, n. 21 above, at 54; and ‘Prevention, Precaution, Logic and Law: The Relationship between the Precautionary Principle and the Preventative Principle in International Law and Associated Questions’, 2:2 Erasmus Law Review (2009), 107. ,
‘Precautionary Pulp: Pulp Mills and the Evolving Dispute between International Tribunals over the Reach of the Precautionary Principle’, 38:2 Ecology Law Quarterly (2011), 527, at 528, 545–546. ,
In general it has been argued that State responsibility ‘best protects the rights of innocent victims of environmental harm by shifting the burden of proof of causation’. C. Tinker, n. 21 above, at 68–69. See also J. Ellis and A. FitzGerald, n. 25 above, at 783.
See also C. Foster, ‘International Adjudication – Standard of Review and Burden of Proof’, n. 11 above, at 86.
ICJ 22 September 1995, Nuclear Tests (New Zealand v. France),  ICJ Rep. 1995, Dissenting Opinion of Judge Weeramantry, at 342 (‘Nuclear Tests’).
A discussion on what a prima facie case of not being precautious means requires a separate study, and is beyond the reach of this article.
The required extent to which the lack of such risk (and thus scientific (un)certainty) should be proven depends on the substantive understanding of the PP at stake.
See O. McIntyre, n. 70 above, at 493.
Gabčikovo-Nagymaros, n. 14 above, at paragraphs 49–54. In the words of the Court: ‘would have permitted Hungary, without incurring international responsibility, to suspend and abandon works’. Ibid., at paragraph 49.
See also D. Kazhdan, n. 73 above, at 540–541.
Gabčikovo-Nagymaros, n. 14 above, at paragraph 54.
Ibid. (emphasis added).
On the (non-)application of the PP in this case, see E. Hey, n. 20 above.
EC-Hormones, n. 15 above, at section VI.
‘Allocating the Burden of Proof in WTO Dispute Settlement Proceedings’, 42:2 Cornell International Law Journal (2009), at 209; , ‘The Burden of Proof in Environmental Disputes in the WTO: Legal Aspects’, 18:2 European Energy and Environmental Law Review (2009), 112, at 116. and ,
EC-Hormones, Panel, n. 15 above, at section VIII.D.6.
EC-Hormones, n. 15 above, at section IV (emphasis added).
Ibid. See also ‘Burden of Proof, Prima Facie Case and Presumption in WTO Dispute Settlement’, 42:1 Cornell International Law Journal (2009), 24. ,
Again, depending on the underlying concept of the PP, the nature and extent of scientific uncertainty that is accepted might vary. In other words, such a BoP does not mean that the party bearing the BoP needs to prove the full absence of a risk, as indicated in general by the opponents of the special allocation of the BoP. See J. Ellis and A. FitzGerald, n. 25 above, at 797.
See also D. Freestone and E. Hey, n. 17 above, at 13. In their words, the precautionary approach would entail that ‘legal, administrative and technical procedures that facilitate the implementation of this approach must be applied and, where not available, developed’.
See E. Hey, n. 20 above.
See COM (2000)1 final, n. 16 above.
Ibid., at 20. See also D. Freestone and E. Hey, n. 17 above, at 6.
See COM(2000)1 final, n. 16 above, at 20.
That is, there is a particular level of certainty that no harm will occur.
See A. Trouwborst, n. 7 above, at 192–193.
Hey and Freestone argued that ‘the threshold of significant risk has become easier to cross, which from a legal perspective would imply that once a prima facie case is made that a risk exists, then scientific uncertainty works against the potential polluter rather than, as in the past, in his/her favor’. D. Freestone and E. Hey, n. 17 above, at 13.
Pulp Mills, n. 13 above, at paragraph 22.
See T. Franck, n. 9 above, at 477.