“Mindful also of the precautionary measures for the protection of the ozone layer which have already been taken at the national and international levels”
Inclusion of the present sentence into the Vienna Convention is significant in a sense that it boosted the use of a term in later international instruments. Even more, the wording in the treaties to follow became stronger and expressed the global concern of precautionary measures. This statement can be supported by looking at the Montreal Protocol of 1987 where it was noted the certain precautionary measures should be considered to control emission from certain chlorofluorocarbons (CFCs) at the national and international levels. Moreover, the amendments to the Montreal Protocol which took place in 1990 granted the parties determination “to protect the ozone layer by taking precautionary measures to control equitably total global emissions of substances that deplete it.” This wording in the Protocol and subsequent amendments was the first time ever when such measures were expressed to be the basis for adopting these international measures. In expanding the scope of the treaties which empower the precautionary principle it is plausible to notice that in 1987 the Ministerial Declaration of the Second North Sea Conference it was held that precautionary approach is necessary in order to avoid the harmful effects of the substances being dumped into the sea. Following years produced few documents where the present approach was highlighted. Finally, the 1990 Bergen Ministerial Declaration on Sustainable Development in the ECE Region was the first international act to state the principle being linked to sustainable development. This declaration reads as follows:
“In order to achieve sustainable development, policies must be based on the precautionary principle. Environmental measures must anticipate, attack and prevent the causes of environmental degradation. Where there are threats of serious or irreversible damage, lack of full scientific evidence should not be used as a reason for postponing measures to prevent environmental degradation.”
The most important part which defines the core of the precautionary principle is that “lack of full scientific evidence should not be used as a reason for postponing measures to prevent environmental degradation” In general terms this provision opened the gates for inclusion of the precautionary principle in many more international treaties. It is especially important that precautionary principle was used in the 1992 Biodiversity Convention and 1992 Climate change Convention which deal with the global issues of the environment. Series of other conventions such as the 1991 Bamako Convention, the 1992 UN/ECE Transboundary Watercourses Convention, the 1992 OSPAR Marine Environment Convention and the 1992 Baltic Sea Convention were quick to adopt the principle. The Article 3(2) of the 1992 Baltic Sea Convention states that “the Contracting Parties shall apply the precautionary principle, i.e., to take preventive measures when there is reason to assume that substances or energy introduced, directly or indirectly, into the marine environment may create hazards to human health, harm living resources and marine ecosystems, damage amenities or interfere with other legitimate uses of the sea even when there is no conclusive evidence of a causal relationship between inputs and measures referred to in paragraphs 1 and 2 of this article, the Parties shall be guided by the following principles: a) The precautionary principle, by virtue of which action to avoid the potential Transboundary impact of the release of hazardous substances shall not be postponed on the ground that scientific research has not fully proved a causal link between those substances, on the one hand, and the potential transboundary impact, on another hand.” Hence, the wording in the present convention suggests that the precautionary approach was taken very seriously in the region of the Baltic Sea. Consequently, all the nine countries bordering the Baltic Sea including Denmark, Germany, Sweden, Estonia, Finland, Latvia, Lithuania, Poland and Russia signed and ratified the convention.
The introduction of the principle in various environmental treaties plays a significant part in the process of the precautionary principle gaining more weight in the international law. But the most important aspect of this approach is the role that it played in the 1992 UNCED Conference in Rio de Janeiro. Foremost must be its specific inclusion as Principle 15 of the 1992 Rio Declaration, which reads:
“In order to protect the environment, the precautionary approach shall be widely applied by States according to their capabilities. Where there are threats of serious or irreversible damage lack of full scientific certainty shall not be used as a reason for postponing cost-effective measures to prevent environmental degradation.” As it was mentioned previously, both conventions, UN Framework Convention on Climate Change and Convention on Biological Diversity, emerging from Rio, contain the precautionary principle. Moreover, the principle is found in Agenda 21 and in particular in Chapter 17.01 on Protection of the Oceans, which expressly insists ‘new approaches to marine and coastal area management and development at the national subregional, regional and global levels, approaches that are integrated in content and are precautionary and anticipatory in ambit…’ Hereof, the distinctive nature of precautionary principle is worth mentioning. Besides the fact that variety of measures can be used to implement it, it is unique in the way in which, and the time at which, the measure to be adopted.
The Rio Declaration, in its’ very least effect initiates the precautionary thinking in various international law instruments. However, even though the declaration is ratified by a large number of countries it is not binding in nature. It must be said that “the precautionary principle is now an important instrument for providing guidance to states and the international community in the development of international environmental law and policy in the face of scientific uncertainty…” Nevertheless, it would be too early to treat this instrument as a part of customary international law because the status of precautionary principle is still questionable. From here we need to look at the case law regarding the precautionary principle as the rule of customary international law and analyze the standards that a principle must meet in order to become a part of the customary international law.
Case Law
The continuing discussion among scholars as to whether precaution is a legal or simply a policy principle leads us to nowhere unless a precise look at the International Court of Justice cases involving the principle is being afforded. Hence, in the case of the Gabcikovo – Nagymaros, Judge Weeramantry in his separate opinion views the principle as a constituent part of the winder legal principle of sustainable development. By addressing the issue of sustainable development Judge Weeramantry states that both the right to development and the right to environmental protection are principles currently forming part of the corpus of international law. Furthermore, Judge continues addressing the issue and states that both principles mentioned above could operate in collision with each other unless there was a principle of international law which indicated how they should be reconciled. Hence, he notes that such principle is the principle of sustainable development which, according to his opinion, is more than a mere concept, but is itself a recognized principle of contemporary international law. It is worth mentioning that the court in deciding the case treats the precautionary principle as an applying rule in this instance. And in its’ judgment states that it “recognizes that both Parties agree on the need to take environmental concerns seriously and to take the required precautionary measures, but they fundamentally disagree on the consequences this has for the joint Project.” The wording, such as required precautionary measures brings the approach closer to being a rule instead of principle.
Another important case, concerned with the precautionary principle is the WTO decision on EU Compliance on Beef Imports from the USA. However this decision is not a positive one with regards to the precautionary principle. In this case the panel report found that the EU ban is not based on scientific evidence and is not based on a risk assessment or on the relevant international standards. Evidently, the Panels decision is contrary to the precautionary principle in its very nature, because one of the defining parts of precautionary approach is the fact that “lack of full scientific certainty shall not be used as a reason for postponing cost-effective measures to prevent environmental degradation” Thus, it can be reaffirmed that the opinions on the present principle are very variable and the idea needs to be developed further in order to become a rule of customary international law.
Customary International Law and State Practice of the Rule of Law
In order to understand the status of the precautionary principle in the international law, one needs to explain the status of that law itself. I will try to answer the question of what is the customary international law and what are the criteria for the rule to become a part of customary international law.
The traditional doctrine explaining the customary international rules claims that a mere fact of consistent international practice is not enough to create a rule of law in the sense of the practice. Hence an additional element is required. Customary rules result from the combination of two elements: “an established, widespread, and consistent practice on the part of States; and a psychological element known as the opinio juris sive necessitatis (opinion as to law or necessity).” Very good example on this point is the ICJ judgment in the North Sea Continental Shelf case where the process by which a treaty provision might generate a rule of customary law is discussed. It reads from the judgment of this case that “not only must the acts concerned amount to a settled practice, but they must also be such, or be carried out in such a way, as to be evidence of a belief that this practice is rendered obligatory by the existence of a rule of law requiring it. The need for such a belief, i.e., the existence of a subjective element, is implicit in the very notion of the opinio juris sive necessitatis”
In this point the paradox is being reached where the implication suggests that in order for the rule to constitute customary law such rule must be practiced by the States. Hence, the question arises of how a state practices such rule which is not a rule of customary law before it does so. It is known that the precautionary principle is widely applied within the domestic levels of legislation. It has become a part of the European Union’s legislative process with regards to Environmental laws. The principle is expressed in the Community’s Treaty provision under the Title of Environment. Article 174(2) reads: “Community policy on the environment shall aim at a high level of protection taking into account the diversity of situations in the various regions of the Community. It shall be based on the precautionary principle and on the principles that preventive action should be taken, that environmental damage should as a priority be rectified at source and that the polluter should pay. Environmental protection requirements must be integrated into the Community's other policies.” Besides that, few directives and regulations on the environment regard the precautionary principle as an essential part of Environmental policy. Moreover, countries like Australia have been a very cautious with implementation of this principle. It was in 1993, when Justice Stein’s seminal Leatch decision began the process of recognition and acceptance of the principle in Australian Law. Subsequently, the principle has been incorporated in Australian Environmental Statutes and it continues to date to have the potential to become a central feature of Australian environmental law and policy. Nonetheless, international law is a creature of constructed obligations, which are norms essentially accepted by states for participation in the international community. If states adopt the precautionary principle, they choose to contract an obligation – a new norm of international law. Consequently, it can be claimed that at least among the developed states this principle is common and widely spread. On the contrary, it is not accepted by all the international community and moreover, another, psychological element of opinio juris needs to be met. Evidently, it is clear that the precautionary principle even though being applied in many national jurisdictions, does not meet uniformity and international consensus in order to be regarded as the rule of customary international law.
Conclusion
From the foregoing follows that the precautionary principle is a relatively new principle in international environmental law and has not yet become a rule of customary international law. Nevertheless, the evolution of precautionary principle over the years proved that the principle plays a significant role in international environmental law. Firstly, environmental policy making shifted from traditional tort mechanism, where the harm is being assessed only after its occurrence to a more applying mechanism in this area, such as the use of precaution. Furthermore, even though the universal definition doesn’t exist it has been agreed that the lack of scientific evidence should not be used as a reason for postponing measures to prevent environmental degradation. Moreover, the burden of proof has been shifted upon those who seek to continue the potentially harmful practice, which brings the states to be more cautious of their carried out activities. Finally, the principle initiated the emergence of new environmental regulations thus strengthening the law itself and bringing it closer to legally binding policies.
Substantially, there are several international treaties, national legislation acts and international case law embodying and specifying the precautionary principle. It gained more weight in the arena of international law after it was unanimously endorsed in Rio Declaration of 1992. Because this international instrument is widely ratified by states, the precautionary approach commenced a new level of impact upon the national legislations of these states. Besides inclusion of the precautionary principle in Rio Declaration of 1992, it became a part of most international environmental treaties, which proves that the principle is no longer an idea, but rather the rule which will eventually evolve into the rule of customary law. The opinion expressed by Judge Weeramantry in the ICJ decision where he treats the principle as interconnected part of sustainable development which is a rule of international law, strengthens the position of the principle in the international law to wider extent.
Although the principle does not meet the requirements to be accepted as the rule of customary international law, it has strong implications of becoming one in a short period of time.
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