Is it Possible to Provide Evidence of Insufficient Evidence? The Precautionary Principle at the WTO

Abstract This Article aims to demonstrate that the WTO jurisprudence on science-related trade disputes has become imbued with a specific vision of science that has prevented any possible application of the precautionary principle. This situation is due both to the WTO's specific dispute settlement procedures and to the substantive nature of precautionary measures. Indeed, such measures' foundation on "insufficient scientific evidence" dramatically undermines the probative value of science in WTO adjudication and creates a seeming contradiction: The system requires defendants to provide legal evidence of the absence of sufficient scientific evidence. The reasoning of the Panel on the EC-Biotech case was riddled with this apparent paradox. For the first time, the US-Continued Suspension case has opened a gateway to address this fundamental issue. Table of Contents I. Introduction 154 II. The Relation between Science and Precaution at the World Trade Organization 157 A. The Sanitary and Phytosanitary Agreement 157 B. The EC-Biotech Dispute: Legal Background 158 C. The Role of Article 5.7 with Respect to Article 5.1 of the SPS Agreement 160 III. Legal and Scientific Standards of Proof 162 A. The Relationship between Sufficient Scientific Evidence and Adequate Risk Assessment 163 B. Legally Locked-In Scientific Evidence 165 IV. A Question of Rights: How to Provide Legal Evidence of Insufficient Scientific Evidence 168 V. The OS-Continued Suspension Dispute: Opening the Gateway for a New Epistemology of Science at the WTO 169 A. The Factual Background of the Hormones Dispute 170 B. How to Override Scientific Evidence 171 1. Article 5.1 of the SPS Agreement: The appropriateness of risk assessment 172 2. Article 5.7 of the SPS Agreement: How to provide legal evidence of insufficient scientific evidence 173 C. Questions Left Open 175 VI. Conclusion 177 I. Introduction The precautionary principle is an established principle of international law that is explicitly included in a number of international environmental agreements, such as the Convention on Biological Diversity1 and the United Nations Framework Convention on Climate Change,2 and is referred to in more general terms in other international agreements, such as the Marrakesh Agreement of 1994 establishing the World Trade Organization.3 Notwithstanding the frequency with which it is invoked, there exists no universally accepted statement of the precautionary principle,4 nor is there consensus about its location within the sources of international law.5 Despite this ambiguity, the precautionary principle is frequently invoked in treaties to ensure that, where there are threats of serious or irreversible damages to the environment, governments should take action even if scientific evidence of the risk is not conclusive. Indeed, the precautionary principle emerged from the concern that full scientific evidence is, for many issues of environmental law and policy, too strict a standard for undertaking action and that another form of rational justification should be found within the boundaries of science. For instance, instead of requiring that a risk be established in the form of probability before acting, its existence could be reflected upon plausible, reliable - even though not conclusive - explanations.6 Once it is established that policymakers should not forgo acting when the informing science is incomplete, it remains a matter of policy discretion to decide the form of the intervention, either through protective measures or through delaying the implementation of certain projects whose risks have not been clearly identified. …