Is the EU Courts’ toolbox to tackle scientific uncertainty sufficient?, by Mariolina Eliantonio and Michał Krajewski

As the EU Courts’ docket of legal disputes involving uncertain scientific appraisals grows, questions about how the EU judges engage with science appear. This engagement may impact our understanding of ‘legality’ in the judicial review of EU legal acts as well as the effective enforcement of EU environmental law.

Growing Expectations Towards Judicial Review and Judicial Enforcement

As the EU Courts put it increasingly often, judicial review forms part of the essence of the rule of law. The specific meaning of this concept is debated, but it is generally concerned with reducing the risk of arbitrariness in the exercise of public power by subjecting it to legal rules and procedures. Through comprehensive judicial review, the EU Courts are supposed to ‘ensure that in the interpretation and application of the Treaties the law is observed’ (Article 19(1) TEU). However, at least since the seminal cases Technische Universität Münchenof 1991 and Tetra Lavalof 2005, the standard of EU judicial review is progressively more intense. Not only is the EU judicial review supposed to verify the interpretation of applicable EU law, but it must also investigate the factual basis of legal acts. Leaving the factual basis out of the scope of judicial review would create significant space for potential arbitrariness of administrative action by EU institutions and bodies. Nowadays, the factual basis of EU administrative action frequently includes intricate and uncertain empirical appraisals, the understanding of which requires specialist knowledge or at least significant effort from laypersons. These appraisals are often made in the context of irreducible uncertainty in which the best specialists may reasonably disagree as to what should be the correct assessment or course of action. Previously, the EU Courts had only subjected such appraisals to verification of ‘manifest errors’. But, as argued by a German court which prompted the EU Courts to tighten up its standard of judicial review in Technische Universität München, the more difficult the scientific or technical question underlying the contested legal act, the more immune from challenge this act would be, which weakens the rule of law and effective judicial protection. Nowadays, the EU Courts subject such complex appraisals to a so-called ‘process-oriented review’ in which they check whether the challenged EU bodies have taken into careful consideration all the relevant empirical factors, among other things.

Significant challenges are also posed by infringement proceedings in which the Court of Justice decides on breaches of EU law, especially in environmental law, based on scientific appraisals presented by the Commission. When the Commission and the Member State disagree on the interpretation of scientific data or their relevance, the Court of Justice may be called to tackle a scientific issue or try to navigate around it. The ability of the Court to handle scientific problems seems increasingly more pressing in the context of environmental law enforcement. Otherwise, the Commission may get discouraged from bringing infringement cases that it cannot support by foolproof evidence. However, it should be recalled that in obtaining such evidence, the Commission – bereft of independent investigatory forces – remains dependent on the cooperation with the concerned Member States, their fulfilment of monitoring obligations, as well as the information provided by the EU citizens or civil society.

How the EU Courts Engage with Science?

In our research – to be published soon in EU Environmental Principles and Scientific Uncertainty before National Courts – The Case of the Habitats Directive co-edited by Mariolina Eliantonio, Emma Lees, and Tiina Paloniitty and forthcoming with Hart Publishing – we examine the annulment and infringement cases (Article 263 and 258 TFEU) relating to the protection of the environment and public health completed by the EU Courts in five years, that of 2014-2018. We aimed to better understand how the EU Courts navigate between competing narratives and data in cases characterised by scientific uncertainty concerning the empirical facts, overcoming the absence of independent specialised expertise. We investigate how the EU Courts structure their engagement with science by interpreting the applicable legal frameworks and how they moderate the burden of proof with the precautionary principle. We also explore the constraints on their independent fact-finding within judicial proceedings – which is virtually non-existent – and the results of process-oriented review and polishing other administrative standards substituting for direct judicial engagement with science.

A Modest Toolbox

We found that the EU Courts’ toolbox to deal with the science underlying contested EU measures or infringement disputes remains limited. While the EU Courts apply the precautionary principle to bridge the gap between the law and intrinsically uncertain empirical appraisals, their scrutiny of the boundaries of EU institutions’ and bodies’ discretion in justifying their precautionary measures is restricted by their epistemic capacity. For instance, in GE Healthcare, the question was whether new evidence on the accumulation of the substance at issue in the brain without any clinical data on its persistence was sufficient to state a neurological risk. The applicant argued that three hundred million doses had been administered since 1988, and there were still no signs of clinical problems. In response, the EGC picked up several factors indicated by the competent scientific committee that might indirectly suggest the existence of risk, even though no direct evidence was available. Per the precautionary approach, the cumulative analysis of multiple indirect pieces of evidence was enough in the absence of direct evidence. Arguably, in similar cases, the assessment of indirect evidence or risk in lack of direct evidence may be subject in the future to reasonable disagreement before the EU Courts.

On the contrary, in TestBioTech, one of the arguments related to the use of glyphosate and pesticides with some GMOs. The Commission found some statistical evidence of unintended effects to be irrelevant. An environmental NGO challenged the Commission’s interpretation of the data considering that the underlying risk assessment of the European Food and Safety Authority had not been sufficiently precautionary and that, due to the degree of uncertainty, the case deserved further investigation. The EGC dismissed the plea, requiring the ‘evidence’ of a manifest error. However, this part of the dispute revolves around the kind of conclusions that should be reasonably drawn from the existing data, considering the precautionary principle rather than the completeness of evidence. Do the generalist EU judges possess adequate expertise to decide on the most plausible interpretation of scientific data?

There is always a risk that the Member States would try to take advantage of the Court of Justice’s epistemic limitations and avoid sanctions for EU law infringements. Sometimes, however, a case lends itself to a way out from the scientific conundrum, for instance, through sorting out the relevant and irrelevant factors under the applicable legislation. In a case against Italy, revolving around the alleged omission to remove plants infected by a specific bacterium, the question at stake concerned the determination of a ‘suitable’ moment to conduct inspections and detect the bacterium. The Commission claimed there was a specific period of the year for the inspections, while Italy claimed that the bacterium could spread throughout the whole year. The ECJ refrained from taking a position and focused on another related obligation imposed on the Member States by the relevant EU legislation. It stated that if inspections are conducted later in the year, they may identify the bacterium, but that point in time would be too late to remove the infected trees.

Scientific Uncertainty and Judicial Authority

These and more cases decided by the EU Courts raise questions about the consequences of the EU Courts’ limited engagement with science, generating risks for the accountability of EU institutions and effective enforcement of EU environmental law against the member States. A question also arises about the limits of the precautionary principle in bridging the gap between law and science while maintaining the ideal of the rule of law. The lack of direct and transparent engagement with science by the EU Courts, despite the growing docket of science-intensive cases, may also, in the long run, affect the authority of their decisions in the eyes of the Member States and private parties alike.

Posted by Mariolina Eliantonio (Maastricht) and Michał Krajewski (iCourts)

Suggested citation: M Eliantionio and M Krajewski, “Is the EU Courts’ toolbox to tackle scientific uncertainty sufficient?”, avaible at