Caroline E. Foster in her recent book looks at the widely studied issue of the standard of judicial review in international adjudication and sees (and shows to the reader) something entirely different.Footnote ¹ Her new perspective reveals thus far hidden dynamics and offers useful analytical insights into the evolving relationship between sovereign states and international courts in the context of scrutinizing national environmental and health related measures.

The book offers an alternative approach to studying the phenomenon that is normally labelled as ‘standard of review’ by international courts and tribunals. Moving away from gauging whether international fora adopt deferential or intrusive standards in their reviews, more recent works have already been digging deeper into the different modes, functions and overall context of deference that shape the interface between international courts and sovereign states.Footnote ² In her book, Caroline Foster goes even further and proposes that we should be looking at this issue from an entirely different perspective. Instead of examining the outcome of the alleged judicial review (a terminology that she contests, as seen below) or the aims, contexts, and modes of adopting certain standards of review, one should be focusing on the touchstones that international courts use in their adjudicatory processes.

Her study looks at and dissects the argumentative standards that international courts use as requirements that are embedded in international environmental or health related obligations, namely, regulatory coherence, due regard, and due diligence. In order for states to be able to defend their regulatory measures before international courts, they will have to demonstrably meet such standards, which makes Caroline Foster’s inquiry not only theoretically enriching, but also highly relevant from the pragmatic point of view of regulatory and litigious actors. Bringing out such global regulatory standards as shared elements in the assessment of various international fora not only provides new angles for scholarly analysis but may also encourage cross-jurisdictional borrowing between international courts and tribunals.

A sustained gaze at such judicial argumentative tools reveals the deterministic forces that shape the depth, merits, impacts, and long-term consequences of international adjudicatory decisions for the possibilities of various actors, and for the legitimacy of international law more broadly. Professor Foster calls these benchmarks as ‘global regulatory standards’, which emerge from the regulatory activities of sovereign states regarding environmental and health related matters under various specialized regimes of international law. These standards are necessarily more vague than legal rules and emerge from such rules through judicial interpretation.Footnote ³ Standards are also distinct from principles, which may, however, inform the way in which standards are defined.

Professor Foster also challenges the long-standing scholarly tradition of distinguishing the ‘methods’ or ‘standards’ of review as being something distinct from the underlying international law rules themselves that international courts and tribunals interpret in their judgments. She argues that calling such practice as ‘judicial review’ misses the pointFootnote ⁴ and projects an inaccurate and altogether misleading picture on the lived realities of international adjudication and, more fundamentally, on the relationship between sovereign states and international courts. Instead, she proposes using the terminology of adjudication, which shifts the analytic focus to balancing of courts, which captures the essence of the dynamics that unfold before international fora when they interact with domestic measures. In her view, ‘judicial review’ and ‘standards of review’ are not necessary concepts to understand and explain the process of international courts’ deferential interaction with regulatory decisions, studying the content and contours of global regulatory standards is sufficient in this respect.

The book first traces the genesis of such global regulatory standards. Their emergence is seen as a necessary corollary of the increasing number of disputes where courts are asked to appraise the adequacy and lawfulness of domestic measures, which triggers the need for the judicial articulation of the contents of such obligations, which courts meet through the elaboration of global regulatory standards. Global regulatory standards are emanating from binding obligations that states have already assumed under international law, however, the precise content of such standards can only be revealed in a legal dispute through authentic judicial interpretation.

From this analytical vantage point, the book examines the origins, nature, effect, and overall benefit of global regulatory standards. By opening up the interpretative practices of international fora in environmental and public health related disputes, the empirical chapters extract three overarching global regulatory standards that international courts use across jurisdictions and substantive legal contexts. The first standard is ‘regulatory coherence’Footnote ⁵ between domestic measures and their legitimate objectives, which has a range of forms, such as (i) capability review, i.e., reviewing whether regulatory measures are capable of achieving their stated objectives, (ii) necessity testing, which is present as an express legal requirement under several specialized regimes of international law, (iii) reasonableness assessment, which has been applied by various cases by the International Court of Justice (ICJ), inter-state arbitral tribunals, and even investment arbitral tribunals. Furthermore, the regulatory coherence review can also take the form of focusing on (iv) rational relationships between state measures and their objectives, which is a central requirement in WTO law, and on (v) a strict sense proportionality, which occurs in cases when international courts weigh the relative merits of the legal interests sought to be protected by domestic regulatory judgments.

The second main regulatory standard is that of ‘due regard’, that is, an obligation for states to consider the effects of their actions on individuals of other states.Footnote ⁶ This formula is explicitly provided under the UN Convention on the Law of the Sea (UNCLOS), but the book also traces the due regard standard in a range of other international legal contexts, such as WTO law and investment treaty arbitration. The third regulatory standard is that of due diligence in the prevention of harm.

The theoretical framework is deeply rooted in an extensive empirical analysis, which pays due regard to the lived realities and inner workings of international judicial dispute settlement. This is reflected also in the book’s methodology, as its arguments are enriched by insights gained through interviews with various international judges, counsels, and legal practitioners involved in settling legal disputes before various international judicial fora. The author’s familiarity with and focus on the practice of international adjudication shines through also from the analytical findings, which trace the origins of relevant global regulatory standards, such as the pleadings of the parties or argumentative practices of the bench, instead of focusing on a mere textual assessment of the judgments themselves. The inquiry also stresses the importance of different interpretive practices and types of judicial logic in the formulation of standards, while acknowledging the formative role of judicial pragmatism, instinct, common sense, and intuitive reasoning.Footnote ⁷ The special role and importance of better understanding the role of different epistemic rationalities in the judicial assessment is shared by others as well,Footnote ⁸ especially in scientific disputes to which environmental and health related regulatory disputes belong.

Overall, the book paints a three-dimensional picture of what it calls ‘standards-enriched international law’,Footnote ⁹ by studying the third-party impacts of the operation of global regulatory standards on the status of private actors in international law, and the more systemic implications of such argumentative practices for the legitimacy of international law, and for the contours of sovereign regulatory choices in the context of international adjudication.

As to its structure, having introduced the key conceptual framework in Part I, the book provides a detailed analysis on the judicial practice of several international courts and tribunals in relation to each of the three relevant regulatory standards. Part II is devoted to examining the standards of regulatory coherence, due regard, and that of due diligence in the case-law of the ICJ, the dispute settlement mechanisms of UNCLOS, and the practice of the Permanent Court of Arbitration. Further chapters examine how the standards of necessity and rational relationship reviews are used by the practice of WTO dispute settlement procedure (Part III) and those of regulatory coherence and proportionality in investment arbitral tribunal awards (Part IV). These empirical parts provide a meticulous analysis of almost 170 international adjudicatory decisions, unpacking how different regulatory standards play out in the adjudicatory assessment. Part V weaves the threads together from the case-law analysis and discusses three overarching critical questions and systemic challenges in two separate chapters.

The overarching goal of the book lies in answering three wider questions. First, how effective is the application of global regulatory standards in buttressing the legitimacy of international law in the eyes of sovereign states? Second, how appropriate it is to entrust the formulation of such global regulatory standards with international courts? Third, how to handle the challenges and opportunities that arise in the process of emergence of such global regulatory standards?

As to the first issue, the book emphasizes that ‘standards-enriched’ international law helps buttressing international law’s claim to legitimacy in the eyes of sovereign states by reinforcing domestic commitments. However, accommodating states’ own commitments under global regulatory standards comes at the price of capping international law’s ability to better cater for global substantive needs.Footnote ¹⁰ Replacing the conceptual lenses of ‘judicial review’ with those of judicial balancing between different interests begs the question whose interests and needs international courts are (and should be) considering in their balancing decisions. In principle, global regulatory standards, by their very nature, would be capable of allowing courts to look beyond the strict confines of the inter partes adjudicatory process, as they embody a balance struck between the interests of whole range of actors subject to the given international law rules from which they emanate. However, the book also warns that some real-life constraints and limitations, inherent in how these standards are articulated, suggest that international courts and tribunals may not be used as vehicles to compel states to enforce protection of certain global values. Caroline Foster argues, for instance, that allowing international courts to conduct a strict proportionality analysis would be too demanding towards sovereign decision-makers, and therefore, she sees greater value in using due regard standards in lieu of proportionality testing.Footnote ¹¹

As to the second question as to the appropriateness of entrusting international courts with defining global regulatory standards, the overarching message of the book is that scholars and states should pay more attention to the ways in which such standards are created. Importantly, such a process may not be entirely entrusted to international courts due to some social and formal constraints in the international adjudicatory process.

As to the final issue of structural challenges, the book investigates three problems, namely, how global standards interact with the fragmentation of international law, how they influence the role of private actors in international adjudication, and how standards-enriched international law affects the contours of sovereignty.Footnote ¹² The analysis points out that certain regulatory standards seem to vest private actors with substantive entitlements under certain fields of international law, such as investment protection, whereas under other contexts, such as environmental legal obligations, regulatory standards appear to be underutilized in announcing relevant obligations for corporations.

Concerning fragmentation, standards-enriched international law carries the potentiality of a greater integration of international law. As to sovereignty, measuring domestic regulatory decisions against the touchstone of global regulatory standards, sovereign decision-making comes to be seen in the light of having conferred powers, which will open the floor for adjudication. While this logic may seem familiar to administrative lawyers, Caroline Foster cautions against overstating any similarity between administrative judicial review of domestic measures and the realities of the extent to which international courts can assess the legality of sovereign policy measures.Footnote ¹³ Finally, as an important structural implication, the book sees the ultimate consequence of standards-enriched international law in the taming of sovereignty. In a finding with potentially far-reaching implications, the author discerns a trend in which courts increasingly compel states to pay due regard to the populations of other states, and that the contours of sovereignty should change considering the increasing interdependencies between human populations.Footnote ¹⁴

Professor Foster’s thought-provoking and insightful book theorizes the practical realities of international adjudication, which will be of interest to scholars as well as practitioners working in areas of trade law, law of the sea, environmental law, health law, and even beyond, given that such questions are coming to the forefront of international adjudication in a number of new settings where global regulatory standards will be needed to decide new types of international disputes. The book is a highly recommended reading to anyone who would like to better understand what and why one can (or cannot realistically) hope to receive from international courts and tribunals in seeking regulatory answers that are more attentive to global considerations in tackling the planetary challenges of the twenty-first century, including pandemics, the digital revolution, and the climate crisis.