The EU has introduced a Carbon Border Adjustment Mechanism (CBAM), which extends its carbon prices to imported products in some sectors. Increasingly considered by other countries, such border carbon adjustments (BCAs) are facing a global backlash against the lack of consideration of the adverse impacts on developing countries and particularly, least developed countries (LDCs). This article first argues that small overall import volumes support the conclusion that exempting or lessening BCA requirements from LDCs would not undermine developed countries' climate-related objectives in practical terms. An economic analysis of EU and UK trade in relation to a CBAM supports this assertion. However, legally, such an exemption or development-based preferential treatment is difficult under existing multilateral trade rules and jurisprudence, owing to the legal characterization and objectives of BCAs; their interaction with existing special and differential treatment (SDT) provisions; and complexity of available policy options. We thus highlight the gap between normative aims of SDT provisions to support development, and current WTO law and jurisprudence which expose WTO members providing preferential treatment to allegations of discrimination. With increasing unilateral climate action, an inability to integrate SDT more meaningfully into WTO non-discrimination frameworks risks further weakening of international cooperation on climate and trade.

This article examines a significant question in navigating trade and climate tension: how to recognize another country as having equivalent climate regulations. Such equivalence forms a core component of many proposed models of so-called climate clubs. Establishing equivalence between distinct national climate regulation regimes poses a unique challenge that draws upon both trade and environmental international cooperation. Drawing on existing proposals, I examine prospects for country-based cooperation through three models: ETS-linking, benchmarking of shared methods and minimum standards, and benchmarking of outcome duties. The analysis concludes that all models necessitate some trade-offs between the goals of rigorous oversight of climate objectives, inclusivity, and WTO compliance. Benchmarking of shared methods and minimum standards seems most feasible, and would provide a deeper level of integration between trade and climate cooperation, but necessitates a shift in how countries, particularly the EU, oversee regulatory compliance.

WTO rules prohibit Free Trade Areas (FTAs) that provide tariff-free access or services liberalization in only one or a few sectors. In this sense, a narrow, sectoral approach to concluding an FTA between the EU and the UK would contravene WTO law. However, assuming the EU and the UK were able to agree a substantially broad tariff-free FTA, WTO rules would not prevent them from moving further to maintain the bulk of the benefits of the Customs Union and the Single Market in a few key sectors. They could establish customs union-like conditions by coordinating external tariffs in some sectors and agreeing on relaxed Rules of Origin (RoOs) administered lightly and Single Market-like access could be approximated through sectoral Mutual Recognition Agreements. Such an approach would enable continued deep integration, whose desirability has been signalled on both sides. It would fall short of current market access levels even in the selected sectors, and, in the case of tariff coordination, re-create some of the limits to an independent trade policy that Brexit aimed to remove. If the trade-off were deemed desirable, however, the approach could be reconciled with WTO rules including the ‘Most Favoured Nation’ requirement that equal treatment be awarded to all WTO Member States.

When establishing whether a disputed regulation is protectionist under the WTO National Treatment Principle, there are two key elements: its effect on the market for competitive products, and its intent or policy rationale. Yet the Appellate Body has formally rejected both elements, and in the surprising 2014 outcome of EC–Seal Products, under the key provision GATT Article III(4), the latter was simply denied. This obfuscation leads to implicit and explicit conflation of these elements. In some disputes, qualitative findings about the existence and nature of competitive relationships are presented using the language of quantitative market analysis. In others, compelling policy objectives shape the outcome of a supposedly market-based analysis. This article proposes an approach that synthesizes two strands of scholarship, advocating more rigorous use of market-based evidence and stronger analysis of policy rationale. Separating these elements will achieve the appropriate balance between them and lead to greater transparency in dispute outcomes.

The WTO Secretariat describes sustainable development as a central WTO principle. Relevant international law treaties have declared sustainable development's mutual supportiveness with trade liberalization, and also emphasized the need to balance its ‘pillars’: economic development, often equated with trade liberalization, with environmental conservation and social welfare. While ‘mutual supportiveness’ suggests that sustainable development's environmental and social goals are a side effect of trade liberalization, ‘balancing’ involves weighing these different goals, and prompts the difficult question of which are most important, and who is empowered to decide. This paper traces these two broad theoretical conceptions through WTO legal texts, negotiations and dispute settlement, arguing that they have important pragmatic implications. In particular, to create mutual supportiveness WTO Director-General, Pascal Lamy, has stated the need for adequate domestic policies, suggesting that the WTO should support these. Yet, if they have negative trade impacts, pure ‘sustainable development’ policies may be difficult to balance against the WTO obligation to liberalize trade.

Should consumers' preference for ‘green’ products help justify, from a WTO perspective, emerging regulations such as restrictions on trade in non-sustainable biofuels? Despite the role consumer preferences have played in WTO disputes, in association with the ‘like’ products concept, there has not been enough focused examination of their specific influence, particularly in disputes on ethical public policy issues, such as environmental or health regulations. To this end, this paper examines key GATT Article III disputes, pointing out that they included attempts both to measure, and also to interpret, consumer preferences. The latter approach becomes more tempting when consumer preferences are difficult to measure; import bans or restrictions associated with ethical public policy regulations can bring about such a situation. A hypothetical dispute about EC biofuels sustainability criteria demonstrates this problem. Options to make the concept of consumer preferences more coherent include limitations on how they can be invoked, and an increased commitment to capturing them through measurement.