To avoid penalizing exporters that already paid carbon prices, the EU Carbon Border Adjustment Mechanism credits carbon taxes and Emissions Trading Schemes in third countries. By excluding instruments of traditional regulation (e.g. emission standards) and indirect carbon prices (e.g. fuel excise taxes) from this crediting mechanism, the EU is criticized for discriminating against countries that do not follow its climate model, in breach of international trade and climate law. This article seeks to nuance this criticism by arguing that the calculation of actual emissions (instead of default values) under the EU CBAM allows exporters to reflect compliance with foreign emission standards, and thus respects states' right to pursue emission reductions through traditional regulation. However, amendments of the CBAM Regulation are necessary to recognize the positive and negative impact of indirect carbon prices on decarbonization, and the role of carbon-crediting mechanisms in equalizing carbon costs in a more flexible and equitable way.

With its narrow focus on price-based policies and ‘explicit’ carbon prices, the EU carbon border adjustment mechanism (CBAM) aims to prevent carbon leakage by ensuring that imported products ‘bear’ the same exact economic costs ‘borne’ by EU products. The proposed US border carbon adjustment (BCA) and the recent proposal for a global steel and aluminium arrangement (GSAA), by contrast, reflect a broader focus on environmental equivalence and recourse to punitive or quasi-punitive remedies. All recently proposed carbon border measures suffer from specific limitations. Further, albeit to a different extent, they are all associated with problematic aspects in terms of WTO law compatibility. This research note enquires whether the GSAA could be fine-tuned at the regulatory design stage in such a way as to provide an environmentally effective and WTO law compatible way forward. The analysis illustrates that recourse to an installation-based approach, emission limit values and product standards would achieve these goals. Nonetheless, the implementation of this ambitious strategy would be fraught with political obstacles.