Transnational Climate Due Diligence (CDD): Existence, limitations and potentialities in international and comparative law

Please join us for a lecture by Dr Paul Mougeolle. He recently completed his PhD at Paris Nanterre University and Potsdam University, researching the usefulness of the due diligence concept in the fight against climate change in international and comparative law. His PhD journey included various contributions to litigation, particularly through his affiliation with Notre affaire à Tous (NAAT). Notably, he helped initiate the climate cases against TotalEnergies, BNP Paribas, and the French State. He recently established a partnership with the German-based NGO Green Legal Impact to reinforce the exchange of ideas in this field between France and Germany.

Abstract

This PhD thesis explores the existence and boundaries of “climate due diligence” (CDD) owed by States and corporations in international law, human rights law and domestic law in selected Global North jurisdictions. It finds that due diligence applies to climate change, since prevention remains possible at the individual level, despite the cumulative nature of global warming. CDD is also enforceable: courts recognise climate-related impacts as injuries and establish causation through the concept of shared responsibility. The redressability of CDD claims depends, however, on the existence of either specific legislation or scientific and institutional consensus. Absent such conditions, States and corporations must benefit from wider discretion while implementing best efforts. A historical analysis of compliance with CDD reveals past and ongoing breaches by public and private Global North actors, which may give rise to secondary obligations, such as compensation or enhanced mitigation. This thesis concludes that CDD has emerged as a transnational legal norm with growing recognition across jurisdictions, and that it provides a meaningful tool to advance climate accountability.