International Protection of Foreign Investments in Offshore Energy Production and Marine Environmental Protection: Birds of a Feather or Frenemies Forever?

Initially, international investment law and international law on the protection of the marine environment were two branches that developed separately. As these international regimes mature, they often speak to the same facts, bringing about their ever-increasing normative interaction, way before any disputes arise. The regulation of investments in offshore energy production is chosen as a case study because it exemplifies how these two bodies of international law can interact. The article does not conceptualize these two international regimes as inherently antagonistic but instead highlights their potential complementarity. Yet, it is primarily the issue of normative conflicts between those two regimes which has generated heated scholarly debates. Against the backdrop of sweeping critiques about the potential ‘regulatory chill’ of international investment agreements and their investor-State dispute settlement mechanism, this contribution examines whether arbitral tribunals have interpreted and applied investment rules in a fashion that can unduly restrict the discretion of host States to honour their marine environmental obligations. First, it explores why and how international investment law and marine environmental law interact and influence each other’s implementation. In a second step, the article investigates the impact (if any) of investment obligations on the discretion of host States to comply with their marine environmental protection obligations. Adopting a forward-looking perspective, it finally enquires into the potential impact of the reformed provisions under new generation IIAs on the right and duty of States to take all necessary measures to protect the marine environment against pollution from offshore energy production activities