“Nationals” at Forty: From an Undefined UNCLOS Term to Due Diligence Obligations on the State of Nationality to Combat IUU Fishing

Illegal, unreported and unregulated (IUU) fishing represents a global common concern, incorporating large-scale and highly mobile environmental, economic, and sometimes criminal, concerns. IUU fishing can result in dysfunctional fisheries governance, including through the non-application of relevant conservation and management measures. Non-application results, in part, from both incomplete implementation and insufficient enforcement by flag, coastal, port, and market States, and the States of nationality. This article focuses on the State of nationality that may exercise territorial and extraterritorial prescriptive jurisdiction on the basis of the active personality principle of jurisdiction. Firstly, global instruments have long held the State of nationality as a complementary means of eliminating IUU fishing, but State practice has been previously limited. The obligations of the State of nationality have been increasingly emphasized in successive instruments as well as the treaty interpretations provided by international organizations and international courts and tribunals. Secondly, regional fisheries management organizations and arrangements have matched these global developments by equally expanding their active personality-based practice concerning IUU fishing. Thirdly, States have been implementing their obligations to exercise active personality-based jurisdiction by prescribing and enforcing domestic laws. By bringing the State of nationality to the forefront this article will demonstrate the increasing relevance of this jurisdictional actor to protect the global commons from common threats, despite its often-overlooked status in fisheries literature.