The Exclusive Jurisdiction of Flag States: A Limitation on Pro-active Port States?

The loosely phrased, and undefined, ‘exclusive flag state jurisdiction’ principle of the United Nations Law of the Sea Convention Article 92, has arguably proved to be a red herring for states and academia, in its being raised as a limiting factor to extra-territorial prescription by non-flag states. This has extended to port state jurisdiction discussions, and was raised by analogy for aircraft, before the European Court of Justice, in relation to the limits of jurisdiction over high seas overflight. This paper argues for a limited scope to the term ‘jurisdiction’ in Article 92. It concludes that far from being a limiting factor, the principle of flag state exclusivity is solely concerned with the enforcement jurisdiction of states on the high seas. The increasing use of port state prescriptive jurisdiction, particularly those practices with extra-territorial effect, provides further evidence that this is the correct interpretation.