Flag State jurisdiction

Definition
 {| class="wikitable mw-collapsible" style="background-color:#ffffcc;" ! scope="col" style="background-color:#ffffaa;"| Flag State jurisdiction Pursuant to the law of the sea, a ship has the nationality of the State whose flag it is entitled to fly. In turn, that State has the exclusive jurisdiction over the ship in question while the ship is on the high seas. Conversely, other States are prohibited from exercising enforcement jurisdiction over a vessel that does not fly their flag.

This principle of the exclusive jurisdiction of the flag State is a corollary of the rights enjoyed by vessels on the high seas – notably the freedom of navigation – as it serves to prevent interference by other States on the high seas. However, the principle is subject to specific exceptions which enable third States to exercise enforcement jurisdiction over vessels that do not fly their flag.

One exception is provided by Article 110 of the Law of the Sea Convention, which grants a ‘right of visit’ to States that are not the vessel’s flag State. Under the right of visit, a State may send a designated vessel to visit and inspect a foreign private vessel. The exercise of this right is dependent on there being “reasonable ground for suspecting” that the vessel is engaged in piracy, slavery, or unauthorised broadcasting, or that the vessel is either without nationality or, in reality, of the same nationality as the inspecting State. Whether the right of visit may be carried out using cyber means is unclear and disputed.

However, the Law of the Sea Convention does not represent the totality of the legitimate exceptions to flag State jurisdiction. The ability to exercise enforcement jurisdiction over foreign vessels may also be provided for in other international treaties. Moreover, the United Nations Security Council, acting under Chapter VII of the UN Charter, may pass resolutions that compel member States to engage in enforcement actions at sea, usually with the flag State’s consent. Very few resolutions have required States to exercise their enforcement jurisdiction over foreign vessels without the flag-State’s consent.