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Flag State Jurisdiction

Flag State Jurisdiction

I have received many inquiries regarding Flag State Jurisdiction. This seems to be a topic of interest for merchant mariners as well as yachting professionals. The question has been “where is the legal reference for why a flag state has jurisdiction over the vessel regardless of where it is physically located in the world?”

As this is very pertinent and quite interesting, I wanted to take the time to answer this question from an international and a national perspective.

International – United Nations perspective:
In 1982 the International Law of the Sea Convention was signed by many countries around the world. It states the following (excerpts of Articles 91, 92 & 94). I recommend that if you are interested in reading the convention in its entirety, download it from the internet at the following link:

Article 91 Nationality of Ships
1. Every State shall fix the conditions for the grant of its nationality to ships, for the registration of ships in its territory, and for the right to fly its flag. Ships have the nationality of the State whose flag they are entitled to fly. There must exist a genuine link between the State and the ship.

2. Every State shall issue to ships to which it has granted the right to fly its flag documents to that effect.

Article 92 Status of Ships
1. Ships shall sail under the flag of one State only and, save in exceptional cases expressly provided for in international treaties or in this Convention, shall be subject to its exclusive jurisdiction on the high seas. A ship may not change its flag during a voyage or while in a port of call, save in the case of a real transfer of ownership or change of registry.

2. A ship which sails under the flags of two or more States, using them according to convenience, may not claim any of the nationalities in question with respect to any other State, and may be assimilated to a ship without nationality.

Article 94 Duties of the Flag State
1. Every State shall effectively exercise its jurisdiction and control in administrative, technical and social matters over ships flying its flag.

2. In particular every State shall: (a) maintain a register of ships containing the names and particulars of ships flying its flag, except those which are excluded from generally accepted international regulations on account of their small size; and (b) assume jurisdiction under its internal law over each ship flying its flag and its master, officers and crew in respect of administrative, technical and social matters concerning the ship.

3. Every State shall take such measures for ships flying its flag as are necessary to ensure safety at sea with regard, inter alia, to: (a) the construction, equipment and seaworthiness of ships; (b) the manning of ships, labour conditions and the training of crews, taking into account the applicable international instruments; (c) the use of signals, the maintenance of communications and the prevention of collisions.

4. Such measures shall include those necessary to ensure:
(a) that each ship, before registration and thereafter at appropriate intervals, is surveyed by a qualified surveyor of ships, and has on board such charts, nautical publications and navigational equipment and instruments as are appropriate for the safe navigation of the ship;
(b) that each ship is in the charge of a master and officers who possess appropriate qualifications, in particular in seamanship, navigation, communications and marine engineering, and that the crew is appropriate in qualification and numbers for the type, size, machinery and equipment of the ship;
(c) that the master, officers and, to the extent appropriate, the crew are fully conversant with and required to observe the applicable international regulations concerning the safety of life at sea, the prevention of collisions, the prevention, reduction and control of marine pollution, and the maintenance of communications by radio.

5. In taking the measures called for in paragraphs 3 and 4 each State is required to conform to generally accepted international regulations, procedures and practices and to take any steps which may be necessary to secure their observance.

6. A State which has clear grounds to believe that proper jurisdiction and control with respect to a ship have not been exercised may report the facts to the flag State. Upon receiving such a report, the flag State shall investigate the matter and, if appropriate, take any action necessary to remedy the situation.

7. Each State shall cause an inquiry to be held by or before a suitably qualified person or persons into every marine casualty or incident of navigation on the high seas involving a ship flying its flag and causing loss of life or serious injury to nationals of another State or serious damage to ships or installations of another State or to the marine environment. The flag State and the other State shall cooperate in the conduct of any inquiry held by that other State into any such marine casualty or incident of navigation.

National – United States perspective:
Title 18 USC – Crimes & Criminal Procedures Subpart 7 Special Maritime and Territorial Jurisdiction of The United States defined:

(1) The high seas, any other waters within the admiralty and maritime jurisdiction of the United States and out of the jurisdiction of any particular State, and any vessel belonging in whole or in part to the United States or any citizen thereof, or to any corporation created by or under the laws of the United States, or of any State, Territory, District, or possession thereof, when such vessel is within the admiralty and maritime jurisdiction of the United States and out of the jurisdiction of any particular State.

I found this information very interesting and I think it answers the question of why a flag state has jurisdiction over the vessel no matter where in the world it is located.

Contact me if you have any questions of any of the above requirements or any other licensing/or mariner credentialing issue at my email below.

Amy Morley-Beavers serves as the VP Regulatory Compliance/Academic Principal at MPT in Fort Lauderdale as well as Vice Chairman of the Merchant Personnel Advisory Committee (MERPAC) appointed by the Secretary of Homeland Security as well as the Vice President of the Maritime Education Standards Counsel (MESC). She holds a Masters License and has been advising mariners on matters related to training, licensing and certification since 1986. You can send your questions or comments at