法学研究 94 巻 1 号（2021：1）

1）

Legal Status of Sunken State Vessels

OYAMA, KaèIntroduction
1. Sunken State Vessels in General International Law
1.1 Definition of Warships in UNCLOS
1.2 Sovereign Immunity
1.3 International Conventions and State Practices
2. The Treatment of Sunken State Vessels in the UCH Convention
2.1 Drafting Process
2.2 Definition of “State Vessels and Aircraft” and General Principle
2.3 Control Mechanisms in Each Maritime Zone
Conclusion

Introduction
The entry into force in 2009 of the UNESCO Convention on the Protectionof Underwater Cultural Heritage (hereinafter referred to as “the UCH
2）Convention”)

adopted in 2001 could be regarded as a welcome development toelaborate or clarify any ambiguity of only two general provisions as Article 149
and 303 with regard to the protection of underwater cultural heritage in United
Nations Convention on the Law of the Sea in 1982 (hereinafter referred to as
3）“UNCLOS”) . Some texts of the UCH Convention, however, give controversy in1） This article primarily follows to the terminology of the UCH Convention which uses
“state vessels” in Article 1(8).
2） Convention on the Protection of Underwater Cultural Heritage (with annex), Paris, 2
November 2001, vol.2562 (Part I), United Nations Treaty Series (2009) pp.3―135.
3） United Nations Convention on the Law of the Sea (with annexes, final act andprocès-verbaux of ratification of the final act dated 3 March 1986 and 26 July 1993), Concluded at Montego Bay on 10 Decernber 1982, vol.1833, United Nations Treaty Series(1994) pp.3―581.
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fact to the comprehensive international order of the seas in relation to the otherprovisions of UNCLOS and general rules of international law.
The treatment of sunken state vessels is also one of the most controversial
and challenging issues which the drafters of the UCH Convention faced.
International law in relation to warships is complex, uncertain, and politicallyhighly sensitive. The key provisions of the UCH Convention regarding thisissue, the legal status of sunken State vessels, are Article 2(8), 7(3), and 10(7)and it is one of the main reasons why most of maritime States hesitate to ratify
4）

the Convention .

This article will focus on the reason and background of such controversy.
First, it examines the existing international law and related State practices inorder to evaluate the legal status of sunken State vessels under customaryinternational law. Second, it reviews mainly Article 2(8), 7(3), and 10(7) of the
UCH Convention. The purpose of this article is to clarify the gap between the
UCH Convention and customary international law in relation to the legal statusof sunken State vessels and, thereafter, try to explore a key to resolve the gap.

1. Sunken State Vessels in General International Law
1.1

Definition of Warships in UNCLOS
According to Article 29 in UNCLOS, “warship” means “a ship belonging to

the armed forces of a State bearing the external marks distinguishing such shipsof its nationality, under the command of an officer duly commissioned by thegovernment of the State and whose name appears in the appropriate service listor its equivalent, and manned by a crew which is under regular armed forcesdiscipline”.
Warships had enjoyed specific right for centuries under customaryinternational law and it codified in Article 95 that they “have complete immunityfrom the jurisdiction of any State other than the flag State” on the high seas.
Also Article 96 provides that “[s]hips owned or operated by a State and used
only on government non-commercial service shall, on the high seas, have4） France ratified the Convention in 2013.
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complete immunity from the jurisdiction of any State other than the flag State”.
This principle also extends in Article 58(2) to the vessels which navigate in
the EEZ of coastal States “in so far as they are not incompatible” with theprovisions relating to the EEZ set out in Part V of UNCLOS. Also in Article 32
5）which provides as below, the rules of innocent passage

are respected in the

territorial sea of the coastal states:
With such exceptions as are contained in subsection A and in articles 30
and 31, nothing in this Convention affects the immunities of warships andother government ships operated for non-commercial purposes.
1.2

Sovereign Immunity
While the immunity of foreign States was absolute (absolute doctrine) until

early nineteenth century, a restrictive view gradually took place (restrictive
doctrine) towards the end of the nineteenth century. An exception was envisaged

for acts performed jure gestionis or jure privatorum that is, performed by a6）

foreign State in a private capacity as a legal person subject to private law .

In the line with the restrictive doctrine, whereby immunity is confined tocircumstances in which a State acts as a State, immunity extends only to State
craft that are engaged in non-commercial service. Government-owned ships
operated for commercial purposes are subject to the same treatment as privately
7）

owned merchant ships .

The question is that whether or not the principle of sovereign immunity
continues to apply to a State vessel even after it has sunk. There are two streams;
first, immunity does not apply after a warship sunk on ground of that a warshipis not a warship any longer once it sunk, and a ship is not a ship any longer.
Sunken vessel is not the object which can meet the definition of vessel. With
regard to warships particularly, as Article 29 provides a ship must be “under5） See L. Migliorino, “The Recovery of Sunken Warships in International Law”, in B. Vukas ed., Essays on the Law of the Sea (1985) p.250.
6） A. Cassese, International Law (2005) p.100.
7） S. Dromgoole, Underwater Cultural Heritage and International Law, p.137.
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command” and “manned” and the conditions which are only possible while it is8）

operational . Sunken warships are not the objects to meet the definition ofwarship. As such, they are not subject to flag State jurisdiction any longer andtherefore not retain their immunity any longer. This position leads to theconclusion that the flag State, qua flag State, cannot prohibit a salvage
attempted by another State or private operator.
Second position is more promising that sunken State vessel retains
immunity because the argument for immunity is on the fact that such craft arestate property. States have reasons for maintaining an interest in State vessels
after their sinking and these interests are not confined merely to casualties.
There are therefore legitimate basis for affording such property indefinite
9）

immunity .

A number of maritime States defend the second position and, according to
general rules of international law, the title of the sunken warships may be only
lost or transferred by: express abandonment; or capture or surrender under the10）

law of war
1.3.

International Conventions and State Practices
International legislation and State practices show that the legal status

implies that sunken State vessels, such as warships and vessels on government
service, regardless of location or of the time elapsed since their wreckage,remain the property of the State owning them at the time of their sinking, unless
it explicitly and formally abandon its ownership. Such sunken vessels should be
respected as maritime graves or reservoir of classified information of the flag
State. Thus, it is applied sovereign immunity to sunken State vessels and they
11）

shall not be salvaged without the express consent of the flag State.

8） See L. Caflisch, “Submarine Antiquities and the International Law of the Sea”, Netherlands Yearbook of International Law, vol.13 (1982) p.22; A. Strati, The Protection of theUnderwater Cultural Heritage (1995) p.235.
9） See A. Rubin, “Sunken Soviet Submarines and Central Intelligence: Law of Property
and the Agency”, American Journal of International Law, vol.69 (1975) pp.855―8.
10） See S. Yamamoto, “Chinbotsu Gaikoku-sen no Hikiage to sono Shoyu-ken” (Salvageof Sunken Foreign Vessel and the Ownership), Hogaku Kyoushitsu, vol.1, no.4 (1981) p.61.
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This position is confirmed by several international instruments, e.g., Article
14 of 1910 Convention for the Unification of Certain Rules with Respect toAssistance and Salvage at Sea
Convention on Salvage

12）, Article 4 (1) of the 1989 International

13）, 2007 International Convention on the Removal of

14）

Wrecks. There are also some representative cases where State have recognized

the sovereign immunity and title of sunken State vessels; the Exchange of Note
Constituting an Agreement between UK and Italy Regarding the Salvage of
HMS Spartan in 1952

15）

; Italy recognized the British title to the wreck;

Australia recognized the Dutch title to the Old Dutch Shipwrecks belonging to
the Dutch East India Company, covered by 1972 Agreement16）; France

17）

recognized US title to the CSS Alabama in 1989
title with La Belle; US recognized the French18）

in 2003.

There are remarkable cases in the US, the Juno and La Galga case in 2000
and the Mercedes case in 2011. It should be noted that after these cases, someparticularly concerned States, including US, Germany, Japan, Russia, Spain,
UK, clarified their position in their unilateral declaration on the legal status ofsunken State vessels by stating that sunken State vessels continue to enjoy
19）

sovereign immunity after sinking, wherever they are located.

1.3.1 The Juno and La Galga Case
In 1990s, a commercial salvage company, the Sea Hunt Inc., submitted anin rem claim respectively against two Spanish frigates, La Galga de Andalucia
20）

and the Juno, which were sunk in 1750 and 1802 in the US contiguous zone.

11） See M.J. Aznar-Gómez, “Legal Status of Sunken Warships ʻRevisedʼ”, Spanish Yearbook of International Law, vol.9 (2003) p.61.
12） Adopted on 23 September 1910, US Treaty Series, p.576.
13） Adopted on 28 April 1989, UN Treaty Series, vol. 1953, p.165
14） Adopted on 23 May 2007, IMO Doc. LEG/CONF.16/19 (2007).
15） Concluded on 6 November 1952, UN Treaty Series, vol. 158, p.432.
16） Concluded on 6 November 1972, Australian Treaty Series, no.18 (1972).
17） Concluded on 3 October 1989, UN Law of the sea Bulletin, vol. 20 (1996) p.26.
18） Signé à le 31 mars 2003, Journal officiel de la République française, nº144, p.10560.
19） These unilateral declarations can be found in Federal Register, vol.69, no.24 (2004)
pp.5647―8.
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The Sea Hunt Inc. was issued with a permit by the State of Virginia to search
for the wrecks and, when they were found, Virginia claimed title to them underthe Abandoned Shipwreck Act of 1987 (ASA). When Spanish government foundthat a permit for commercial exploitation had been awarded, it issued adiplomatic note of protest and expressed its wish to protect the sanctity of its
maritime gravesites. Despite the protest, intervention at the site went ahead and
Sea Hunt Inc. initiated an in rem salvage action in the District Court in Norfolk.
Although the District Court partially supported the Sea Hunt Inc.

21）

, the Courtof Appeal of the 4th Circuit fully supported Spanish claims to the two
wrecks22）. The US Supreme Court then finally confirmed this legal position in

23）

.

2001

The salvor insisted that the vessels had been abandoned by their owner andthat it was entitled to recover artefacts by the permit issued by the state of
Virginia. It concluded that the vessel had not been expressly abandoned by
Spain, by reversing a finding of the District Court that Spain had expressly
abandoned La Galga when it entered into the 1763 Definitive Treaty of Peacebetween France, Great Britain and Spain. Spain had transferred most of its
New World territories to Great Britain in the Treaty. Court of Appeal noted thatthe terms of the treaty did not provide the “clear and convincing evidence” ofexpress abandonment that was required, because of the absence of specificreference to vessels or shipwrecks in the Treaty. It continued that “[i]t is the right24）of the owner of any vessel to refuse unwanted salvage”.

This case shows some essential points; first, it gave the opportunity to
several States to explicitly state their position regarding the legal status of20） See L. Vierucci, “Le statut juridique des navires de guerre ayant coulé dans des eauxétrangères: le cas des frégates espagnoles Juno et La Galga retrouvées au large des côtesdes Etats-Unis”, Revue générale de droit international public, tome 105 (2001) p.705.
21） Sea Hunt Inc. v. Unidentified Shipwrecked Vessel or Vessels, 47 F. Supp. 2d 678 (E.D.
Va. 1999).
22） Sea Hunt Inc. v. Unidentified Shipwrecked Vessel or Vessels, 221 F.3d 634 (4th Cir.
2000).
23） Sea Hunt Inc. v. Unidentified Shipwrecked Vessel or Vessels, 221 F.3d 634 (4th Cir.
2000), cert. denied, 148 L.Ed. 2d 956, 121 C. Ct. 1079 (2001).
24） Sea Hunt Inc. case, 221 F.3d, op.cit., pp.640―1.
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sunken State vessels including warships. It was confirmed in US Presidential
Statement in 2001 that “title to foreign sunken State craft may be transferred or
25）

abandoned only in accordance with the law of the foreign flag State” and US“recognizes that title to a United States or Foreign sunken State craft, wherever
located, is not extinguished by passage of time, regardless of when such sunken
State craft was lost at sea”.
Second, the Court of Appeals held that sovereign vessels must be treateddifferently from privately owned ones. The so-called “implied abandonment
standard” would seem therefore to be least defensible where a nation has stepped
26）

forward to assert ownership of its sovereign shipwrecks.

Third, unauthorized salvage of sunken State vessels is legally precluded, thesalvor is denied any kind of reward, and artifacts removed from the bottom of27）

the sea must be returned to the sovereign owner.

1.3.2 The Mercedes Case
Odyssey Marine Exploration (OME) in the US discovered a shipwreck ininternational waters about 100miles west of the Straits of Gibraltar in 2007. A
number of coins and small artefacts were recovered from the site and flown into
the jurisdiction of the US District Court of Tampa, Florida, by OME

28）. Spainasserted; (a) the vessel was the Nuestra Señora de las Mercedes, a frigate of warof the Royal Spanish Navy that had exploded with great loss of life in 1804; (b)Spain had not abandoned its sovereign rights over the vessel; (c) underinternational and domestic US law, foreign State vessels should be afforded thesame legal regime as those of the US; (d) the court lacked subject-matter
jurisdiction over the res under the Foreign Sovereign Immunity Act of 1976
(FSIA).

25） Expressed on 19 January 2001, Federal Register, vol.69, no.24 (2004) p.5648.
26） Sea Hunt Inc. case, 221 F.3d, op.cit., p.647.
27） M.J. Aznar-Gómez, Treasure Hunters, Sunken State Vessels and the 2001 UNESCO
Convention on the Protection of Underwater Cultural Heritage”, The International Journal of Marine and Coastal Law, vol.25 (2010) p.213.
28） Odyssey Marine Exploration Inc. v. Unidentified, Shipwrecked Vessel, 675 F. Supp. 2d1126 (2009).
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In 2009, the Magistrate Judge Pizzo issued Report & Recommendations (R& R) in favour of the legal position of Spain. He concluded, on the balance ofevidence, the wreck was the Mercedes and “unquestionably” the property of
Spain

29）

. Under the FSIA, which set out the basis for US court jurisdiction overforeign States, a foreign State and its property are presumptively immune fromthe jurisdiction of the US courts unless an exception applied30）. Judge Pizzo

concluded that none of the exceptions put forward by OME was applicable andconsequently, the court was “without jurisdiction to adjudicate the claims,
against Spainʼs property”
items to Spain

31）. He recommended OME to return the recovered32）.

2. The Treatment of Sunken State Vessels in the UCH Convention
2.1

Drafting Process
The 1994 International Law Association (ILA) draft and 1998 UNESCO

draft of the UCH Convention excluded warships and other state-owned or
operated vessels and aircraft used for non-commercial purposes from the scopeof application of the Convention by following the approach of many maritime
treaties, due to its high political sensitivities. It meant that most of the UCH in
the world put outside of the protective framework of the Convention and that it
would seriously undermine the object of the Convention.
One of the obstacles to removing the exclusion was the provision in the1998 draft for abandonment “to be deemed” in certain cases. The application ofsuch a provision to state vessels was unacceptable to many States that strongly
insisted that their ownership rights could be lost only through an express
33）

abandonment

and it was dropped.

The preferable outcome for the maritime States would have been for theConvention to codify their stance on express abandonment and immunity by29） Odyssey case, op.cit., 675 F. Supp. 2d 1126, 1139.
30） FSIA, Section 1609.
31） Odyssey Marine Exploration Inc. case, op.cit., 675 F. Supp. 2d 1126, 1130.
32） There were other parties to file a claim against the res, such as Peru and 25 descendantsof passengers transporting goods on the Mercedes.
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providing that the express consent of the flag State would be required in allcases of proposed interference with sunken State vessels. However, a number of
Latin American and Caribbean States refused to recognize the title of the flag
State to colonial-era vessels in their coastal waters. They asserted that the UCH“is the property of the State in which it is found and through this it is the34）
heritage of the humanity ”. As a consequence, a specific regime for sunken
state vessels set out in the final text proved to be unacceptable to most ofmaritime States.
2.2 Definition of “State Vessels and Aircraft” and General Principle
Article 1(8) of the UCH Convention defines “state vessels and aircraft” tomean:[W]arships, and other vessels or aircraft that were owned or operated by aState and used, at the time of sinking, only for government non-commercial
purposes, that are identified as such and that meet the definition ofunderwater cultural heritage.
The definition is consistent with those in other Conventions, including
UNCLOS and Salvage Convention in 1989 and it excludes state-owned vesselsthat were engaged in trade or other private service.
With regard to sovereign immunity, there were concerns about the extent towhich any new convention would afford coastal State jurisdiction in respect ofState vessels. The final text of the Convention draws a compromise between theinterests of flag States and coastal States. In Article 2 (8), it is stated that:[N]othing in this Convention shall be interpreted as modifying the rules ofinternational law and State practice pertaining to sovereign immunities, nor33） S. Dromgoole and N. Gaskell, “Draft UNESCO Convention on the Protection of theUnderwater Cultural Heritage 1998”, International Journal of Marine and Coastal Law,
vol. 14 (1999) pp.186―7.
34） Adopted on 16 June 1998, in UNESCO, Background Materials on the Protection of theUnderwater Cultural Heritage, vol.2 (2000) pp.341―2.
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any Stateʼs rights with respect to its State vessels and aircraft.
2.3

Control Mechanisms in Each Maritime Zone
Despite of the Article 2(8), Maritime powers such as France, the UK,

Russia and US voted against the adoption of the UCH Convention. One of themain reason of this was that the Convention prepares some challenging
provisions with regard to the control mechanisms in each maritime zone,
especially in Article 7(3) and 10(7), and they understood that the text did notcover all their legal expectation as flag States protecting their sunken Statevessels, particularly their sunken warships.
One of the most controversial is the regime of the territorial waters. Article
7(3) states:
Within their archipelagic waters and territorial sea, in the exercise of theirsovereignty and in recognition of general practice among States, States
Parties, with a view to cooperating on the best methods of protecting Statevessels and aircraft, should inform the flag State Party to this Convention
and, if applicable, other States with a verifiable link, especially a cultural,
historical or archaeological link, with respect to the discovery of such
identifiable State vessels and aircraft. [Emphasis added.]In this Article, the problem is the use of term “should” rather than “shall” and it
is highly contentious. It means the notice to the flag State is not legally obliged
and no consent of the flag State is required to conduct activities directed at their
sunken State vessels.
The mechanism in the EEZ and continental shelf is also highly contentious.
Article 10(7) states:
Subject to the provisions of paragraphs 2 and 4 of this Article, no activity
directed at State vessels and aircraft shall be conducted without theagreement of the flag State and the collaboration of the Coordinating
State.
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It provides that no activity shall be conducted without the agreement of the flag
State, however, it made two exceptions in cases; first, emergency measures are
required to prevent “immediate danger” to UCH from “human activities or any
other cause, including looting”, in which case the consent of the flag States does
not have to be obtained first; second, the sovereign rights or jurisdiction of aState party in its EEZ or on its continental shelf may be interfered with unless it
takes action to prohibit or authorize activities directed at UCH located in thatzone.
In such cases, State party may prohibit or authorize those activities without
first consulting the flag State. It seems that this is in consistent with what Article2(8) provides and gives rise to the confusion. Flag States are bound to see thepossibility of a coastal States acting under one of these exceptions as an
infringement of their sovereign rights, and therefore, by using Article 2(8), they35）

may challenge the coastal Stateʼs right to act.

Conclusion
The UCH Convention seems to attempt challenging the existing
international law and State practices on the sovereign immunity issue in order toaccomplish the purpose of this Convention. It must be said, however, the UCH
Convention has failed to provide a satisfactory compromise between theinterests of flag States and coastal States on the issue and it is the major
obstacle to the ratification of the Convention by a number of States. In fact,
when the UK abstained from voting on the final text of the Convention, it notedthat the UK considers that “the current text erodes the fundamental principles
of customary international law, codified in [the UNCLOS] , of Sovereign
Immunity which is retained by a Stateʼs warships and vessels and aircraft….
until expressly abandoned by that State” and “the text purports to alter the finebalance between the equal, but conflicting rights of Coastal and Flag States,

35） S. Dromgloole, 2001 UNESCO Convention on the Protection of the Underwater Cultural Heritage, The International Journal of Marine and Coastal Law, vol.18, no.1 (2003)
p.74.
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36）” to theUK. It highlights a conflict between existing international law and the UCH
carefully negotiated in [the UNCLOS] in a way that is unacceptable

Convention.
In order to resolve such a conflict, it is needed to interpret once again
Article 2(8) which states “nothing in this Convention shall be interpreted as
modifying the rules of international law and State practice” (emphasis added) andobserve the building process of customary international law which is crystalized
through the accumulation of States practices. The UCH Convention has alreadyentered into force with more than 50 State parties. The Article 2(8) leaves theelaboration of the argument of the legal status of sunken State vessels and theirsovereign immunity in the future State practices for building of customaryinternational law and the Convention itself might have the possibility of theevidences of them, although several maritime States attempt to stop such a
stream by stating their position on the sovereign immunity of sunken Statevessels as mentioned above after the Juno and La Galga case and the Mercedes
case.
In observation, in the favor of the UCH Convention, of the process of
crystallization of customary international law on this issue, “cooperation among
States” which is the basic philosophy of the UCH Convention as it is stated in
its Preamble could be any key element. Cooperation, in fact, can be seen inseveral bilateral agreements as introduced above and might lead a new stream.
In this context, some special circumstances might give the wreck a particular
37）

status when it is considered to be either a human grave

or/and a historical orcultural site.
When we consider thousands of military vessels and aircraft lost during theFirst and Second World Wars in twentieth-century, they will have involved many
human fatalities and the primary concern of States will be to preserve thesanctity of the site and to ensure that any human remains are afforded36） “UNESCO Convention on the Protection of the Underwater Cultural Heritage: UK
Explanation of Vote”, United Kingdom Foreign & Commonwealth Office, 31 October
2001.
37） See M.J.Aznar-Gómez, op.cit., p. 224; R. Garabello, La Convenzione UNESCO sulla
protezione del patrimonio culturale subacqueo (2004) pp.317―21.
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38）
39）

appropriate treatment. The debate of this issue on sovereign immunity ofsunken State vessels should keep re-opening among States and their practices
are needed to be observed and examined.

38） S. Dromgoole, op.cit., p.134.
39） One of the Japanese main concerns is recovering remains in the naval battle site in the
Pacific War. See A. Iwabuchi, Bunka Isan no Nemuru Umi (The Seabed Where the Cultural
Heritage Lies), (2012) pp.88―90.
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