I. INTRODUCTION
Islands, as either sub-national political units or as the territory of continental or mainland States, raise multiple legal issues. These include foundational international law questions of territoriality and sovereignty, as well as in more recent decades, distinctive issues of self-determination and the human rights of their inhabitants. Many islands also raise unique constitutional and public law issues, either because of their status as sub-national political units or the bespoke legal status they have within a State including how constitutions may list island territories.Footnote 1 Such distinctive domestic arrangements may relate to the location and size of the island, its political history, or the cultural and linguistic diversity of the islanders themselves. This article conducts the first contemporary study of these issues and concludes that a legal era of islands is emerging.
Significant recent developments provide a foundation for that claim. In February 2019 the International Court of Justice (ICJ) issued an Advisory Opinion finding that the United Kingdom (UK) unlawfully separated the Chagos Islands from Mauritius in 1965 when both were colonial territories, holding that the UK is obliged to end ‘its administration of the Chagos Islands as rapidly as possible’.Footnote 2 Despite a subsequent United Nations (UN) General Assembly (UNGA) resolution stating that the Chagos Archipelago is part of Mauritius, and a ruling of the International Tribunal for the Law of the Sea (ITLOS) that the UK has no sovereignty over the Chagos Archipelago,Footnote 3 negotiations between the UK and Mauritius remain difficult. On the other side of the world, talks have proven more fruitful. On 10 November 2023, Australia and Tuvalu announced the ‘Falepili Union’.Footnote 4 The Union is a bespoke treaty negotiated at the request of Tuvalu, which meets the specific interests of Tuvalu while also reflecting Australia's strategic goals and objectives. Building upon a model of ‘Free Association’, the Agreement develops a distinctive ‘Union’ arrangement founded on three pillars, one of which effectively provides Australia with a veto over certain aspects of Tuvalu's foreign affairs. The Chagos dispute and the Falepili Union exemplify the broad range of international and constitutional legal questions raised by islands.
The increasing risks posed by climate change present more issues. In 2024 there is an Advisory Opinion request before the ICJ on the Obligations of States in Respect of Climate Change, which will in due course address questions of islands, climate change and sea-level rise. On 21 May 2024 ITLOS delivered its own response to a Request for an Advisory Opinion Submitted by the Commission of Small Island States on Climate Change and International Law (COSIS Advisory Opinion).Footnote 5 These developments highlight how the characterisation, legal status and future of islands are increasingly taking centre stage not only in international affairs but also in international and public law. In short, it can be asserted that a ‘legal era of islands’ is emerging which demands a clearer understanding of the distinctive legal issues islands raise.
In this article, the legal dimensions relating to islands are explored with the aim of developing an understanding of the international and constitutional legal status of islands. Section II begins by exploring key international legal questions. The first concerns characterisation. There has been much contemporary legal analysis and debate as to the distinction between islands and rocks, and there is also growing awareness of the significance of artificial islands and the distinctive issues they raise. While this article does not specifically address artificial islands,Footnote 6 the island/rock distinction and its significance for international law is considered. Islands were often discovered by colonial powers and title was assumed by formal proclamations and declarations and the publication of maps, followed by acts of administration, occupation and effective colonisation. Those actions did not always conclusively resolve issues of territoriality under international law, with the result that islands have been a focus of longstanding territorial disputes. Some have been settled peacefully, including through international legal processes, others have been the subject of armed conflict, while others remain disputed.Footnote 7 Some of the distinctive international legal issues associated with the maritime entitlements of islands under the law of the sea and the settlement of maritime boundaries will also be considered in this section.
Section III turns to the distinctive constitutional and public law issues raised by islands. Multiple legal processes have been adopted to accommodate islands—and islanders themselves—within the territory of a State. As will be demonstrated, this can extend from the island being simply incorporated within the public law of the State without any distinctive relationship, to the island being subject to some form of local government status, to the island being part of or the sole territorial component of a sub-national political unit. Different models are applied consistent with national legal systems and constitutional mechanisms, with the historical status of the island within the State and whether the islanders seek recognition of their cultural and other human rights emerging as significant factors. Nevertheless, as this study of the political status of islands illustrates, diversity is the rule. Section IV includes an initial analysis of the 2023 Australia–Tuvalu Union and the 2024 ITLOS Advisory Opinion, before Conclusions are drawn in Section V.
II. INTERNATIONAL LEGAL ISSUES
International law does not create a distinctive regime for islands in the same way that it does for the ocean in the law of the sea, or outer space in the various space treaties and instruments. Rather, international law has traditionally considered islands to be part of the land mass subject to international law, without distinguishing between various forms of land such as a continent, islands and rocks. It is possible to identify some distinctive international legal issues that arise regarding islands as a result of bespoke trading and financial arrangements that have been developed to allow for their economic growth and survival,Footnote 8 and environmental measures adopted to address in some instances their unique environments due to their rich biodiversity, location and isolation.Footnote 9 Islands have particularly been a focal point in seminal cases before both the Permanent Court of International Justice and the ICJ. Islands have also gained a distinctive position in international law under the 1982 UN Convention on the Law of the Sea (UNCLOS).Footnote 10 To begin this analysis it is appropriate to commence with some discussion of the characterisation of islands under UNCLOS, followed by issues associated with territoriality, and their maritime entitlements. This discussion informs the examination of constitutional legal issues in Section III.
A. Characterisation
The National Geographic identifies six different types of islands—continental, tidal, barrier, oceanic, coral and artificial.Footnote 11 These are all salt-water islands, and care must be taken not to exclude islands that are located in lakes and rivers, some of which have had significance in international law especially in boundary matters.Footnote 12 UNCLOS principally deals with islands in Part VIII, titled ‘Regime of Islands’.Footnote 13 Article 121(1) of UNCLOS defines an island as ‘a naturally formed area of land, surrounded by water, which is above water at high tide’. The characteristics of an island are therefore that it be: (i) naturally formed, and therefore cannot be artificial; (ii) comprised of land; (iii) surrounded by water; and (iv) above water at high tide. The following observations can be made regarding this definition. For the island to be naturally formed suggests that it has existed in some form or another for time immemorial, or it may have been recently formed as a result of natural events such as volcanic activity.Footnote 14 As such, an artificial island does not meet the relevant criteria, though a naturally formed island may be legitimately subject to land reclamation.Footnote 15 As to the nature of land comprising the island, there is nothing in international law requiring the island to be comprised of any particular natural materials. An island can be legitimately comprised of coral, gravel, rocks and sand or any combination of these and other natural substances.
An island does not lose its status because it is connected to the mainland, or to another island. Islands may be connected to another area of land by way of a bridge,Footnote 16 causeway,Footnote 17 or even a sandbar that is evident at low tide. Nevertheless, features that have the characteristics of an island and are connected to the mainland by a land bridge, are not true islands. This was a point of distinction with respect to the Hawar Islands in the Qatar v Bahrain case before the ICJ.Footnote 18 A critical component, and one that has gained increasing significance because of sea-level rise, is that the island must be above water at high tide. This distinguishes an island from other geographic features such as low-tide elevations referenced in Article 13 of UNCLOS. The island must therefore be permanently above water at all times. The consequence is that an island may lose its status as a result of sea-level rise, which in turn raises issues of land reclamation and the building of sea barriers and walls in an effort to keep out rising water levels.Footnote 19 These elements of Article 121(1) comprise a juridical island for the purposes of UNCLOS and the law of the sea. A juridical island enjoys the same maritime entitlements as a continental landmass, and territory located within a continental landmass. This includes under Article 121(2) of UNCLOS a 12-nautical mile (nm) territorial sea, a 24-nm contiguous zone, and a minimum entitlement to a 200-nm continental shelf and an exclusive economic zone (EEZ).
An aspect of the definition of a juridical island that has been the focus of attention is that no reference is made in Article 121(1) of UNCLOS to the size of the feature. This is relevant for the purposes of Article 121(3) which refers to rocks as follows: ‘Rocks which cannot sustain human habitation or economic life of their own shall have no exclusive economic zone or continental shelf.’ This effectively recognises that in addition to juridical islands, there exists a sub-category of islands—juridical rocks—which, while being a naturally formed area of land and surrounded by water and above water at high tide do not enjoy the same maritime entitlements as juridical islands. That distinction has become increasingly significant because of UNCLOS and the vast maritime entitlements it grants to land features which far exceed those that were originally envisaged and recognised under the law of the sea post-World War II,Footnote 20 and as originally recognised in the 1958 Geneva Conventions.Footnote 21
International courts and tribunals have given only limited consideration to the elements that distinguish juridical islands from juridical rocks under UNCLOS, with the leading authority being the 2016 South China Sea Arbitration between the Philippines and China.Footnote 22 For the purposes of this review, what can be observed is that the critical issue is the natural capacity of the land to support and economically sustain an indigenous or non-indigenous population creating a community of people who call the island their home.Footnote 23 Consequently the size of the feature may become determinative as to whether it is assessed as being an island or a rock. Rockall, located off the northwest coast of Scotland, provides an example of a State (the UK) adjusting its position from asserting that feature to be an island, to its current position that it is a juridical rock.Footnote 24 Though Anderson has asserted ‘there are no rules regarding minimum sizes for islands’,Footnote 25 in many instances size will be determinative of the juridical status of an island and this is reflected in State practice. Maritime boundary delimitations are an indicator of such State practice, where the delimiting States have negotiated boundaries that reflect the juridical status of an island which in turn has been recognised de facto or de jure by other States.Footnote 26 While the tribunal in South China Sea unanimously determined that all of the contested features were not islands and were either juridical rocks or low-tide elevations, China has not accepted that decision.Footnote 27 Nevertheless, the Award gave considerable clarity as to how Article 121(3) is to be interpreted.
A further issue of characterisation is whether a group of islands comprises an ‘archipelagic State’ consistently with Article 46 of UNCLOS. The status of mid-ocean archipelagos was unresolved following the 1958 First UN Conference on the Law of the Sea.Footnote 28 However, during the 1960s Indonesia and the Philippines actively promoted the recognition of certain islands as archipelagic States, and this was eventually reflected in Part IV of UNCLOS.Footnote 29 For an island State to assert archipelagic status consistently with UNCLOS, the State must be wholly comprised of one or more archipelagos which together ‘form an intrinsic geographical, economic and political entity, or which historically have been regarded as such’.Footnote 30 To be able to enjoy the status of an archipelagic State, the main islands comprising the archipelago must be capable of being connected by archipelagic baselines drawn according to a very precise UNCLOS formula.Footnote 31 To date, 22 island States have been able to attain the status of recognised archipelagic States extending from the very largest of the group in Indonesia and the Philippines, to the much smaller Saint Vincent and the Grenadines, and Grenada.Footnote 32 Because of the UNCLOS archipelagic baseline constraints, Japan and New Zealand, for example, are not entitled to archipelagic status. Likewise, Hawaii does not enjoy archipelagic status due to it being a geographical unit of the continental United States (US). The law of the sea significance for archipelagic States is that the waters that fall on the landward side of the archipelagic baselines are ‘archipelagic waters’ over which the State enjoys extensive sovereignty akin to internal waters excepting for the navigational rights of foreign vessels. In addition, the archipelagic State can assert all of its maritime entitlements from the archipelagic baselines, which extends the outer limits of all its maritime zones.
B. Territoriality
Islands have been the subject of some of the most significant decisions of international courts and tribunals dealing with territoriality. Decisions pre-dating the UN Charter dealt with the territorial claims and entitlements of colonial powers that were distant from their metropolitan territories. Post-1945 decisions gradually began to focus more on newly independent States, and contemporary island territorial disputes before international courts and tribunals are between parties that have emerged as a result of decolonisation, but who are seeking to reconcile island territorial disputes over colonial boundaries. There remain important exceptions to this general characterisation, as highlighted above by the dispute over the status of the Chagos Archipelago,Footnote 33 and the ongoing disagreement between Argentina and the UK over the Falkland/Malvinas Islands.Footnote 34
The earlier cases dealing with territoriality and islands often addressed what at the time were remote and isolated islands, especially for the colonial powers. This included Palmas (Miangas) Island (USA v Netherlands) (1928)Footnote 35 in the Celebes Sea south of the Philippines, Clipperton Island (France v Mexico) (1932)Footnote 36 1,120 km offshore the Mexican coast in the Pacific Ocean, and Greenland (Denmark v Norway) (1933).Footnote 37 The decisions in these cases laid down important principles with respect to how discovery of an island only confers an inchoate title, which requires more activity and conduct from a claimant to perfect a title over distant islands, and that a different standard is applicable to polar lands incapable of the same level of occupation as more temperate lands and islands. While islands have gradually become less isolated due to advances in transportation and technology, the principles laid down in these cases have continued to have resonance in more contemporary island territorial disputes determined by the ICJ.Footnote 38
The principles developed over time from what is now nearly 100 years of jurisprudence and associated State practice remain significant in some prominent island disputes that remain unsettled. Examples are Dokdo/Takeshima between Japan and South Korea, the Matthew and Hunter Islands between France and Vanuatu, and the Senkaku/Diaoyu Islands between China and Japan. While some of these territorial disputes appear intractable, there are contemporary examples of States settling island territorial disputes through diplomacy. A long-running, albeit relatively minor, island territorial dispute existed between Canada and Denmark over uninhabited Hans Island/Tartupaluk in the Nares Strait between Ellesmere Island (Canada) and Greenland. The dispute only became apparent in 1973 as a result of the need to delimit the maritime boundary in the strait. After nearly 50 years of friendly exchanges and negotiations which recently actively involved Greenland and Canadian Inuit, in 2022 an innovative and elegant solution was reached on a boundary that effectively divided the island between Canada and Denmark.Footnote 39
The international law resolving territorial disputes over islands needs to be seen against the backdrop of the general international law of territoriality. Contemporary international courts and tribunals make little distinction between territorial disputes over different types of lands, territorial disputes between continental and island States,Footnote 40 and whether an island is proximate or distant from a coast or located mid-ocean.Footnote 41 What can be observed is that in the case of some island territorial disputes the legacies of twentieth-century conflict loom large. This is especially the case with islands that were removed from Japanese control under the 1951 San Francisco Peace Treaty,Footnote 42 and which have resulted in ongoing tensions between Japan and its neighbours. Colonial and post-colonial interests over islands have also been significant, as is evident in disputes in the Indian (Chagos Archipelago), Pacific (Matthew and Hunter Islands) and Atlantic (Falklands/Malvinas) Oceans. What has also become a significant impetus for seeking resolution of island territorial disputes, because of the contemporary importance attached to islands beyond their land mass, is their maritime entitlements generated under UNCLOS, which are discussed below.
C. Maritime Entitlements
As noted above, providing a feature is a juridical island, which also includes archipelagic States, it will enjoy the full suite of UNCLOS maritime entitlements, subject only to constraints of geography arising from neighbouring adjacent or opposite continental lands or other islands. What has been underappreciated as a result of developments in the law of the sea and UNCLOS especially has been the potential maritime entitlements that a juridical island enjoys. As Prescott and Schofield have observed:
If no maritime neighbours were within 400 nm of the feature, an island has the potential to generate 125,664 nm2 (431,014 km2) of territorial sea, EEZ and continental shelf rights, making the potential value of disputed islands difficult to underestimate.Footnote 43
The importance of location of islands and the constraints imposed by geography are highlighted by comparing Singapore (an island of 709 km2 and a maritime zone of 714 km2) with Nauru (an island of 21 km2 and a maritime zone of 309,261 km2).Footnote 44 Notwithstanding Nauru's much smaller size, it enjoys a maritime entitlement that is over 400 times greater than that of Singapore. Some small island States can therefore enjoy very significant maritime entitlements that are considerably larger than those of coastal continental States whose maritime entitlements are constrained by geography and their settled maritime boundaries.
Two issues arise from this dynamic that are important for islands, and island States in particular. The first is to ensure a juridical island gains its full suite of maritime entitlements consistent with UNCLOS.Footnote 45 For island States principally comprised of a number of large co-located islands this may not be too challenging, such as in the case of New Zealand and the UK. However, for island States comprising many islands separated by some considerable distances this can be problematic. These island States will have a particular incentive to ensure that they gain their maximum maritime entitlements, particularly because of the economic and resource benefits that may arise from access to fish stocks and seabed resources. The distinction between juridical islands and juridical rocks noted above can become significant in some instances. Over the past 20 years this dynamic has been particularly highlighted in diplomatic exchanges before the Commission on the Limits of the Continental Shelf (CLCS). The CLCS is an UNCLOS institution tasked with assessing and making recommendations to coastal States regarding their continental shelf entitlements consistent with Article 76 of UNCLOS. Submissions before the CLCS have sought to assert continental shelf entitlements from juridical islands which have been challenged by other States in diplomatic exchanges via the UN Secretary-General.Footnote 46 The most prominent instance of such a diplomatic challenge arose in the case of Japan's claim that Okinotorishima, an atoll located approximately halfway between Okinawa and Guam, is a juridical island entitled to a continental shelf.Footnote 47 However, as the CLCS is a scientific body it has no capacity to resolve legal issues associated with the characterisation of a feature as either a juridical island or a juridical rock.Footnote 48
Islands can also potentially distort the direction of a maritime boundary, especially when a small island is located offshore of a mainland coast. When confronted with these geographical challenges international courts and tribunals have typically sought to diminish the impact an island or islands have upon the direction of a maritime boundary in order to achieve an equitable solution consistent with UNCLOS.Footnote 49 Multiple variables are taken into account including the size and population of the islands, economic and historical factors, the impact granting islands their full maritime entitlement would have on the direction of the maritime boundary, and if the coastal States are continental or island States.Footnote 50
A particular environmental issue for islands in recent decades has been the impact of climate change, and the consequences for certain islands of associated sea-level rise. Additional environmental impacts arising from these events are saltwater inundation, crop failures, environmental damage from storm surges, and fish-stock migration.Footnote 51 This has resulted in small island States particularly taking a proactive position on climate change in various international fora, including the UN and before international courts and tribunals. In 2024 both the ICJFootnote 52 and ITLOSFootnote 53 have considered Advisory Opinion requests actively promoted by small island Caribbean and Pacific States. The outcome of those proceedings may have a profound impact on how the international community views the legal consequences of climate change and the legal obligations that developed States may owe small island States.
A very particular concern for some island States has been the potential impact of sea-level rise on their maritime entitlements.Footnote 54 Sea-level rise will result in adjustments to the normal baseline from which all maritime entitlements are asserted, and features such as rocks, reefs, and low-tide elevations relied upon for the drawing of straight baselines may become subsumed.Footnote 55 There is a real prospect that some islands and parts of island States may be left permanently underwater. This would have an impact on the status of archipelagic States and require revisiting of archipelagic baselines.Footnote 56 In response to the lack of legal certainty as to how to respond to this phenomenon, in 2021 the Pacific Islands Forum (PIF) and the Alliance of Small Island States issued separate Declarations calling for the stability of baselines under UNCLOS.Footnote 57 These small island States have made a plea for the recognition of their very particular situation, the impact that sea-level rise will have on their maritime entitlements, and the need for legal certainty. Since their circumstances remain under active consideration, a final legal resolution of these issues has yet to be reached.
III. CONSTITUTIONAL LEGAL ISSUES
Islands are a valuable unit of study to explore a range of constitutional legal issues. Geographic separation can nurture a unique sense of identity distinct from neighbouring territories. Where an island falls within a larger political community, that distinctive identity may create pressure for discrete political and legal arrangements that differ from other regions within the State. These arrangements could provide for enhanced degrees of autonomy or self-administration, or recognise the cultural, linguistic and other human rights of the islanders themselves.Footnote 58 In short, the character of islands qua islands leads to more varied constitutional settlements than mainland territories.
The legal and political autonomy of islands can be mapped along a spectrum. At one end can be placed islands entirely integrated within the metropole with no unique constitutional or political status, while at the other end sit independent sovereign States that happen to be islands (such as the Pacific island State of Nauru).Footnote 59 Within this band an incredible variety of constitutional and legal arrangements existFootnote 60—one study suggests that more than 100 sub-national island jurisdictions ‘are known to enjoy a degree of autonomy without sovereignty’.Footnote 61 This section provides an overview of this diversity through an illustrative survey of the political status of island territories.Footnote 62
Two points should be borne in mind at the outset. First, examining the political status of islands is akin to taking a snapshot in time; the legal relationship between islands and their metropole is a story of change and adaptation, and not simply in one direction. Indeed, despite confident predictions in the 1980s that a flurry of sub-national islands would soon pursue independent Statehood,Footnote 63 the opposite has occurred. However, this does not mean that islands have largely been content to cede control and decision-making to the metropole; rather, many have instead opted to pursue greater autonomy within their existing State.Footnote 64
Second, processes of colonisation, human migration, and political and strategic concerns challenge easy analysis. Consistent with their malleable relationship, there is no simple formula for devising an appropriate status. More common are countless sui generis arrangements that have emerged in the interaction between island and metropole, and which do not fit neatly into a schematic framework. As Eve Hepburn notes, a ‘plethora of terms’ characterises these arrangements, including autonomous province, associate State, overseas territory, special region, external territory, overseas department, federal province, and autonomous region.Footnote 65 Such terminology can obscure rather than illuminate the division of legislative and executive responsibilities in each case.
A. No Distinct Political Status
Islands are detached physically from mainland States, but they are not always detached politically.Footnote 66 Indeed, many islands have no unique constitutional or political status within the State that exercises jurisdiction and authority over the territory. Often this appears to be a consequence of geographic and population factors. Lightly populated islands proximate to a mainland coast may be less likely to be governed under distinct arrangements. This is the case for many islands off the coast of Australia, including North and South Stradbroke Islands (Queensland), Bruny Island (Tasmania), Kangaroo Island (South Australia) and Rottnest Island (Western Australia). It is not always true, however. The island of Sandwip along the south-eastern coast of Bangladesh is home to around 450,000 people but enjoys no distinctive status within Bangladesh. Similarly, no distinctive status is afforded to the North and South Islands of New Zealand.
Historical factors may also complicate the search for bright line rules. In the UK the lightly populated Isles of Scilly off the southwest of Cornwall are administered under a sui generis form of local government,Footnote 67 which can be traced to the islands’ strategic position during the Middle Ages.Footnote 68 Similarly, the Channel Islands off the French coast are remnants of the Duchy of Normandy and are largely autonomous political communities, though part of the English Crown.Footnote 69 In contrast, the more heavily populated Isle of Wight which lies closer to the mainland in the English Channel is treated in the same manner as all other local authorities.Footnote 70
Islanders may chafe against the absence or abolition of distinctive arrangements. Consider the case of Norfolk Island, an Australian external territory which lies some 1,400 km off the mainland in the Pacific Ocean between New Zealand and New Caledonia. In 1979, the Australian Parliament conferred self-government on Norfolk Island.Footnote 71 The Act provided for an Administrator, appointed by the Governor-General of Australia, and an Executive Council and Legislative Assembly, elected by residents. The Assembly was empowered with a broad range of responsibilities that were supplemented over the years.Footnote 72 The Territory could enact legislation covering subjects consistent with local government, such as roads, rubbish and fencing, as well as larger ‘national’ subjects, such as postal services and civil defence, as well as fields such as environmental protection, criminal law and public works.Footnote 73 In areas in which the national government had a particular interest, such as fishing, immigration and social security, the Commonwealth Minister for Territories exercised an oversight function.Footnote 74 In 2015, however, the Territory's Legislative Assembly was abolished and its self-government powers removed.Footnote 75 Today, Norfolk Island is run by an Administrator appointed by the Governor-General of Australia and an elected advisory council exercising limited powers of local government in line with arrangements on the mainland. On the island, many continue to advocate for reform, including adding Norfolk Island to the UN list of non-self-governing territories.Footnote 76
B. Delegated Autonomies
A central government may confer a degree of political or governmental authority beyond local government powers on an island jurisdiction. Once again, a wide spectrum exists. In some cases, a government may establish a special economic zone (SEZ) on a portion of their territory, that may or may not encompass an entire island.Footnote 77 In other cases, a unitary State may delegate certain substantive functions and responsibilities in view of the inhabitants’ distinctive culture, administrative efficacy or due to larger strategic and political factors. Often any delegation is limited, providing minimal powers of self-government, and ensuring the metropole retains considerable authority. However, as will be seen, in a few cases, a unitary State may devolve substantial legislative and executive power to an island community. Delegation may be set out solely in legislation or have constitutional backing.
Some islands might form an SEZ. SEZs are geographically delineated autonomous regions within States that operate under distinct rules, particularly around taxation, customs and labour regulations.Footnote 78 While SEZs are not confined to islands, owing to their geographic delineation islands are particularly apt hosts. In some cases, an SEZ may not have its own legislative competences, but rather administer distinctive laws enacted by the central government. For example, the small Iranian islands of Kish and Qešm in the Persian Gulf are both free-trade zones which are administered semi-autonomously.Footnote 79 Many other cases exist. The Honduran Island of Roatán, for instance, is home to a libertarian-inspired SEZ under which an investing company is permitted to impose and collect taxes, incur debts, establish its own education, health, civil service and social security systems, and impose property taxes.Footnote 80 An earlier version of this regime even allowed companies to engage in international relations. In other cases, particularly in more populated territories, an island SEZ may have a greater degree of legislative and executive responsibility. For instance, the Chinese island of Hainan is both a province with its own (minimal) legislative powers and an SEZ. So too is the Archipelago of San Andrés, Providencia and Santa Catalina in Colombia.
The variety of delegated authority that islands may exercise is usefully illustrated by the ‘kaleidoscope’Footnote 81 of different legal statuses of the French Overseas Territories. There are 13 territories outside Europe administered by France with five broad legal designations: (1) départments et regions d'outre-mer (DROM); (2) collectivités d'outre-mer (COM); (3) pay d'outre-mer au sein de la République (POM); (4) the sui generis territory of New Caledonia; and (5) uninhabited territories.Footnote 82 The DROM territories include the Caribbean islands of Guadeloupe and Martinique, the Indian Ocean islands of Mayotte and Réunion, and French Guiana (on the northern coast of continental South America). Article 73 of the French Constitution confirms that DROM territories have no distinct legal status—they have the same powers and responsibilities as France's mainland regions.Footnote 83 DROM residents are French citizens, send representatives to the National Assembly, and are subject to the same laws and regulations as metropolitan France. However, amendments in 2003 and 2008 tentatively expanded the capacity of elected DROM Regional Councils to modify certain laws and regulations relating to ‘the particular characteristics and constraints’ of each territory.Footnote 84 Nevertheless, this procedure is not available for ‘national’ laws, such as those relating to civil rights, the administration of justice and criminal law. Owing to strategic concerns, even this limited degree of autonomy is expressly denied to Réunion.Footnote 85
Unlike DROM, COM/POM enjoy a degree of legislative autonomy.Footnote 86 Despite the different terminology, the legal status of COMs and POMs is identical. There are four COMs and one POM: the Pacific islands of French Polynesia (POM), and Wallis and Futuna (COM), the Caribbean islands of Saint Barthélemy (COM), the French half of the island of Saint Martin (COM), and the Atlantic Ocean islands of Saint Pierre and Miquelon (COM).Footnote 87 Each community elects a Legislative Assembly that is empowered to pass laws, except in areas of national concern, such as foreign affairs, defence, currency and security.Footnote 88 This is not a federal system, however.Footnote 89 These political units do not have their own constitutions; although their status is guaranteed in the French Constitution, the authority they exercise is conferred by statute and therefore subject to revision by the National Assembly.
Similar varied arrangements exist for the British Overseas Territories (BOTs), the US Overseas Territories, and the Dutch Caribbean which will each be considered in turn. The UK does not formally differentiate between its overseas territories, classifying each as a BOT. There are 14 BOTs, 11 of which are permanently inhabited.Footnote 90 Excluding Gibraltar and the Sovereign Base Areas of Akrotiri and Dhekelia (on Cyprus) leaves nine permanently inhabited BOTs that are also islands.Footnote 91 The Overseas Territories are separate to the UK and have their own Constitutions.Footnote 92 The British monarch is the head of State and appoints a representative on the advice of the British government to exercise executive power in each territory. However, the monarch acts in his role as king of each territory rather than King of the UK,Footnote 93 meaning territorial governors act on the advice of the territory's executive, and the UK government is not able to disallow legislation passed by territorial legislatures.Footnote 94 Nevertheless, the UK Parliament retains the authority to expand or contract the powers and self-governing authority of BOTs. While each permanently inhabited BOT enjoys a degree of representative government that exercises powers delegated by the UK Parliament, the size and scope of government is correlated to the population and political development of each territory. For instance, although Bermuda enjoys ‘almost complete internal self-government’, in Tristan da Cunha and the Pitcairn Islands ‘the Governor is the law-making authority and there are only advisory councils’.Footnote 95 In all BOTs, the UK remains responsible for defence and external affairs, though some aspects of the latter have been delegated to the larger territories.
The US characterises territories neither part of a State nor Federal district as an ‘insular area’. This generic term encompasses considerable diversity; an insular area may be organised or unorganised, and incorporated or unincorporated. Organisation relates to self-government; organised territories are lands under federal authority that have been granted a degree of self-governance by Congress through an Organic Act, while unorganised territories are directly administered by the federal government. Even for organised territories, however, Congress retains plenary power to revise the delegation of legislative and executive responsibilities.Footnote 96 An organised territory that has established a more developed political relationship with the federal government is classified as a Commonwealth. Incorporation relates to the application of the US Constitution. The Constitution applies in its full extent to incorporated territories; in unincorporated territories Congress has determined that only selected aspects of the Constitution apply.Footnote 97
The US possesses five permanently inhabited island territories: Puerto Rico and the US Virgin Islands (Caribbean Sea), Guam and the Northern Mariana Islands (North Pacific) and American Samoa (South Pacific). All five territories are unincorporated. Each is organised except for American Samoa,Footnote 98 while Puerto Rico and the Northern Mariana Islands are Commonwealths. Notwithstanding these distinctions, each territory has a locally elected legislature and executive and exercises a degree of political autonomy. For the two Commonwealths, this appears extensive—the legislative power of the Northern Mariana Islands, for instance, extends to ‘all rightful subjects’.Footnote 99 Nevertheless, ultimate governance authority is vested in the US Congress and the President—institutions within which Territory residents have no direct influence. Citizens may elect a non-voting delegate to the US House of Representatives but have no representation in the Senate and do not vote for the President.Footnote 100 As many have noted, the peculiar relationship these insular areas have with the federal government remains ‘essentially colonial’.Footnote 101
The Dutch Caribbean consists of six entities divided into two political collectivities.Footnote 102 The islands of Bonaire (in the Leeward Antilles off the coast of Venezuela), and Sint Eustatitus and Saba (in the Lesser Antilles group) (known as the BES islands) are formally ‘public bodies’, or special municipalities within the Netherlands proper.Footnote 103 This arrangement aims at integrating these territories into the metropolitan Netherlands while recognising that geographic, demographic and administrative factors necessitate distinct measures. Dutch laws do not automatically apply to the territories; the Dutch government chooses when and how metropolitan laws are to be implemented.Footnote 104 Similarly, powers of governance and administration are shared between elected island councils headed by a mayor appointed by the Dutch Crown, and the central government's National Office for the Caribbean Netherlands. Nevertheless, ‘inherent inequalities’ in resources, capacity and political power mean that relations between these institutions are ‘characterised by huge asymmetries’.Footnote 105 In contrast to the BES islands which have sought integration, the Caribbean territories of Aruba, Curaçao and Sint Maarten (the southern half of the French COM) have pursued greater autonomy. Alongside the Netherlands itself, each is a constituent country within the Kingdom of the Netherlands.Footnote 106 Given this arrangement is more akin to a federal structure, the political status of these islands is considered in more detail below.
Even within unitary States, many islands may exercise substantial powers of autonomy. This could be a result of one of several factors. In cases of decolonisation, a central government might accede to the demands of residents to devolve legislative and executive powers in view of the cultural and ethnic distinctiveness of the inhabitants. This may eventually lead to separate Statehood but could also remain at the level of a federacy.Footnote 107 In other cases, international legal instruments may guarantee the island's autonomy, inhibiting the central government from undertaking certain actions. Relatedly, the central government may have only recently assumed effective control of an island jurisdiction and may be in the process of regularising its administration.
The island of Greenland, or Kalaallit Nunaat in Greenlandic, illustrates the first approach. Governed by Denmark as an overseas colony from 1814,Footnote 108 Greenlanders had little influence over the development of their island. Following the conclusion of World War II, Greenland was listed as a ‘non-self-governing territory’ under Chapter IX of the UN Charter. In 1953, this status was terminated as Greenland was integrated into the Kingdom of Denmark as a county, and Greenlanders obtained the same legal rights and entitlements as Danish citizens.Footnote 109 In the years since, however, Greenland has steadily sought and gained substantive autonomy. In 1979, the island was granted home rule,Footnote 110 and assumed legislative and executive authority over a wide range of domestic domains, including taxation, fisheries, education, cultural affairs and environmental protection, while Denmark retained authority over the Constitution, foreign policy, currency, the judicial system and defence.Footnote 111 Even so, Greenland enjoyed some degree of distinctive foreign relations: in 1985 the island left the European Economic Community.Footnote 112 Autonomy was subsequently extended further. Under the Greenland Self-Government Act 2009, the island took control of law enforcement and the legal system, as well as natural resources,Footnote 113 and gained the capacity to negotiate and conclude international agreements that exclusively concern the island.Footnote 114 The Act also allows Greenland to pursue independent Statehood if it so desires.Footnote 115 A similar regime applies to the Faroe Islands, an autonomous Danish territory located in the North Atlantic Ocean between the UK, Norway and Iceland. For islands like Greenland, the process of decolonisation may eventually lead to independence and separate Statehood. Although islands subject to political contestation are not the focus of this study, examples exist, including New Caledonia (France) and Bougainville (Papua New Guinea).
The Åland Islands exemplify the second category. Åland is an archipelago in the Baltic Sea between Finland and Sweden. The largely Swedish-speaking Finnish territory consists of around 30,000 people across more than 6,500 islands (60–80 are inhabited). Åland's location is strategically significant and various Nordic and European powers have exercised authority over the archipelago since the twelfth century, with Sweden holding sway for most of this period. In 1809, Sweden ceded Åland to the Russian Empire, which formally incorporated the region into the semi-autonomous Grand Duchy of Finland.Footnote 116 In 1917, Finland declared independence, and Åland residents petitioned the new government to allow them to join Sweden. Finland declined to cede the territory. The dispute was ultimately resolved by the League of Nations in 1921, which held that Finland must guarantee the right of residents to maintain the Swedish language, as well as their own culture and local traditions.Footnote 117 Åland thus enjoys significant autonomy under both Finnish and international law. The Åland Self-Government Act outlines the areas in which the Åland Parliament and Provincial Government exercise responsibilities. The main areas are education, culture, the environment, health, local government, police and communications. Finnish laws apply in most areas of civil and criminal law, courts, customs and taxation.Footnote 118 In other areas, such as shipping, Finland and Åland share legislative power.Footnote 119 The islands also exercise a limited degree of international relations: Åland is a member of the Nordic Council and has its own postage stamps.Footnote 120 The islands elect one representative to the Finnish Parliament.
Hong KongFootnote 121 and Macau illustrate the third approach. A British colony was established on Hong Kong Island in 1841 during the First Opium War between the British and Qing Empires, but the island was not formally ceded to the UK until the 1842 Treaty of Nanking. In 1984, following several years of discussions, the UK and People's Republic of China (PRC) agreed that the colony would be transferred to Chinese control on 1 July 1997.Footnote 122 Under the treaty, the PRC accepted that Hong Kong would retain a significant degree of legislative and executive autonomy as a ‘Special Administrative Region’.Footnote 123 Hong Kong maintains its own government, legislature, legal system, police force, immigration policies, national sports teams, customs territory, and substantial competence in external affairs.Footnote 124 Hong Kong also has a limited international presence. It is a member of the World Trade Organization and may conclude and implement international agreements in areas such as shipping, fishing and communication. However, consistent with the transfer, ultimate authority rests with the National People's Congress in Beijing. In 2017, the PRC declared it considers the treaty is no longer of any legal effect.Footnote 125 In recent years, the central government has sought to exercise greater control over the island, limiting Hong Kong's autonomy.Footnote 126 The former Portuguese colony of Macau has a similar history and contemporary political status.
C. Federations
A federation is distinct from a unitary State. A unitary State may devolve certain functions and responsibilities to a sub-national region, but the national government retains the capacity to alter or revoke any delegated authority unilaterally. In contrast, a federation is a political entity composed of self-governing regions that retain certain powers not exercisable by the national government.Footnote 127 The division of powers is constitutionally entrenched and cannot be unilaterally altered. Nevertheless, although autonomy sits on a firmer legal footing (except in cases like the Åland islands where it is protected by international law), this does not necessarily mean it is more substantive in practice. It is important to understand the precise division of legislative power between the centre and its peripheries. As will be seen, even within federal systems, diversity is the rule.
Federal systems can be divided several ways. One approach focuses on the respective powers of each constituent political unit. Under systems of symmetric federalism, such as Australia and the US, each political unit possesses equal powers of self-rule and shares identical legal entitlements in institutions of shared rule. In asymmetric federations, conversely, constituent political units enjoy varied degrees of legislative and executive autonomy and/or dissimilar representation in central institutions. Asymmetry may emerge because one or more sub-State communities is more powerful, influential, or insistent on attaining or ensuring measures of political autonomy.Footnote 128 Given that their geographic isolation and relatively smaller population often leads islands to develop and maintain a distinctive culture, asymmetrical federalism may be particularly appropriate.
A federation may be comprised entirely of islands. The Union of the Comoros is situated in the Mozambique Channel in the Indian Ocean between Madagascar and the African mainland. Having proclaimed its independence from France in 1975, the Union comprises the three main islands of Grande Comore, Anjouan and Mohéli, and a number of smaller islands. Reflecting the political history of the Comoros, each major island has significant legislative and executive autonomy. The three islands elect their own parliament and government and enjoy executive and legislative authority in areas not assigned to the Union government.Footnote 129 More commonly, a federal State may comprise a mix of territories on a mainland and one or more discrete islands with identical legal and political status. Numerous examples exist, including Australia (Tasmania), the US (Hawaii) and Canada (Prince Edward Island).
In practice, many federations combine aspects of both symmetry and asymmetry. The island of Tasmania is a constituent political unit of Australia, and it enjoys an identical degree of self-rule as sub-State communities on the mainland such as Victoria and Queensland. However, no other Australian island is treated similarly. The inhabited islands of Norfolk Island, Christmas Islands and Cocos/Keeling Island, among others, are formally designated external territories. They possess no legislative powers, are administered by authorities on the mainland and have no direct representation in shared-rule institutions. Similar arrangements exist in the US. While Hawaii achieved statehood in 1960, other islands, such as Puerto Rico and Guam, are unincorporated territories. Although these islands have some degree of autonomy (unlike Australia's external territories), powers are not inherent but delegated and subject to the US government.Footnote 130
The islands of Aruba, Curaçao and Sint Maarten (the southern half of the French COM) inhabit a curious position. These three territories are, alongside the Netherlands itself, constituent countries within the Kingdom of the Netherlands. Each has their own legislature and government empowered to manage their own affairs independently,Footnote 131 while the Kingdom is responsible for administering laws relating to foreign relations, nationality, safeguarding fundamental human rights, and other similar fields.Footnote 132 Although suggestive of a federation comprising four autonomous and equal countries, the significant disparities in economic strength and population size between the Netherlands (which accounts for 98 per cent of the population of the Kingdom) and the Caribbean communities mean that in practice the Netherlands dominates Kingdom affairs. This is also reflected in the absence of true shared-rule institutions: there is no Kingdom Parliament; the Council of Ministers of the Kingdom comprises a Minister Plenipotentiary from each Caribbean country and the entire Netherlands cabinet; and the Netherlands Supreme Court is the ultimate judicial authority for legal disputes. Considering these and other features, Dutch constitutional scholars have described the relationship as a ‘quasi- or pseudo-federation or of a sui generis construction’.Footnote 133 Within the Caribbean countries themselves, it is often not clear ‘who is in charge, the government of the Netherlands or the Kingdom government?’.Footnote 134
D. Associated States
The regimes considered thus far encompass sub-national island political communities that enjoy varied degrees of autonomy within a metropolitan State. They are not independent, even if they possess significant authority. Islands within this fourth category fundamentally differ in legal status: they are independent States. Nonetheless, the exercise of their autonomy may be more constrained in practice.
Independent States may negotiate relationships with larger powers, ceding certain attributes of sovereignty, responsibilities, or functions ‘in exchange for benign protection’.Footnote 135 While this does not impinge upon the sovereign status of the smaller State as they retain the authority to revoke or alter the agreement, it does affect their capacity to exercise the full range of sovereign functions. Such agreements are not confined to islands—under the Treaty of Vicinage, for instance, the European State of Andorra has agreed not to act inconsistently with the ‘fundamental interests’ of France or Spain.Footnote 136 Nevertheless, several remote islands small in population and territory have sought to exploit ‘the advantages of both sovereignty and an autonomy supported by a benign patron state’.Footnote 137
There are five States currently in free association with a larger power, all located in the Pacific Ocean. They are the Cook Islands and Niue (New Zealand), and the Marshall Islands, Micronesia, and Palau (US).Footnote 138 The three States associated with the US are UN Member States, but the Cook Islands and Niue are not. Indeed, these two States have a peculiar international legal status. Consider the Cook Islands as an example.
Under the terms of their agreement, the Cook Islands has full autonomy over its internal affairs, but New Zealand is responsible for its defence and may support and assist the Cook Islands to engage in external affairs.Footnote 139 This legal relationship has left the international legal status of the Cook Islands somewhat unclear. The New Zealand Ministry of Foreign Affairs and Trade issued a memo in 2005 declaring that ‘the Cook Islands has developed a separate international identity from that of New Zealand’ but cautioning that it did not consider that ‘the Cook Islands is, in constitutional terms, an independent sovereign state’.Footnote 140 James Crawford also noted in passing that the Cook Islands is not a State but has some degree of ‘separate international status’.Footnote 141 At the same time, New Zealand courts have found that ‘the Cook Islands is a fully sovereign independent state and that the special relationship between the Cook Islands and New Zealand does not affect this issue’.Footnote 142 The Cook Islands has been admitted to a range of UN agencies, including the World Health Organization, membership of which is open to ‘all States’.Footnote 143 It also maintains diplomatic relations with 52 States and the European Union, and is a party to several international treaties. Although not a UN member—New Zealand does not support membership—the Cook Islands is characterised as a ‘non-member state’,Footnote 144 and for all intents and purposes appears to be a State.Footnote 145 Nevertheless, there is no Cook Island citizenship—all inhabitants are New Zealand citizens.Footnote 146
E. Sui Generis Categories
Examining the political status of islands reveals that, despite incredible diversity, a broad framework to understand the constitutional and legal status of island jurisdictions is possible. Nevertheless, several islands do not fit neatly on this scale. This final section explores islands whose distinctive histories leave them unique among island jurisdictions. Three broad factors influencing their unique status can be identified: history, international law and politics.
Three island territories within the British Isles sit within this sui generis category. The Bailiwick of Jersey and the Bailiwick of Guernsey which make up the Channel Islands, and the Isle of Man in the Irish Sea are known as the Crown Dependencies. The Crown Dependencies are akin to ‘miniature states’;Footnote 147 they are not part of the UK but are self-governing possessions of the British Crown. They have their own elected assemblies, administrative, fiscal and legal systems, and are not represented in the British Parliament. The UK Government, however, remains constitutionally responsible for their defence and diplomatic representation. Unlike the BOTs which were formally part of the British Empire, the Crown Dependencies were never colonial possessions but ‘feudatory kingdoms’.Footnote 148 Perhaps consistent with this ancient political status, the constitutional relationship between the Crown Dependencies and the UK is not enshrined in any formal document. Rather, the Crown acting through the Privy Council is responsible for their good government. Given their status as self-governing jurisdictions, UK legislation rarely applies to the Crown Dependencies, and is only extended after consulting the island authorities and obtaining their consent.Footnote 149 This ensures a substantial degree of autonomy. The Isle of Man, for instance, has its own controls on immigration and housing, and relatively low taxes, encouraging a major offshore financial sector that accounts for most of its gross domestic product. Despite this significant autonomy, the Crown Dependencies are not internationally recognised States, but ‘territories for which the United Kingdom is responsible’.Footnote 150
The Norwegian Svalbard archipelago, situated in the High Arctic between 74° and 81° north and between 10° and 35° east, also operates under a unique political and legal status. Rather than an historic feudal possession, however, this status is drawn from a treaty signed in the aftermath of World War I. Originally uninhabited, from the seventeenth century onwards several European States asserted rights to hunt and whale within the archipelago and its surrounding seas. It was not until 1920 that the ‘full and absolute sovereignty of Norway over the Archipelago’ was confirmed.Footnote 151 However, the Svalbard Treaty granted certain rights to the other signatories. Norway's qualified sovereignty over the islands is reflected in a series of rights and entitlements enjoyed by other State parties including: fishing and hunting in the islands and ‘territorial waters’; access and entry for ‘any reason or object whatever’ to the waters, fjords and ports of the islands; and continued recognition of certain rights previously acquired by foreign nationals, including mining rights.Footnote 152 Notwithstanding this unique status, the jurisdiction is an integral unit of the unitary Kingdom of Norway.Footnote 153 The Norwegian Government appoints a Governor to administer the archipelago. The Governor acts as both the chief of police and county governor.
A third category of sui generis island jurisdictions emerges directly from politics rather than history or law. The Republic of China (ROC, or Taiwan) ‘appears to comply in all respects with the criteria for statehood … but is universally agreed not to be a separate state’.Footnote 154 This is a consequence of the complex political relationship between the ROC and the PRC. The ROC is the de facto government of Taiwan, but the PRC asserts that it is the sole legitimate government of all China—including Taiwan. In 1971, the UNGA accepted this position, voting to eject representatives of Taiwan from the UN and admitting the PRC as ‘the only legitimate representative of China to the United Nations’.Footnote 155 However, complications remain. Under its ‘One-China’ policy, the PRC refuses to maintain diplomatic relations with any State that formally recognises Taiwan. Owing to the PRC's political, economic and military strength, many States have broken off formal diplomatic relations with Taiwan over the years. Only 11 States and the Holy See recognise Taiwan, and that number has been slowly decreasing.Footnote 156 Nonetheless, many States that formally recognise the PRC maintain unofficial consular links with Taiwan.
F. Brief Reflections
The constitutional legal status of islands is marked by diversity. But what accounts for the specific approaches adopted? One comprehensive survey found that three factors were significant in explaining whether an island territory obtained an autonomous position within a larger State. For Pär Olausson, geographic separation of at least 1,000 km from the mainland, cultural distinctiveness, and a previous history of self-rule or self-administration were key indicators in determining whether an island exercised autonomy.Footnote 157 The present study largely explores gradations of autonomy rather than the threshold question of whether autonomy exists but is nonetheless consistent with Olausson's findings. It is noted that the political and legal culture of the mainland State is also significant in determining the constitutional status of an island territory. As has been seen, colonial powers have adopted varied approaches to managing the efficacy of governance in island territories according to their own understanding of authority.
International law also plays a role. In some cases, governance arrangements are protected by treaties. More common, however, is the recognition that islanders themselves have the right to determine their political status. While some islands pursued their own independent Statehood (with or without the acquiescence of their former colonial power), most have been content with fine-tuning their political and legal authority within the State. Nonetheless, as has been emphasised, firm rules are difficult to excavate. Although particularly visible in relation to islands subject to political contestation, larger geo-strategic concerns overlay the approaches adopted in all cases.
IV. RECENT DEVELOPMENTS
The authors earlier described this survey as providing a snapshot in time. Two recent developments in 2023 and 2024 reflect that snapshot. The first is the outcome of 2023 negotiations between Australia and Tuvalu which demonstrate the fluidity and diversity of the legal issues raised by islands. The ‘Falepili Union’, announced on the sidelines of the 2023 Pacific Islands Forum, has been described as the most significant development for Australia and a Pacific Island nation for decades.Footnote 158 The Union is a tailored treaty that builds upon the model of ‘Free Association’ discussed above, and develops a distinctive ‘Union’ arrangement founded on three pillars.
First, the Union is based on ‘values of good neighbourliness, care and mutual respect’. While Australia and Tuvalu are Pacific neighbours, they do not share land or maritime boundaries and are some 3,500 km apart. In this respect the use of the term ‘good neighbourliness’ is notable. It has a distinctive meaning in international environmental law where neighbouring States have responsibility for environmental harm, impact and damage that one may cause to the other.Footnote 159 Given that context, the use of the term in this instance would have been intentional.
Second, the Union recognises Tuvalu's particular challenges arising from climate change. Climate cooperation is provided for while recognising that Tuvalu's Statehood and sovereignty will continue, and the desire of Tuvaluans to continue to live in their territory. Direct reference is made to, ‘more recent technological developments [which] provide additional adaptation opportunities’. While no detail is given as to what this may entail, clearly there is the potential for Australia to assist Tuvalu in combatting sea-level rise including by way of land reclamation and artificial island building within its existing maritime zones. Closely aligned with this initiative is the concept of ‘human mobility with dignity’, which envisages a special pathway for Tuvaluans to live, study and work in Australia, including access to education, health and social security.Footnote 160 A special visa category will need to be developed to facilitate this. No mention has been made, for the time being, of a fast track to Australian citizenship.
Third, the Union provides for mechanisms for Australia to come to the aid and assistance of Tuvalu following military aggression, natural disaster or a public health emergency. Tuvalu will also provide Australia with territorial rights of access, presence and overflight. A distinctive aspect of the enhanced security relationship is that Tuvalu will agree with Australia any form of proposed legal or political security or defence-related engagement with another State, effectively giving Australia decision-making power over certain aspects of Tuvalu's foreign affairs.Footnote 161
The second recent development is the Advisory Opinion sought by the Commission of Small Island States (COSIS)Footnote 162 which was delivered in 2024 by ITLOS. COSIS requested an advisory opinion regarding two UNCLOS obligations: (1) the obligation to prevent, reduce and control pollution of the marine environment in relation to the deleterious effects that result or are likely to result from climate change, including through ocean warming and sea-level rise, and ocean acidification, which are caused by anthropogenic greenhouse gas (GHG) emissions into the atmosphere; and (2) the obligation to protect and preserve the marine environment in relation to climate change impacts, including ocean warming and sea-level rise, and ocean acidification.Footnote 163
The unanimous findings of ITLOS in the COSIS Advisory Opinion were that anthropogenic GHG emissions into the atmosphere constitute pollution of the marine environment for the purposes of Article 1(1)(4) of UNCLOS,Footnote 164 that applying a due diligence standard UNCLOS parties have obligations to prevent this source of marine pollution,Footnote 165 that these and related obligations can be found within Part XII of UNCLOS,Footnote 166 and that Article 192 of UNCLOS creates a specific obligation to protect and preserve the marine environment from climate change impacts and ocean acidification. ITLOS was also of the view that Article 203 ‘reinforces the support to developing States, in particular those vulnerable to the adverse effects of climate change’ in providing preferential funding, technical assistance and services from international organisations.Footnote 167 With respect to islands, ITLOS particularly observed that it was ‘conscious of the deleterious effects climate change has on the marine environment and the devastating consequences it has and will continue to have on small island States, considered to be among the most vulnerable to such impacts’.Footnote 168 While the impact of sea-level rise upon maritime boundaries was not directly addressed, ITLOS acknowledged that the science accepted that sea-level rise ‘posed an existential threat for some Small Islands’.Footnote 169 Although it remains important to acknowledge its status as an Advisory Opinion, the ITLOS response to COSIS points to a new legal direction in how UNCLOS obligations will be interpreted with respect to anthropogenic GHGs and pollution of the marine environment, and how these obligations will be assessed with respect to small island States.
V. CONCLUSION
There has always been a fascination with islands, whether they be just offshore or far distant from the coast, including in oceans on the other side of the world. Colonial powers sought to acquire islands as a means of asserting their global influence, with resulting and ongoing legal legacies. International law initially dealt with that phenomenon through consideration of territoriality and associated sovereignty, which in turn focused on maritime entitlements with the development of the law of the sea. In recent decades, State practice under UNCLOS has resulted in, at times, a forensic assessment of the characterisation of islands and associated features such as rocks, as highlighted by the South China Sea Arbitration. The combination of disputed island territoriality and maritime entitlement has made islands a focal point of international attention in East Asia, the South China Sea, and the Atlantic and Indian Oceans. Some distinctive island international law practices have also emerged regarding trade and finance, and environmental protection and management.
Governance of islands has also raised complex constitutional legal questions and three clear lessons can be drawn from this survey. First, the relationship between sub-national islands and mainland States is characterised by an incredible diversity. Not only is there no single approach, but States with multiple islands adopt varied legal and political arrangements that do not necessarily relate to the size of the island's population nor its distance from the metropole. A range of factors, including these but also encompassing history, politics, strategic concerns, and the determination of islanders themselves influence the contours of the relationship. Often the rationale for the division is unclear. Recall that unlike residents of all other insular areas (and indeed the 50 states and federal districts), residents of American Samoa are US nationals but not citizens. Second, while the content and scope of authority and jurisdiction islands exercise are subject to change, it appears that many islands are largely content to seek greater autonomy within States, rather than external self-determination. Nonetheless, there are important exceptions, as unrest in New CaledoniaFootnote 170 and evolving arrangements in Greenland suggest. Finally, as the recently concluded Falepili Union demonstrates, island territories are pursuing a range of innovative strategies to preserve and protect their autonomy.Footnote 171
Securing territory is a critical precondition for autonomy. However, while island land reclamation has a long history, that strategy may not be adequate to address threats posed by sea-level rise. With the ICJ reviewing an Advisory Opinion request and ITLOS now having delivered the COSIS Advisory Opinion, and bodies such as the International Law CommissionFootnote 172 and International Law AssociationFootnote 173 completing studies on climate change, sea-level rise, human mobility and Statehood, a forensic analysis is taking place of issues critical to the future of islands. The remainder of the 2020s will continue to bring some clarity to unresolved legal questions posed by island peoples, which in turn may create a new diplomatic and legal agenda in which existing, new and innovative international and constitutional law solutions will prove critical.
The twenty-first century has witnessed a proliferation of island territorial and maritime disputes before international courts and tribunals, the march of climate change and sea-level rise and its implications for small island States, and calls by islanders for self-determination. A legal, political and diplomatic maelstrom has developed around these issues extending from international courts and tribunals, to the UN, to regional and sub-regional institutions, and bilateral relations. These events demonstrate that islands and islanders are raising some of the most fundamental issues of global political and legal concern. A ‘legal era of islands’ is emerging.
ACKNOWLEDGEMENTS
This article benefited from valuable comments at the 2023 Comparative Constitutional Law Workshop, held at the University of New South Wales Faculty of Law and Justice in Sydney, Australia in November 2023. Thanks to Tracey Robinson, Rosalind Dixon, Elisabeth Perham, Elisa Arcioni, Lynsey Blayden, Joel Colon-Rios, David Kenny, Scott Stephenson, Lael Weis and others for helpful discussion. The authors also thank the anonymous reviewers and editorial team at the International and Comparative Law Quarterly for their insight and preparation of the manuscript.
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