
International law can be viewed as either a tool or a weapon, depending on how it is wielded. On the one hand, the rules of international law outlining the range of legitimate territorial and maritime claims can provide an invaluable toolbox of objective standards for sorting out a way forward in what can often be a complex problem of international relations. On the other, a misinterpretation or partial understanding of the applicable international law can obfuscate the intentions of the rival claimants and further complicate the overall situation. In some ways, a partial understanding of the applicable law might be more harmful than no knowledge at all.

For the unresolved disputes in the South China Sea, one issue worth considering is the potential significance of the new lighthouses that China has constructed on several geographic features within the Spratly Islands. The recent “China’s Lighthouses in the Spratlys” commentary by Lin Ting-Hui of Taiwan is an example of how a misinterpretation or a partial understanding of the applicable law can obfuscate more than it illuminates. This includes both the international law of the sea, as reflected in the United Nations Convention on the Law of the Sea (UNCLOS), and the customary international law relating to sovereignty claims. Below is an attempt to outline the limited legal significance of those new lighthouses, and a strategic risk arising from their construction.

Lighthouses and Maritime Baselines

Lin correctly identifies the law of the sea as one body of international law that applies to some aspects of the unresolved disputes between the South China Sea claimants. To be sure, the proper application of that body of international law can help improve the overall situation. In particular, the UNCLOS rules prescribe how the coastal states may lawfully draw the maritime baselines along their respective coasts and establish their maritime zones from those baselines.

Several of the new lighthouses built by China were constructed on geographic features that were either low-tide elevations or submerged features prior to China’s “reclamation” activities. In Lin’s commentary, he cites Articles 7 and 47 of UNCLOS, to support the proposition that a coastal state may draw straight baselines from a lighthouse that it has constructed on a low-tide elevation. What he might not realize, however, is that these two rules of law have limited (if any) applicability to the Spratly Islands, and that they must be interpreted properly in the context of the entire treaty, as is required by the international law of treaties.

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The general rule for drawing a coastal state’s maritime baselines is found in Article 5 of UNCLOS, which requires a state to use the low-water line along its coast. As an exception to that general rule, Article 7(1) of the treaty provides that a coastal state may draw straight baselines in two limited situations: (1) when the state’s coastline is “deeply indented and cut into” or (2) if there are “a fringe of islands along the coast in its immediate vicinity.”

The International Court of Justice has held that the rules for drawing straight baselines are intended to be used in exceptional situations only “if a number of conditions are met” and those rules must be applied “restrictively.” But China flipped that established paradigm on its head and legislated in 1992 that it would employ that exceptional methodology for all of the baselines on its coast, including those around its claimed island groups. (The United States has diplomatically and operationally challenged those improperly drawn baselines as an excessive maritime claim.) Assuming for the sake of argument that China’s entire coastline warranted the use of straight baselines, Article 16 of UNCLOS would require China to publish all of the coordinates of those baselines. China declared straight baselines along its mainland coast and around the Paracel Islands in 1996, and around the Senkakus in 2012, but has never declared baselines for any of the islands in the Spratlys or published such coordinates.

Article 7(4) of UNCLOS mentions lighthouses. Lin quotes that provision to offer potential legitimacy for China to someday draw straight baselines in the Spratlys from low-tide elevations where it recently constructed lighthouses. However, Article 7 – including paragraph 4 that Lin quotes – applies only if the coastal state first satisfies one of the two exceptional situations specified in Article 7(1). In other words, if the low-tide elevation is not located on a deeply indented coastline or within a fringe of islands along the coast in its immediate vicinity, then the Article 7(4) rule for drawing of straight baselines from lighthouses on low-tide elevations is simply not relevant.


Moreover, Article 7(4) must be read in proper context with the general rules contained in other provisions of UNCLOS that specify the legal status of low-tide elevations and artificial islands. Specifically, Article 13(1) states that a low-tide elevation may be used as the baseline for measuring the breadth of an island’s territorial sea, but only if that low-tide elevation is located within the territorial sea of that island. At the same time, Article 13(2) of the treaty makes it clear that a low-tide elevation “has no territorial sea of its own” if it is located beyond the coastal state’s mainland or islands. That provision makes no exception allowing for territorial sea around a low-tide elevation if a lighthouse is constructed on it. Thus, whether a lighthouse is constructed on a low-tide elevation is not determinative – what matters is the location of the low-tide elevation (i.e., its proximity to an island). In addition, Articles 60(8) and 80 of UNCLOS specify clearly that artificial islands, installations, and structures “do not possess the status of islands” and have “no territorial sea of their own.” Therefore, any attempt to justify a territorial sea by the mere construction of a building on an artificial island would be legally futile – whether that building was a lighthouse, an outhouse, or a skyscraper.

Additionally, Lin also quotes from Article 47 of UNCLOS to support a similar proposition of drawing “archipelagic baselines” from lighthouses constructed on low-tide elevations. But archipelagic baselines may only be drawn by “archipelagic states” (i.e., states constituted “wholly” of islands), such as Indonesia and the Philippines. Lin’s citation to Article 47 is wholly misguided; the treaty does not permit a continental state, such as China or the United States, to draw straight baselines around the outermost points of an offshore archipelago.

Lighthouses and Sovereignty Claims

After discussing the potential effect of UNCLOS on China’s recent construction of lighthouses in the Spratlys, Lin then argues those activities are more likely intended to solidify China’s sovereignty claim versus claims asserted by other claimant states. More specifically, he states that China appears intent on “safeguarding of its territorial sovereignty” and “efforts to strengthen the legal basis of its claim.”

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To support this point, Lin cites a ruling by the International Court of Justice in the 2002 case between Indonesia and Malaysia concerning the sovereignty of the islands of Pulau Ligitan and Pulau Sipidan. Regrettably, he focuses solely on those portions of the Court’s ruling that briefly discussed the specific detail of a claimant state constructing lighthouses. He overlooks another portion of the ruling that identifies and applies a principle of international law that is more fundamental and universal to the adjudication of competing sovereignty claims than the unique instance of constructing lighthouses.

In evaluating the competing sovereignty claims to a land feature, what matters is not only what action a state has taken, but also when it takes that action. The relevant concept in international jurisprudence is known as the “critical date.” Specifically, the Court in the Indonesia/Malaysia case ruled that “it cannot take into consideration acts having taken place after the date on which the dispute between the Parties crystallized unless such acts are a normal continuation of prior acts and are not undertaken for the purpose of improving the legal position of the Party which relies on them.” Under the facts of that case, the Court concluded that Malaysia’s construction of lighthouses on these two small islands was a relevant act demonstrating Malaysia’s effectivités (i.e. continuous exercise of governmental activity) primarily because Indonesia was not disputing Malaysia’s sovereignty of the two islands “at the time when these activities were carried out.” In other words, actions taken by a claimant state after the critical date are legally “meaningless” when it comes to determining which claimant has the superior claim of sovereignty.

For the South China Sea disputes, there is much legal-historical work yet to be done to identify the critical dates relevant to various competing territorial claims. With respect to the Spratlys, history provides many potential candidates for the date or dates. We know that German surveys of the islands in the late 19th century were protested by the Qing dynasty, though the picture with respect to China’s official reaction to the first modern claim to the islands (lodged by the British) is much less clear. The privately made claim of Tomas Cloma in 1956 drew protest from both Taiwan (as the Republic of China) and Vietnam, though official disputes between two or three governments might not be said to have crystallized until Manila took on Cloma’s claim sometime between 1974 and 1978. Military encounters in the Spratlys might be taken as evidence of a “critical date” when all parties became aware of disputed sovereignty: clashes between Vietnam and Beijing over South Johnson Reef in 1988, or reciprocated protests by Manila (over Beijing’s construction on Mischief Reef in 1995) and Beijing (over Philippine presence on Second Thomas Shoal in 1999) might also be candidates for further investigation. More recently, the negotiation of the non-binding China-ASEAN Declaration on the Conduct of Parties to the South China Sea disputes (DoC) in 2002 suggests an implicit recognition of generalized sovereignty disputes.

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All of these legal developments between the claimant states are evidence of a recognized dispute over the maritime space adjacent to the islands and perhaps the underlying territorial disputes. But, despite the need for closer legal-historical investigation, whether the date is 1887, 1956, 1974, 1995, 2002 or somewhere in between, any reasonable observer would acknowledge that those “critical dates” when all rival claimants were aware or should have been aware of the existence of a sovereignty dispute in the Spratly Islands are all clearly at some point in the past.

Therefore, if Lin wants to make a credible case that Beijing’s recent construction of lighthouses is part of a legal strategy to “strengthen the legal basis” of China’s sovereignty claim to the Spratlys, then he would first need to demonstrate that no dispute existed prior to those recent construction activities. That assertion, however, would fly in the face of reality. As one international law expert aptly observed, the sovereignty over the Spratly features is “indisputably disputed.”

A Paramilitary Strategy Cloaked in Legal Rhetoric


As discussed above, Lin’s legal analysis on the significance of China’s new lighthouses in the South China Sea is fundamentally flawed for both the law of the sea and customary law of sovereignty. The cause of this problem might simply be an innocent misunderstanding by an individual who is an expert in international relations, but who is not trained in international law. Regardless, giving him the benefit of the doubt, the potential effect of such flawed legal analysis could be significant: namely, the strategic risk of arming a claimant state, such as China, with legal rhetoric as a weapon to execute a paramilitary strategy in the South China Sea.

If China was to read Article 7(4) of UNCLOS in isolation and out of context, it might finish its “reclamation” activities in the Spratlys and emplacement of lighthouses on those artificial islands, and then attempt to declare belatedly straight baselines from those artificial islands and claim internal waters enclosed therein. But such actions would perpetuate China’s manipulation of the prevailing legal regime for purposes for which it was not intended. More fundamentally, it would facilitate the erosion of an international rule-set which effectively balanced the interests of coastal states and user states.

Similarly, if were China to read the excerpts of the 2002 I.C.J. decision about lighthouses in isolation and ignore the requirement that such actions are legally relevant only before a dispute arises, then it might convince itself and attempt to persuade the international community that such actions bolster its sovereignty claims. But such legal rhetoric would undermine the “critical date” principle of international law, and incentivize tit-for-tat construction activities by other South China Sea claimants and other states elsewhere in the world where there is disputed sovereignty. Such a state of affairs would be both unhelpful in sorting out where sovereignty actually lies, and may also invite conflict as rival claimants rush to demonstrate a “display of power and authority” over the same area.

The specific question about the significance of these new lighthouses uncovers a central paradox to the South China Sea disputes. All claimant states, including China, would like to achieve their national strategic goals by legally defensible means because perceived compliance with internationally-established norms and standards confers tangible strategic benefits. For that reason, Beijing (and to some extent, the other claimant states) pursue questionable claims through recourse to legal rhetoric.

Seen in this context, intentionally or not, quasi-legal commentary runs the risk of misrepresenting the law and encouraging the claimants to pursue what need to be understood as purely strategic goals. By contrast, thoughtful strategic commentary that maintains an open dialogue without misrepresenting the legal realities at play is an essential first step to keeping China and the other South China Sea claimants honest in what is already a turbulent sea.

Commander Jonathan G. Odom and Kerry Lynn Nankivell are both professors at the Daniel K. Inouye Asia-Pacific Center for Security Studies in Honolulu, Hawaii, where Commander Odom teaches international law and Professor Nankivell teaches maritime security. The views expressed are their own and do not necessarily reflect the positions of the U.S. Department of Defense or any of its components.