Introduction: International law and the South China Sea
After a long summer replete with tensions and incidents in both the South China  and East China Seas, the new year failed to bring renewed hopes for a peaceful resolution to the myriad territorial conflicts casting a shadow on the Asia-Pacific Region. Rather the contrary, renewed incidents, naval rearmament, claims and counterclaims, not always veiled threats to resort to force, and decentralized boycott campaigns and cyberspace clashes. One novelty was the decision by the Philippines to try a new tack in its clash with China, resorting to a tool not previously employed by any of the claimants,  namely a request for arbitration under UNCLOS (the United Nations Convention on the Law of the Sea).
Although this gambit was rejected by China, and the fate of the case is uncertain at the time of writing, we will examine the legal positions of Manila and Beijing in the context of their wider dispute, and the far-reaching implications of the case. 
The request had to take into account China's decision to opt out of UNCLOS arbitration on certain issues pertaining to their conflict, above all the exact delimitation of maritime borders. Although the Philippines' arbitration request did not thus refer to maritime boundaries per se, it is still not completely clear whether the International Tribunal of the Law of the Sea (ITLOS) will accept the case.
An arbitration tribunal, made up of five judges, has been convened but has not yet ruled on whether it has jurisdiction. Of particular interest in light of the ongoing China-Japan territorial conflict over the Diaoyutai/Senkakus islands is the fact that ITLOS is headed by a Japanese judge. Although not a party to the South China Sea dispute, Tokyo has provided a measure of support on maritime issues to Manila and Hanoi in recent years.
Some see the case as a test of whether international law and tribunals such as ITLOS can contribute to peaceful resolution of outstanding territorial disputes in Asia in a time of profound transformation. It is particularly relevant in view of the disparity in size and military potential between the Philippines and China, although the former is supported by other powers.
What is Manila asking for? Bypassing China's derogation
On 22 January, 2013, the Philippine government informed the Chinese Embassy in Manila that it had submitted an application for arbitration in accordance with UNCLOS.  This was rejected by Beijing, whose ambassador to Manila, Ma Keqing, delivered a note verbale on 19 February "stating that China rejects and returns the Philippines' Notification and Statement of Claim". 
The first thing to understand about the case is that UNCLOS provides for compulsory arbitration of certain disputes, but it also allows signatories to avoid arbitration by declaring a derogation in certain exceptional cases, that is a decision to opt out of arbitration. China did so, and the Philippines was thus forced to tread carefully when drafting its request, to prevent Beijing from resorting to these exceptions, which include the delimitation of maritime borders and military activities.
The success of the Filipino case crucially depends on the ability to convince ITLOS that Manila is not seeking a ruling on any question on which UNCLOS allows Beijing to opt out of arbitration and indeed for which China did so. On the other hand, should China later decide to contest the proceedings, her first line of defense would be precisely that an arbitration tribunal lacks the power to issue a ruling on a matter covered by China's derogation.
The above is clear from the wording of Manila's submission, and the accompanying note addressed to the Chinese Embassy, whose first lines state that what the Philippines seeks is to "clearly establish the sovereign rights and jurisdiction of the Philippines over its maritime entitlements in the West Philippine Sea", without any mention of specific maritime borders.  In the application itself, Manila refers to the extent of China's exclusive economic zone (EEZ), but does not dispute any specific line or territorial claims.
Rather, it notes how disproportionate and disconnected from the Law of the Sea Chinese claims are. In Introduction 1, the text says that the Philippines "challenge China's claims to areas of the South China Sea and the underlying seabed as far as 870 nautical miles from the nearest Chinese coast''. 
Next, in Introduction 2, Manila opens fire on one of the pillars of Beijing's claims to most of the South China Sea, namely the so called "nine-dash line" defining the territory over which it demands "sovereignty" and "sovereign rights". In addition, in Introduction 3, the text states that within the "nine-dash line" China has "laid claim to, occupied and built structures on certain submerged banks, reefs and low tide elevations that do not qualify as islands under the Convention, but are part of the Philippines' continental shelf, or the international seabed", adding in Introduction 5 that, "in June 2012" the "Province of Hainan" set up a "new administrative unit" covering "all of the maritime features and waters within the 'nine dash line''' and later passed a law, which went into force "on 1 January 2013'', providing for the "inspection, expulsion or detention of vessels 'illegally' entering the waters claimed by China within this area''. 
China's territorial claims in the South China Sea
This is followed later in the Introduction by a straight demand for an award that, among others, "declares that the Parties' respective rights and obligations in regard to the waters, seabed and maritime features of the South China Sea are governed by UNCLOS, and that China's claims based on its 'nine dash line' are inconsistent with the Convention and therefore invalid." 
Furthermore, in Introduction 7, Manila stresses that "The Philippines does not seek in this arbitration a determination of which party enjoys sovereignty over the islands claimed by both of them. Nor does it request a delimitation of any maritime boundaries. The Philippines is conscious of China's Declaration of 25 August 2006 under Article 298 of UNCLOS, and has avoided raising subjects or making claims that China has, by virtue of that Declaration, excluded itself from arbitral jurisdiction." 
Actually, the submission itself devotes section 40 to preemptively attack Beijing's reliance on the 25 August 2006 declaration, stating that "the Philippines' claims do not fall within" it "because they do not: concern the interpretation or application of Articles 15, 74 and 83 relating to sea boundary delimitations; involve historic bays or titles within the meaning of the relevant provisions of the Convention; concern military activities or law enforcement activities; or concern matters over which the Security Council is exercising functions assigned to it by the UN Charter''. 
It is thus clear that the "core" (a term employed by the Department of Foreign Affairs itself, ) of Manila's case is a demand for a declaration that China's "nine dash line"  is not in accordance with UNCLOS. This refers to the concept of the "nine dash line" itself, and to the construction of facilities and declaration of territorial seas / EEZ around islets not considered islands under UNCLOS, which Manila claims are either inside her EEZ or in the high seas (without seeking, as already explained, a delimitation of either, or of China's own EEZ). 
Thus, the gist of the submission is two-fold: to seek to exclude the concept of a "nine-dash line" from the law of the sea, as not falling into any of the categories (such as territorial sea or EEZ) recognized by UNCLOS and by the customary law of the sea (which to a large extent UNCLOS codifies), and to try to prevent Beijing's de facto control of submerged features and islets (and the erection of artificial structures on them) from giving rise to accepted claims to territorial seas and EEZs.
This dual response corresponds to Beijing's two-pronged strategy, namely trying to impose a new legal concept and, should that fail, relying on a combination of physical control over islets and existing legal categories (territorial sea and EEZ) to achieve the same purpose.
In China's case, though, achieving her ultimate target through this fallback strategy would also require forcing a reinterpretation of the concept of an EEZ so that the rights of coastal states were expanded, including first and foremost the exclusion of military and intelligence-gathering activities by other countries.
The submission refers to these submerged features when it states that "Even before its first official espousal of the 'nine dash line' China began to seize physical control of a number of submerged features and protruding rocks ... and to construct artificial 'islands' on top of them", adding that they include "Mischief Reef, McKennan Reef, Gaven Reef and Subi Reef" and that none of them "is an island under Article 121 of UNCLOS" but "at best low tide elevations, far removed from China's territorial sea, exclusive economic zone and continental shelf".
The text also argues that "Because they are not above water at high tide, they are part of another State's continental shelf, or the international seabed" and claims that China acted "unlawfully" by seizing them and declaring "maritime zones around them." 
The text furthermore refers to "six small rocks that protrude above sea level within the Philippines' exclusive economic zone", namely "Scarborough Shoal", which China "seized" in 2012, claiming "a maritime zone for itself" extending to "approximately 70 M to the East", in accordance with the "nine dash line." 
It is important to note that the submission explains that both China and the Philippines "assert sovereignty" over Scarborough Shoal but does not ask for a ruling on this matter. Instead, it stresses that, disregarding who should exercise sovereignty, "None of the rocks, which lie in close proximity to one another, generates entitlement to more than a 12 M territorial sea."  Once more, Manila seeks to bypass questions on the territorial extent of sovereignty, concentrating instead on its consequences according to UNCLOS.
Whatever the merits of the Filipino case, no one, and certainly not Manila or ITLOS, can force Beijing to participate in the proceedings, make submissions, designate an arbitrator, and agree on the other three judges. However, there are two things that Manila can do. First of all, it could hope to get ITLOS to issue a ruling with Beijing absent. If the tribunal refused to do so, then it could at least try to portray China in a bad light, as a country not fully sure of the merits of its own case and reliant on might rather than right.
This was explained in some detail by Romel R Bagares,  an international law professor at Lyceum Philippines University College of Law, who wrote that "unless the parties agreed to the contrary, the default mode for question of interpretation and application of the UNCLOS or relevant treaties is an arbitration under ANNEX VII", but in signing up to UNCLOS, states can "opt out of these compulsory procedures under the so-called Article 298 exceptions, which, among other things, pertain to disputes concerning military activities, including military activities by government vessels and aircraft engaged in non-commercial service, and disputes concerning law enforcement activities in regard to the exercise of sovereign rights or jurisdiction as well as sea boundary delimitations, or those involving historic bays or titles".
Bagares also explained that China had done so "in a formal declaration on August 25, 2006".
For these reasons, as discussed above, the Philippines was extremely careful when drafting its request for arbitration, in a bid to bypass this Chinese derogation. Manila wanted to make clear that its request covered only areas not included in Beijing's reservation, made under Art. 298 of UNCLOS, and that it was not asking for a ruling on those other areas.
This was also explained by another Filipino law professor, Dr Harry Roque,  who noted that, "Our submission of claims is crafted in a manner that will exclude all of China's reservations. For instance, the submission asked the tribunal to rule on the validity of the controversial 'nine-dash line', since it does not constitute either China's internal waters, territorial sea, or exclusive economic zone. This asks the tribunal to rule, as an issue of interpretation of UNCLOS, whether the nine-dash lines complies with the Convention. Likewise, China has built permanent structures on reefs such as Mischief and Subi, which are permanently under water. The submission asks that the tribunal declare that since these are neither "rocks" nor "islands'', they should be declared as forming part of our country's continental shelf, or the natural prolongation of our land mass".
China says "No". Is a ruling still possible?
As expected, China refused to submit to arbitration. It was no surprise on two accounts: Beijing's traditional hostility to international arbitration or submission to any kind of tribunal,  and the repeated warnings over the previous few months to Manila not to initiate such proceedings. On receiving China's response, the Philippines stated that, "China's action will not interfere with the process of Arbitration initiated by the Philippines on 22 January 2013. The Arbitration will proceed under Annex VII of UNCLOS and the 5-member arbitration panel will be formed with or without China." 
This begs the question of whether China's refusal is in itself in accordance with international law. The starting point must be the twin concepts of sovereignty and consent. The pillar of international law, sovereignty, basically means that states do not recognize any superior. Although qualified by concepts such as collective security, this remains very much the foundation of international law and the international system. From this comes the fact that states are only bound by those rules and decisions to which they consent. In the case of customary international law, it is the practice of states plus their belief in its compulsory nature, which provides the necessary consent. In the case of treaties, consent is provided through signature and ratification of conventions. Concerning arbitration, parties must voluntarily submit to the proceedings.
Has then China provided her consent? With regard to the applicable law, UNCLOS, we have noted that Beijing is a signatory, albeit with some reservations provided for in the text of the Convention itself. Therefore, with those exceptions, there is indeed consent as to the material aspects of the dispute.
Concerning arbitration, Beijing has rejected it. Or has she? It is true that, even before Manila filed suit, China had made clear that it would not accept arbitration. However, in international law (just as in domestic law) there are two ways to consent to arbitration. First, the parties to a dispute may agree to it once the dispute emerges and they are unable to reach a solution through other means. Second, they may agree in advance of any such dispute. This is what the Philippines believes China did when ratifying UNCLOS, as explained in the submission, which claims that since "The Philippines and China are both parties to UNCLOS ... it follows that both parties have given their advance consent to the regime of settlement of disputes concerning the interpretation and application of the Convention established in part XV." 
This is a view that Beijing has not squarely addressed. As we shall see later, China has rather resorted to insisting on its preference for bilateral negotiations and its interpretation of the 2000 Declaration on the Conduct of Parties in the South China Sea (DOC). However, China has not put forward any explanation as to how its advance consent contained in joining UNCLOS would not apply to it.
Thus, as provided for in Art. 3(b) of ANNEX VII UNCLOS, Manila appointed an arbitrator, Judge Rudiger Wolfrum,   and expected Beijing to do likewise, with three others to be chosen by agreement between the parties. However, on 31 January, a spokesman for China's Foreign Ministry, Hong Lei, announced that Beijing had rejected Manila's request for international arbitration, adding that it was contrary to the "ASEAN consensus for bilateral negotiations", a reference to the 2000 Declaration on the Conduct of Parties in the South China Sea (DOC). 
With regard to the 2000 Declaration, however, Professor Bagares believes that it "actually allows resort to UNCLOS mechanisms, as is stated for instance in DOC principles 1, 3 and 4." 
Going beyond the impact of the ASEAN Declaration, the question that immediately emerged, following Beijing's formal refusal to take part in arbitration proceedings, was whether the case could move forward and an arbitration tribunal be convened anyway. The possibility that a party refuses to take part in a case is actually considered in the Convention itself, with Article 9 of Annex VII (Arbitration) UNCLOS reading:
If one of the parties to the dispute does not appear before the arbitral tribunal or fails to defend its case, the other party may request the tribunal to continue the proceedings and to make its award ... Before making its award, the arbitral tribunal must satisfy itself not only that it has jurisdiction over the dispute but also that the claim is well founded in fact and law. 
That is, the Philippines could ask ITLOS to move forward, rule that it has jurisdiction over the case, and appoint the members of the ad hoc arbitration tribunal that will hear it. This would not, of course, assure that the tribunal would rule in accordance with the Filipino demands, since its members would have to ascertain the facts and applicable law, even without the benefit of Chinese submissions. Courtesy Joyo News, from Asia News