G.R. No. 187167 ; August 16, 2011
PROF. MERLIN M. MAGALLONA, ET AL., Petitioners, vs. HON. EDUARDO ERMITA, IN HIS CAPACITY AS EXECUTIVE SECRETARY, ET AL., Respondents.

FACTS

Petitioners, consisting of professors of law, law students, and a legislator, filed an original action for certiorari and prohibition assailing the constitutionality of Republic Act No. 9522 (RA 9522). RA 9522 amended Republic Act No. 3046 to adjust the country’s archipelagic baselines to comply with the United Nations Convention on the Law of the Sea (UNCLOS III), which the Philippines ratified. The law classified the Kalayaan Island Group (KIG) and Scarborough Shoal as “regimes of islands” under UNCLOS III. Petitioners argued that RA 9522 was unconstitutional because: (1) it reduced Philippine maritime territory, violating the constitutional definition of national territory based on the Treaty of Paris and related treaties; and (2) it opened waters landward of the baselines to maritime passage, undermining sovereignty, security, the nuclear-free policy, and marine resources. Respondents raised preliminary issues regarding petitioners’ locus standi and the propriety of the writs, and defended RA 9522 as necessary compliance with UNCLOS III that did not relinquish any territorial claims.

ISSUE

1. Preliminarily: (a) Whether petitioners possess locus standi; and (b) Whether the writs of certiorari and prohibition are proper remedies.
2. On the merits, whether RA 9522 is unconstitutional.

RULING

1. On the preliminary issues: (a) Petitioners possess locus standi as citizens, as the case raises issues of national significance requiring resolution, and it is difficult to find other litigants with a more direct interest. Their claims of standing as legislators and taxpayers were undermined as the petition alleged no infringement of legislative prerogative or misuse of public funds. (b) The writs of certiorari and prohibition are proper remedies to test the constitutionality of statutes when the Court exercises its power of judicial review, especially for laws of profound national importance.
2. On the merits, RA 9522 is NOT unconstitutional. The Court held that:
– RA 9522 is a statutory tool to demarcate the country’s maritime zones and continental shelf under UNCLOS III, not to delineate Philippine territory. UNCLOS III is a multilateral treaty regulating sea-use rights over maritime zones and does not govern the acquisition or loss of territory. The baselines law is a mechanism for the State to mark its maritime zones under international law.
– The constitutional definition of national territory, based on the Treaty of Paris and other treaties, is not violated. The Treaty of Paris and related treaties are treaties of cession that defined the boundaries of the archipelago surrendered by Spain to the United States. These treaties did not bind third-party States like the Netherlands or the United Kingdom regarding their own territories. The specification of geographic coordinates in these treaties served to delimit the archipelago, not to claim all waters within the rectangular boundaries as territorial waters. The Philippines’ territory under international law is limited to the islands and waters within the archipelago, not the entire rectangular area.
– RA 9522 does not abandon the Philippines’ claim over the KIG or Scarborough Shoal. By classifying them as “regimes of islands” under UNCLOS III, the law allows them to generate their own maritime zones, consistent with the Philippines’ claim of sovereignty. This classification is a strategic acknowledgment of sovereignty under the UNCLOS III framework. The law’s silence on the Sabah claim does not imply abandonment, as statutes do not ordinarily deal with claims to foreign territory.
– RA 9522 does not undermine national security, the nuclear-free policy, or marine resources. The law does not open internal waters to foreign vessels; archipelagic waters remain subject to the Philippines’ sovereignty. UNCLOS III itself provides for the right of innocent passage and archipelagic sea lanes passage, which are not absolute and are subject to the Philippines’ regulatory power. The constitutional policy against nuclear weapons is not violated by mere passage, and environmental protections under UNCLOS III and domestic laws remain applicable.
– The passage of RA 9522 was necessary to comply with UNCLOS III deadlines (e.g., for extended continental shelf claims) and to optimize the location of basepoints, ensuring the Philippines could claim the maximum maritime entitlements under international law.