Population Projections and Legislative Districts: The Malolos Case on Constitutional Compliance

The Supreme Court's 2010 decision in Aldaba v. Commission on Elections (G.R. No. 188078) serves as a crucial reminder that constitutional requirements cannot be bypassed through unreliable data. The Court struck down Republic Act No. 9591, which sought to create a separate legislative district for Malolos City in Bulacan, because the law relied on a defective population projection that failed to meet the constitutional threshold of 250,000 inhabitants.

The Facts

Before May 2009, Bulacan had four legislative districts, with Malolos City forming part of the First District along with several municipalities. In 2007, lawmakers filed bills seeking to create a separate district for Malolos City. The legislative record cited a certification from a Regional Director of the National Statistics Office (NSO) projecting that Malolos' population "will be 254,030 by the year 2010."

Petitioners—taxpayers and residents of Malolos City—challenged the law's constitutionality, arguing that it violated the minimum population requirement for city legislative districts under Section 5(3), Article VI of the 1987 Constitution and Section 3 of the Ordinance appended to the Constitution.

The Issue

The central question was whether Malolos City had a population of at least 250,000—whether actual or projected—to justify the creation of its own legislative district in time for the May 2010 elections.

The Ruling

The Supreme Court granted the petition and declared RA 9591 unconstitutional. The Court found that the NSO Regional Director's certification was legally defective on several grounds.

First, the certification violated Executive Order No. 135, which governs the issuance of population certifications. Under these guidelines, demographic projections must first be declared official by the National Statistics Coordination Board (NSCB). The certification in question did not state that the projections had been so declared.

Second, certifications based on projections must be issued by the NSO Administrator or a designated certifying officer. There was no showing that the Regional Director had been designated for this purpose.

Third, the certification violated the requirement that intercensal population estimates be "as of the middle of every year." The certification instead projected a population for the entire year 2010.

The Court also demonstrated that the projection was internally inconsistent. Using the certification's own growth rate of 3.78% per year, Malolos' population of 175,291 in 2000 would grow to only about 241,550 by 2010—well below the 250,000 threshold. Even using the 2007 census figure of 223,069, the population would reach only about 248,365 by August 2010.

Justiciability of Constitutional Compliance

The Court rejected the Office of the Solicitor General's argument that Congress' choice of methods to comply with the population requirement was a non-justiciable political question. The Court emphasized that questions involving compliance with constitutional standards are fundamentally justiciable, falling within the judiciary's checking function under the Constitution.

The Court further explained that under Section 3 of the Ordinance appended to the 1987 Constitution, a city whose population increases to more than 250,000 becomes entitled to a legislative district only in the "immediately following election" after attaining that population. Since Malolos had not attained—and would not attain—the required population before the May 2010 elections, the law could not stand.

Practical Takeaways

• Constitutional thresholds are strict. A city must have a population of at least 250,000 before it can claim a separate legislative district. Projections cannot substitute for actual attainment of the threshold.
• Official data matters. Population certifications must comply with Executive Order No. 135: projections must be declared official by the NSCB, issued by the NSO Administrator or a designated officer, and made as of the middle of the year.
• Legislative findings are reviewable. Courts can and will examine whether Congress complied with constitutional standards in creating legislative districts, even if the issue touches on legislative judgment.
• Timing is critical. A city becomes entitled to a district only in the election immediately following its attainment of the 250,000 population mark—not before.
• Defective data invalidates the law. A law based on unreliable or internally inconsistent population data will be struck down for violating the Constitution.

This article is general information and not legal advice. For your specific situation, consult a lawyer or ask ASG Legal AI.