FACTS: This is an original action for Prohibition to declare unconstitutional Republic Act No. 9591 (RA 9591), creating a legislative district for the city of Malolos, Bulacan, for violating the minimum population requirement for the creation of a legislative district in a city. On 1 May 2009, RA 9591 lapsed into law, amending Malolos City Charter,2 by creating a separate legislative district for the city. The population of Malolos City was 223,069. The population of Malolos City on 1 May 2009 is a contested fact but there is no dispute that House Bill No. 3693 relied on an undated certification issued by a Regional Director of the National Statistics Office (NSO) that “the projected population of the Municipality of Malolos will be 254,030 by the year 2010 using the population growth rate of 3.78 between 1995 to 2000.”
ISSUE: RA 9591 is unconstitutional for failing to meet the minimum population threshold of 250,000 for a city to merit representation in Congress as provided under Section 5(3), Article VI of the 1987 Constitution and Section 3 of the Ordinance .
RATIO DECIDENDI: RA 9591 is unconstitutional for being violative of Section 5(3), Article VI of the 1987 Constitution and Section 3 of the Ordinance appended to the 1987 Constitution. The 1987 Constitution requires that for a city to have a legislative district, the city must have “a population of at least two hundred fifty thousand.” House Bill No. 3693 cites the undated Certification of Regional Director Alberto N. Miranda of Region III of the National Statistics Office (NSO) as authority that the population of the City of Malolos “will be 254,030 by the year 2010.” The Certification states that the population of “Malolos, Bulacan as of May 1, 2000 is 175,291.” The Certification further states that it was “issued upon the request of Mayor Danilo A. Domingo of the City of Malolos in connection with the proposed creation of Malolos City as a lone congressional district of the Province of Bulacan.” First, certifications on demographic projections can be issued only if such projections are declared official by the National Statistics Coordination Board (NSCB). Second, certifications based on demographic projections can be issued only by the NSO Administrator or his designated certifying officer. Third, intercensal population projections must be as of the middle of every year. Moreover, the Certification states that “the total population of Malolos, Bulacan as of May 1, 2000 is 175,291.” The Certification also states that the population growth rate of Malolos is 3.78% per year between 1995 and 2000. Based on a growth rate of 3.78% per year, the population of Malolos of 175,291 in 2000 will grow to only 241,550 in 2010. Any population projection forming the basis for the creation of a legislative district must be based on an official and credible source. That is why the OSG cited Executive Order No. 135, otherwise the population projection would be unreliable or speculative.