Section 10, Article X of the 1987 Constitution states that “(n)o province, city, municipality, or barangay shall be created, divided, merged, abolished, or its boundary substantially altered, except in accordance with the criteria established in the local government code and subject to approval by a majority of the votes cast in a plebiscite in the political units directly affected.”
Applying this provision, the Supreme Court, in the case of League of Cities of the Philippines (LCP), et al. vs. Commission on Elections, et al. (G.R. No. 176951, G.R. No. 177499 & G.R. No. 178056; 24 August 2010), held that the creation of local government units must follow the criteria established in the Local Government Code and not in any other law. The High Court stressed that Congress could not write such criteria in any other law, like laws creating cities or converting municipalities into cities. The clear intent of the Constitution, said the High Court, was to insure that the creation of cities and other political units follow the same uniform, non-discriminatory criteria found solely in the Local Government Code. Consequently, when Congress enacted cityhood laws which exempted 16 municipalities from the increased income requirement under the Local Government Code, as amended by Republic Act No. 9009 (RA 900), the exemption was held to be in violation of Section 10, Article X of the 1987 Constitution. That the 16 municipalities had pending cityhood bills in Congress before the income requirement was increased was of no moment. To be valid, said the High Court, such exemption must be written in the Local Government Code and not in any other law, including the cityhood laws.
To know more about said case, click on Digested Cases under Tools.