G.R. No. 145993 - People vs. Mallari

On November 20, 2001, the Sangguniang Panlungsod of Manila enacted Ordinance No. 8027, reclassifying certain portions of land in Pandacan and Sta. Ana from Industrial II to Commercial I.
The ordinance was approved by Mayor Jose L. Atienza, Jr. on November 28, 2001, and became effective on December 28, 2001, after its publication.
The ordinance was promulgated pursuant to the police power of local government units to promote urban planning, health, public safety, and general welfare.
Section 1 of the ordinance specified the reclassification and Section 3 required owners or operators of businesses disallowed by the ordinance to cease operations within six months of its effectivity.
Among the businesses affected were the Pandacan Terminals operated by Caltex (Philippines), Inc., Petron Corporation, and Pilipinas Shell Petroleum Corporation.

On June 26, 2002, the City of Manila and the Department of Energy (DOE) entered into a Memorandum of Understanding (MOU) with the three oil companies.
The MOU agreed on a scale-down program of the Pandacan Terminals, including removal of certain tanks, creating safety buffer and green zones, and establishing joint operations within limited areas.
The City of Manila and DOE committed to endorse the MOU to the City Council for action, support continuous operation of the oil companies within legal limits, monitor compliance, and protect the safety buffer zones from illegal occupation.
The Sangguniang Panlungsod ratified the MOU in Resolution No. 97, setting a validity period of six months starting July 25, 2002.
On January 30, 2003, Resolution No. 13 extended the MOU's effectivity to April 30, 2003 and authorized Mayor Atienza to issue special business permits to the oil companies, while calling for reassessment of the ordinance.

Petitioners Social Justice Society (SJS), Vladimir Alarique T. Cabigao, and Bonifacio S. Tumbokon filed an original petition for mandamus on December 4, 2002.
They sought to compel Mayor Atienza to enforce Ordinance No. 8027 and order the immediate removal of the Pandacan Terminals.
Petitioners argued that the mayor had a mandatory legal duty under Section 455 (b)(2) of the Local Government Code to enforce the ordinance, which he has neglected.
The mayor contended that the ordinance had been superseded by the MOU and the resolutions but also claimed the ordinance remained valid and that the MOU served only as a guideline.
There were pending annulment cases filed by the oil companies questioning the validity of Ordinance No. 8027.

Whether Mayor Atienza has a mandatory legal duty to enforce Ordinance No. 8027 and order the removal of the Pandacan Terminals.
Whether the June 26, 2002 Memorandum of Understanding (MOU) and the Sangguniang Panlungsod’s Resolutions No. 97 (2002) and No. 13 (2003) can amend or repeal Ordinance No. 8027.