G.R. No. L-31812 March 17, 1978
JUAN COJUANGCO, petitioner, vs. Hon PIO R. MARCOS, in his capacity as Judge of the Court of First Instance of Baguio, and ENRIQUE J. L. RUIZ, respondents.

FACTS

Petitioner Juan Cojuangco purchased Lot 19 from the Bureau of Lands. After a resurvey, the lot was found to contain an excess area of 179 square meters. Respondent Enrique J. L. Ruiz, owner of the adjacent lot, constructed a retaining wall and driveway encroaching upon a portion of Cojuangco’s lot. Cojuangco sued Ruiz for recovery and damages. The trial court, in a 1959 decision affirmed by the Court of Appeals, ruled Ruiz was a builder in bad faith, ordering him to demolish the encroaching wall and pay rentals and attorney’s fees. The Supreme Court denied Ruiz’s petition for review, making the judgment final.
During the pendency of the appeal, Cojuangco secured a patent and title for a reduced area of his lot (Lot 19-A), expressly without prejudice to his claim over the contested encroached portion (Lot 19-C). Years later, to execute the final judgment, Cojuangco moved for an alias writ. Respondent Judge Pio R. Marcos, however, granted Ruiz’s ex parte motion and issued orders in 1969 setting aside the writ and effectively nullifying the 1959 judgment. The lower court reasoned that a resurvey plan indicated the contested area was public land, not part of Cojuangco’s titled property.

ISSUE

Whether the respondent judge committed grave abuse of discretion in refusing to execute a final and executory judgment.

RULING

Yes. The Supreme Court granted the petition for mandamus, set aside the lower court’s orders, and directed the issuance of an alias writ of execution. The legal logic is clear: a final and executory judgment becomes the law of the case between the parties and must be enforced mandatorily. The lower court’s jurisdiction was limited to executing the judgment, not to re-examining or reversing it. Its action constituted a grave abuse of discretion.
The Court held that Lot 19-C, though excluded from Cojuangco’s later-issued title, was no longer public land. Cojuangco had a vested right to it arising from his duly approved sales application and the 1952 order of the Director of Lands for the issuance of a patent, which is tantamount to the patent itself. The issuance of the title for the reduced area was without prejudice to this claim. Therefore, the lower court’s premise that the area was public land was erroneous. Its duty to execute the final judgment, which conclusively determined Cojuangco’s ownership and Ruiz’s obligation to demolish and pay, was purely ministerial. Mandamus lies to compel the performance of this duty. Due to Ruiz’s tactics frustrating execution, the Court also ordered him to pay Cojuangco attorney’s fees.