G.R. No. 237428, May 11, 2018
Republic of the Philippines, represented by Solicitor General Jose C. Calida, Petitioner vs. Maria Lourdes P.A. Sereno, Respondent

FACTS

The Republic, through the Solicitor General, filed a Petition for Quo Warranto against Chief Justice Maria Lourdes Sereno. The petition alleged that Sereno, during her prior employment as a professor at the University of the Philippines College of Law and as a government legal counsel, failed to regularly file her Statements of Assets, Liabilities and Net Worth (SALNs) as required by law. The Republic argued that these repeated failures to file constituted a violation of the Constitution, the Anti-Graft Law, and the Code of Conduct and Ethical Standards for Public Officials and Employees.
The core contention was that these omissions demonstrated a lack of the “proven integrity” required by the Constitution for appointment to the Judiciary. The Republic asserted that the Judicial and Bar Council (JBC) would have been precluded from considering her nomination had these deficiencies been known, thereby rendering her appointment as Chief Justice null and void from the beginning. Sereno countered, questioning the propriety of the quo warranto proceeding against an impeachable officer and asserting substantial compliance with SALN requirements.

ISSUE

The primary issue was whether a quo warranto petition is a proper remedy to challenge the validity of the appointment of a sitting Chief Justice on the ground of lack of eligibility due to failure to meet the constitutional requirement of “proven integrity.”

RULING

The Supreme Court, by a vote of 8-6, granted the petition and ousted Chief Justice Sereno. The Court held that quo warranto was a proper remedy. It ruled that the one-year prescriptive period for filing a quo warranto petition under Rule 66 of the Rules of Court did not apply because the State is never estopped by the mistakes of its agents, and the government can assail an invalid appointment at any time. The Court emphasized that the requirement of “proven integrity” is a continuing eligibility requirement.
On the merits, the Court found that Sereno’s failure to file multiple SALNs during her government service was a clear violation of the law. This failure was not a mere formal defect but a deliberate omission that betrayed a lack of the honesty and probity integral to “proven integrity.” The Court concluded that these omissions were so fundamental that they disqualified her from the outset. Since the JBC, in processing her application, relied on her incomplete submission which excluded these missing SALNs, it was deprived of the full basis to assess her integrity. Consequently, her appointment was declared invalid ab initio for lack of the constitutional qualification.