Former Supreme Court justices and law deans on Thursday questioned the consistency and long-term impact of the Supreme Court’s rulings on the impeachment of Vice President Sara Duterte, warning that its recent decisions could reshape impeachment as a tool for public accountability.
Speaking at a forum at the University of the Philippines Diliman, retired senior associate justice Antonio Carpio said the Court’s January 28, 2026 resolution — which upheld its earlier declaration that the articles of impeachment against Duterte were unconstitutional — was inconsistent with its July 25, 2025 decision.
He noted that while he disagrees with the SC ruling, it is now binding and affects pending impeachment complaints, of which four have been filed against Duterte with Congress this year.
“First, the serious constitutional infirmity in the July 25, 2025 decision was this, the Court said for the transmittal of the impeachment complaint to the Senate, there must be a plenary vote and there was no plenary vote so that is a serious constitutional infirmity… In this resolution of January 28, 2026, the Court said there was a plenary vote, just like that, it did not explain their factual error,” Carpio said.
“That serious constitutional infirmity never happened because the Court walked back its finding that there was no plenary vote,” he added.
Carpio also criticized the additional requirements the Court had imposed on the second mode of impeachment — the endorsement by one-third of House members — including what he described as an administrative hearing at the plenary level.
He said the January resolution effectively restored the procedure that existed before the July 2025 ruling.
“Even now in this present resolution, the Court said there was no violation of the Constitution, so it is really ‘chopsuey.’ I mean, mismatch,” he said.
Carpio argued that Congress acted in good faith, following prevailing jurisprudence at the time.
He also questioned the Court’s new interpretation of “session days,” which it defined as calendar days when plenary sessions are held.
“So, this concept of session day as a calendar day where there are plenary sessions was never a legal concept before January 28, 2026 — not in the US. No court ever said that. No legislature ever adopted that rule. In the Philippines, no court ever said that. No legislature ever adopted that rule. So, it’s a totally new concept,” Carpio said.
While he disagrees with the ruling, the ex-justice said it is now binding and affects pending impeachment complaints “because counting is now based on calendar days.”
Retired justice and 1986 Constitutional Commission member Adolfo Azcuna said the Court effectively corrected a “very fatal error” in its earlier ruling without explicitly admitting it.
“The error was a very fatal error… Instead of saying that ‘we were wrong,’ they just restated the facts, saying there was a plenary vote,” Azcuna said.
Azcuna also objected to the Court’s issuance of procedural guidelines on impeachment.
“Being themselves impeachable, they (justices) cannot be the ones to write the rules for their own impeachment. That would be a violation of due process and violation of fairness. So, for them to make guidelines on the procedure for impeachment is, I think, beyond the scope of their powers because precisely they are impeachable officials,” he said.
He further clarified the constitutional phrase: “No impeachment proceeding shall be initiated against the same official more than once within a period of one year. It does not say ‘more than one (case or proceeding).’”
Azcuna said oral arguments would have helped clarify the issues.
For her part, Gwen Grecia De Vera, dean of the UP College of Law, said aspects of the Court’s handling of the case were “problematic” and appeared to depart from Constitutional Commission records, which reflected a more liberal approach to impeachment.
UP Law Associate Dean Paolo Tamase said the forum did not aim to relitigate the 2025 complaints but to examine whether impeachment “has changed for good and if so, for the better.”
Despite their criticisms, the panelists acknowledged that the unanimous en banc ruling is final and must be respected, even as debate continues over its implications for future impeachment proceedings.
