MANILA, Philippines — A new dispute over the voting rules in Vice President Sara Duterte’s impeachment trial is putting the Senate impeachment court under renewed scrutiny, with Manila Rep. Bienvenido “Benny” Abante Jr. questioning whether senator-judges who have not participated in the proceedings should be included in determining the final vote.
Abante said Friday that fairness and justice should guide the Senate’s decision as it considers whether the constitutional requirement of a two-thirds vote should continue to be calculated from all 24 senators or from a smaller group of senators legally and physically able to participate in the proceedings.
The question is significant because Senate Presiding Officer Francis “Chiz” Escudero had previously ruled that 16 votes—two-thirds of the 24-member Senate—are required to convict Duterte.
That ruling is now being challenged after several senator-judges have been unable to participate in the trial.
The question behind the 16-vote rule
Article XI, Section 3(6) of the 1987 Constitution states that an impeached official cannot be convicted without the concurrence of two-thirds of all the Members of the Senate.
The controversy centers on what exactly “all the Members of the Senate” means in an impeachment proceeding.
Does it automatically mean all 24 sitting senators?
Or should senators who are legally unable to participate, absent throughout the proceedings, detained, abroad or otherwise prevented from exercising their duties be excluded from the computation?
Senator-judge Erwin Tulfo previously raised the issue, pointing to senators who have been unable to participate in the trial and warning that maintaining a fixed 24-member denominator could effectively allow absences to affect the outcome.
The Senate impeachment court subsequently invited retired Supreme Court magistrates to provide independent legal opinions on the issue.
Former justices divided on the issue
The opinions presented before the impeachment court on September 16 revealed significant differences.
Former Chief Justice Hilario Davide Jr. said senators who are legally or physically unable to participate should not automatically be included in the voting base. His position was that the constitutional phrase should refer to senators who are qualified to perform their duties in the impeachment proceeding.
Former Chief Justice Artemio Panganiban also questioned whether a senator-judge who did not attend the proceedings could fairly participate in the final judgment.
Panganiban argued that senator-judges who were absent did not personally hear the testimony, examine the evidence during the proceedings or observe witnesses.
Former Chief Justice Reynato Puno likewise supported considering whether senators are actually capable of participating in the proceedings when determining the voting base.
But former Supreme Court Associate Justice Adolfo Azcuna took a different position. He argued that the Senate’s full membership should continue to form the basis for the two-thirds requirement unless a Senate seat becomes permanently vacant.
That means the four retired magistrates did not arrive at a unanimous interpretation of the Constitution.
Abante: The issue goes beyond the number 16
Abante said the Constitution does not explicitly state “16 votes.” Rather, it requires concurrence from two-thirds of the Senate’s members.
“Wala namang sinabing 16. Ang sinabi, two-thirds of all members,” Abante said, according to the House of Representatives. He described the meaning of “all members” in the present circumstances as a gray area for the impeachment court to resolve.
Abante also raised the question of whether it would be fair for a senator-judge who did not follow the presentation of evidence to participate in the final judgment.
His comments echo the concern raised by Panganiban, who questioned whether a senator who had not been present could properly evaluate the evidence and testimony presented during the trial.
At the same time, other legal views presented to the Senate indicate that absence does not necessarily prevent a senator from deciding based on the official trial record, including transcripts, recordings and documentary evidence. Philstar reported that Puno and Azcuna maintained that senator-judges could rely on the record even if they were not physically present throughout the proceedings.
The Senate faces a critical September 23 vote
The Senate impeachment court is scheduled to hear oral arguments from the prosecution and defense on September 23, after which senator-judges are expected to act on the challenge to the existing 16-vote threshold.
Until the court changes the ruling, 16 votes remain the governing threshold.
The situation became even more complicated after impeachment court spokesman Reginald Tongol clarified that there are currently 20 active senator-judges and that 11 votes could constitute a majority if all 20 are treated as the voting base for the appeal itself. He also clarified that Escudero will participate in the vote despite being the senator whose ruling is being challenged.
The separate question of how many votes would ultimately be required to convict Duterte, however, remains unresolved.
Both sides prepare for the threshold fight
The House prosecution has said it intends to focus on the evidence regardless of whether the Senate ultimately retains the 16-vote requirement or adopts another interpretation.
Rep. Jonathan Keith Flores said the prosecution would “sink or swim with the evidence” it presents to the impeachment court, regardless of whether the threshold is 16, 14 or 13 votes.
Duterte’s defense team, meanwhile, has said it is preparing its arguments for the September 23 proceedings and has not yet publicly disclosed its final position on the disputed threshold.
The dispute therefore remains a constitutional and procedural question rather than a settled change to the conviction threshold.
What happens next?
The immediate focus will be the September 23 oral arguments and subsequent Senate action.
For Abante, however, the larger question is whether every senator counted in the final vote should have had a meaningful opportunity to participate in the impeachment proceedings and assess the evidence.
The Senate must ultimately determine how the constitutional phrase “two-thirds of all the Members of the Senate” applies to the unusual circumstances surrounding the current impeachment trial.
Whatever interpretation the impeachment court adopts could determine not only the number of votes required in Duterte’s case but also how similar questions are handled in future Philippine impeachment proceedings.
The key question now is no longer simply whether the threshold is 16 votes—it is who should be counted when that threshold is calculated.
