MANILA, Philippines — The battle over the number of votes needed to convict Vice President Sara Duterte is entering a critical stage, with former lawmaker and House Deputy Speaker Janette Garin arguing that senators who are unable to perform their duties should not be included in calculating the two-thirds threshold.
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Garin said the constitutional requirement should be based on the members of the Senate who are legally and practically capable of carrying out their duties as senator-judges.
Her position comes as the Senate impeachment court prepares for oral arguments on September 23 on whether its earlier ruling requiring 16 votes from the 24-member Senate should remain in force.
The dispute could determine the mathematical threshold that will ultimately apply when senator-judges vote on Duterte’s impeachment case.
Why the 16-vote rule is being challenged
Article XI, Section 3(6) of the 1987 Constitution provides that an impeached official cannot be convicted without the concurrence of two-thirds of all the Members of the Senate.
Since the Senate has 24 members, Presiding Officer Francis “Chiz” Escudero initially interpreted the provision to mean that 16 votes are required for conviction, regardless of whether all senators are able to participate.
That interpretation has now been challenged.
Senator-judge Erwin Tulfo asked the impeachment court to reconsider the ruling, arguing that senators who cannot participate in the proceedings should not necessarily remain part of the denominator used to calculate the two-thirds requirement.
The issue became more complicated because several senators are currently unable to participate in the impeachment proceedings for different reasons.
Senators Jinggoy Estrada and Rodante Marcoleta are detained in connection with separate plunder cases. Senator Ronald “Bato” dela Rosa has been absent and has not taken the oath required for senators sitting as impeachment judges, while Senator Loren Legarda has been on medical leave abroad.
Former justices split over the meaning of “all members”
The Senate impeachment court brought in four retired Supreme Court magistrates as amici curiae, or “friends of the court,” to provide legal guidance on the constitutional question.
Their views did not produce a single interpretation.
Retired Chief Justices Artemio Panganiban, Reynato Puno and Hilario Davide Jr. expressed positions supporting an interpretation in which senators who are legally or practically unable to participate could be excluded from the voting denominator.
Davide, in particular, said senators who are detained, abroad, suspended or whose whereabouts are unknown should not automatically be included in the phrase “all the Members of the Senate.”
Retired Associate Justice Adolfo Azcuna, however, took the opposite position. He maintained that the constitutional language refers to Senate membership itself, meaning the full 24-member Senate should remain the denominator.
In short, the former magistrates disagreed over whether the constitutional phrase should be applied literally to the entire Senate membership or interpreted in light of the senators actually qualified and able to participate.
Carpio offers another calculation
Retired Supreme Court Associate Justice Antonio Carpio has also weighed in, saying that only 21 senators are currently qualified to vote.
Carpio argued that senators who are detained or suspended from performing their official duties should not be counted in the denominator. He also pointed to Dela Rosa’s failure to take the required oath as a senator-judge.
Under that interpretation, the mathematical threshold would no longer automatically be 16 votes.
However, Carpio’s view is only one legal interpretation and does not constitute the Senate impeachment court’s final ruling.
The Senate still has the final say for now
The Senate impeachment court has scheduled September 23 for oral arguments from the prosecution and defense on the threshold issue.
The senator-judges are then expected to vote on whether to sustain or overturn Escudero’s earlier ruling.
The mechanics of that vote have themselves generated another procedural question. Senate impeachment court spokesperson Reginald Tongol previously clarified that 11 votes among the active senator-judges would be needed to overturn the 16-vote ruling, correcting an earlier statement that 10 votes would suffice.
If the Senate changes the voting base, the eventual number required for conviction could therefore be lower than 16.
But if the court retains the interpretation that all 24 senators must be counted, 16 votes would remain necessary for conviction.
The issue is bigger than a simple numbers game
The dispute is ultimately about how the Constitution should operate when members of the Senate remain legally elected senators but are unable to participate in an impeachment proceeding.
Panganiban argued that circumstances involving absent or unavailable senators should not make the impeachment process incapable of producing a decision. Meanwhile, Azcuna warned against changing the denominator depending on circumstances, maintaining that “all” members means the full membership of the Senate.
The debate has also raised questions about the relationship between the Senate’s impeachment authority and the Supreme Court’s power to review constitutional issues.
Panganiban has said the Senate impeachment court has the authority to interpret the constitutional provision for purposes of the impeachment proceeding, while acknowledging that judicial review could arise if constitutional limits or grave abuse of discretion become an issue.
Malacañang, meanwhile, has said it will leave the question to the Senate and will not issue its own judgment on whether the threshold should be based on all 24 senators or only those able to participate.
For now, the central question remains unanswered:
Will “two-thirds of all the Members of the Senate” continue to mean 16 votes from all 24 senators—or will the impeachment court determine that senators who are legally unable to participate should be removed from the calculation?
The Senate’s September 23 proceedings are expected to provide the next major answer in the closely watched impeachment trial.
