The Senate impeachment court may need to hold two separate votes to determine how many votes are required to convict Vice President Sara Duterte if senator-judges overturn the existing “hard 16” rule.

Impeachment court spokesperson Reginald Tongol said Monday that the first vote would determine whether the court should grant Senator-judge Erwin Tulfo’s appeal of presiding officer Francis “Chiz” Escudero’s July 6 ruling.

Escudero’s ruling requires 16 votes for conviction, based on two-thirds of the full 24-member Senate.

Tongol said that if a majority of senator-judges votes to reverse the ruling, the court would then have to determine a new voting base and, consequently, a new conviction threshold.

A second vote may therefore be necessary because several senators who are not currently participating in the trial are in different circumstances.

According to Tongol, the court may have to determine whether senators who are absent, on medical leave, detained, facing suspension in a criminal case, or otherwise unable to participate should still be included in the denominator used to compute the constitutional requirement of two-thirds of all Senate members.

The impeachment court is set to hear amici curiae, or friends of the court, on Wednesday, before the prosecution and defense deliver oral arguments on September 23.

Tongol said the court is targeting a vote on Tulfo’s appeal after the oral arguments, although the exact question to be submitted to the senator-judges has yet to be finalized.

He also clarified that Escudero will be allowed to vote on the appeal despite being the presiding officer whose ruling is being challenged.

Tongol said Escudero would exercise his right to vote as a senator-judge, explaining that impeachment proceedings involve a judicial and deliberative function in which every senator-judge may participate.

With 20 senator-judges currently active, Tongol acknowledged that 11 votes could constitute a majority if all 20 are included in the voting base. However, he stressed that the court has not yet finalized how the appeal and any subsequent vote on the conviction threshold will be framed.

Tulfo has maintained that his appeal is not intended to reduce the number of votes needed to convict Duterte, but to clarify whether senators who are unable to participate in the trial should still be counted among “all the Members of the Senate” under the Constitution.

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