The Senate impeachment court’s 6 July ruling, setting the conviction threshold at 16 based on the 24-member voting base, will stand in case senator-judges tie in a 10-10 vote, its spokesperson said Friday. 

Only 20 of the 21 present senator-judges will cast their vote on 23 September on the motion to overturn the ruling. This is primarily because Presiding Officer Chiz Escudero had already made a definitive position on the matter, having been the one to set the threshold at 16 in a decision handed down on the first day of the trial on 6 July.

“If the [motion to reverse the ruling] on the floor loses, the ruling will stand. It is as if it is not changed and appealed," impeachment court spokesperson Reginald Tongol told reporters in a briefing. 

“Since the ruling being appealed for reconsideration is made by him, of course, he cannot withdraw it. That decision of [the presiding officer] is set in stone,” he added.

Tongol, however, speculated that a tie vote is unlikely because only 19 senator-judges can cast votes, unless Senator Loren Legarda, who has been on medical leave abroad, shows up. 

The impeachment court tapped four retired Supreme Court justices as amici curiae (friends of the court) to help interpret Article XI, Section 3(6) of the 1987 Constitution, considering the absence of four senators from Vice President Sara Duterte’s impeachment trial. 

The provision sets the required number of votes to convict an impeached official at two-thirds, which is equivalent to 16 of the 24-member Senate.

Senators Jinggoy Estrada and Rodante Marcoleta, both detained on plunder charges, and Senator Bato dela Rosa, who remains in hiding to evade an International Criminal Court warrant, have been unable to attend the trial since the beginning. Legarda, meanwhile, has been on medical leave since 3 August amid a preliminary investigation by the Ombudsman into plunder and graft complaints. 

Critics have argued that their absence effectively altered the Senate’s composition and thereby necessitates lowering the base of conviction threshold from 24 to either 20 or 21. 

In a radio interview on Friday, retired Supreme Court senior associate justice Antonio Carpio said the base number should be 21 because Legarda remains part of the impeachment court despite her month-long absence from the proceedings.

Unlike Dela Rosa, Carpio explained that Legarda took her oath as a senator-judge, making her an eligible member who can participate in the voting.

As for Estrada and Marcoleta, who also took their oath before being detained, Carpio said they should be excluded from the count because they were suspended from performing their duties due to their plunder charges.

“They cannot vote because they have been automatically suspended by operation of law. So two-thirds of 21 is only 14,” he stressed. 

Carpio argued that the Constitution did not explicitly stipulate that the two-thirds requirement is fixed at 16, thereby lowering the threshold is not unconstitutional.

Senator Erwin Tulfo, who called for resolving the threshold issue on Tuesday, warned that insisting on the voting basis being fixed at 24 amid the absence of four senator-judges will result in an “acquittal by default” regardless of how the evidence is presented

As a result, the impeachment court scheduled a whole-day meeting with amici curiae for 16 September. The issue will be put to a vote by the senator-judges on 23 September, after the defense and prosecution panels have presented their respective positions in oral arguments, which will be held that day.

Duterte’s camp and several lawyers supportive of her have objected to putting the issue of the threshold to a vote, contending that only the Supreme Court has the power to interpret the Constitution, not the impeachment court.