Impeach court revisiting ‘2/3’ conviction rule

MANILA, Philippines — The Senate impeachment court will revisit the voting threshold required to convict Vice President Sara Duterte, with legal experts set to weigh in on the matter on Sept. 16 before the prosecution and defense present their arguments on Sept. 23.

The court’s presiding officer, Sen. Francis “Chiz” Escudero, ruled to have it taken up after Senator-judge Erwin Tulfo on Tuesday formally asked the body to reconsider Escudero’s July 6 pronouncement that a vote by two-thirds of all 24 senators—or 16 votes—is needed for a conviction.

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.”

Article continues after this advertisement

The dispute centers on whether “all members” should mean all 24 senators regardless of their ability to participate, or only those legally able to take part in the impeachment proceedings and final vote.

FEATURED STORIES

NEWSINFO

NEWSINFO

NEWSINFO

READ: Highlights: Day 23 of Sara Duterte impeachment trial | Sept. 8, 2026

Four senators are currently unable to attend the trial: Ronald “Bato” dela Rosa, who is in hiding because he faces an arrest warrant from the International Criminal Court; Jinggoy Estrada and Rodante Marcoleta, who are detained on the nonbailable charge of plunder before the Sandiganbayan; and Loren Legarda, who is abroad on an extended medical leave.

Escudero said the court would not immediately resolve Tulfo’s appeal through the usual ayes-and-nays voting because of the “sensitive and serious nature” of the issue.

Instead, the court will hear from amici curiae, or “friends of the court,” on Sept. 16. The prosecution and Duterte’s defense will each be given 15 minutes to present their positions during oral arguments on Sept. 23, after which the Senate will vote on the threshold question.

Article continues after this advertisement

Escudero said the legal experts could provide independent expertise and perspectives on the constitutional issue. Their names have yet to be announced as the court is still confirming their availability.

Legal experts split

Senator-judge Francis “Kiko” Pangilinan said the amici could include eminent legal experts, retired chief justices or Supreme Court justices, and constitutional law specialists.

Article continues after this advertisement

The question has already drawn differing views from retired Supreme Court justices and a former president of the Integrated Bar of the Philippines (IBP).

Former Supreme Court Associate Justice Adolfo Azcuna, in an ANC interview on June 19, said he believed the 16-vote requirement should remain because the Constitution refers to the membership of the Senate, not merely those physically present.

“My view is that the voting threshold is based on the number of members of the Senate whether or not those members are present or able to actively participate,” Azcuna said.

“As long as they remain members of the Senate they should be counted in computing the two-thirds,” he added, maintaining that the threshold remained 16 because the four senators unable to participate were still members of the chamber.

Azcuna, however, raised a possible exception involving Dela Rosa, saying that if the senator is legally considered a fugitive, his status could potentially amount to a constructive resignation because he had placed himself outside the legal system.

Retired Supreme Court Senior Associate Justice Antonio Carpio took a different position.

In a June 21 post on his website, Carpio argued that the two-thirds computation should be based on senators who are legally qualified to participate in the proceedings.

“If you cannot hold office, you cannot vote,” Carpio said.

Carpio nevertheless noted that Dela Rosa remained a qualified senator because he had neither been suspended nor removed from office.

Former IBP president Domingo Cayosa, meanwhile, said in an interview with the Inquirer on July 11 that the 16-vote threshold could be lowered to reflect the senators actually able to participate in the impeachment trial.

Cayosa described this as a “fair and practical” reading of the Constitution, saying it was consistent with the Charter’s spirit, which he characterized as “not restrictive.”

The operative phrase, he said, was “two-thirds” of all members of the Senate.

Estrada, Dela Rosa and Marcoleta “are all alive and are not yet unseated by any of the constitutionally allowed modes of removal, so they are still senators,” Cayosa said. “Except when they transform themselves into an impeachment court, they all become judges.”

That distinction, he said, creates a constitutional nuance: “because how can you be a judge when you were not there, [and] you did not observe and participate.”

But Cayosa acknowledged that a “simple and strictly literal” reading of the Constitution, particularly from the defense’s perspective, would keep the threshold at 16.

Tulfo seeks clarification

Tulfo raised the issue on Tuesday, asking whether senators who are unable to attend the trial should nevertheless be allowed to vote.

“When we refer to all members, who exactly are we counting?” Tulfo asked.

He questioned whether the absent senators’ votes would be accepted despite their nonparticipation, or whether their absence would effectively count as a vote against conviction.

Tulfo warned that retaining a fixed 24-member voting base could result in an “acquittal by default” if enough senators were unable to cast votes.

He cited Avelino v. Cuenco, which he said considers members within the Senate’s coercive jurisdiction in determining the voting base and quorum.

Senator-judge Pia Cayetano disputed the argument, saying it was inaccurate to suggest that the Senate had adopted the Supreme Court ruling as its governing rule.

Escudero clarified that Tulfo’s appeal seeks a determination of what constitutes “all members” under the Constitution. He also pointed out that changing the voting base would affect not only the two-thirds requirement for conviction but also the one-third threshold for acquittal.

Tulfo said the matter should be resolved quickly because the trial calendar has been expedited, with the prosecution dropping several witnesses and Duterte’s defense indicating it might not present its own case.

“These developments … could bring the court to the final question sooner than expected,” Tulfo said.

He stressed that he was not seeking to make conviction easier, but to settle how the constitutional requirement should operate under the Senate’s present circumstances.

“What we should ask ourselves this time … should the constitutional design of making impeachment difficult, override equally important constitutional demand for accountability?” he said.

Your subscription could not be saved. Please try again.

Your subscription has been successful.

Escudero said the court would take the matter under advisement, hear the amici and the parties, and then decide. —With a report from Inquirer Research