

Senate President Win Gatchalian ruled out petitioning the Sandiganbayan to allow detained Senator Jinggoy Estrada to attend the upcoming impeachment trial of Vice President Sara Duterte, despite Senator Ping Lacson's concern that his absence could harm voting urnout.
“We cannot file [a petition to] the Sandigan because we are not a party of interest. It’s between the respondent and also the state. We’re not involved in that,” he told reporters in his first briefing as the official Senate leader.
Estrada on Tuesday was slapped with a 90-day preventive suspension by the Sandiganbayan over his pending graft and plunder charges tied to the alleged anomalous flood control projects.
This effectively bars Estrada from performing his legislative duties pending the investigation.
According to Gatchalian, this measure is not limited to Estrada’s role as a legislator but also applies to his role as a senator-judge in the impeachment trial of Vice President Sara Duterte.
Over the weekend, Lacson raised concerns that Estrada’s prolonged detention, the continued hiding of Senator Bato dela Rosa, and the possibility of suspension of several of their colleagues could further reduce the number of senator-judges in the impeachment trial, making it impossible to meet the required voting threshold.
Article XI, Section 3(6) of the Constitution sets the required number of votes to convict an impeached official at 16, which is equivalent to two-thirds of the 24-member Senate.
Lacson’s remarks follow Ombudsman Boying Remulla’s earlier announcement that approximately nine to 10 senators are under investigation for alleged involvement in the multibillion-peso flood control scandal.
Lacson feared that this could put the Senate impeachment court in a crisis, given that the Constitution mandates 16 votes to convict an impeached official.
Due to this, he suggested that the Senate file a motion asking the Sandiganbayan to allow detained senators to participate in the impeachment trial in person under police escort, unless there is a preventive suspension by the Ombudsman.
No waiver for suspended senators
Former Supreme Court associate justice Adolfo Azcuna explained to the Daily Tribune that a preventive suspension is mandatory and thus cannot be waived.
Though he called Lacson’s proposal of petitioning the Ombudsman to delay a preventive suspension to allow senators to attend the trial “far-fetched but possible.”
Azcuna, one of the framers of the 1987 Constitution, maintained that the “Senate cannot lower the threshold for conviction unless it expels a member or possibly declares him or her as resigned.”
Although he emphasized that several law experts from their group, called “Citizens’ Jury,” are of the view “that those unable to actively participate should not be included in the count.”
As for absent senators, their votes are automatically counted as abstentions, according to Azcuna.
Some legal experts and House prosecutors have argued that the threshold should be calculated based on the actual number of participating senator-judges.
This stemmed from concerns that the potential absence of several senators due to threats of arrest or suspension could leave the Senate mathematically incapable of reaching the mandatory 16-vote threshold.
Despite potential challenges to voting turnout, Gatchalian confirmed that the Senate is making no effort to urge the Sandiganbayan to allow Estrada to participate in the trial scheduled for 6 July.
Threshold still fixed at 16
The Senate leader also reiterated that the conviction threshold remained fixed at 16 votes, regardless of how many senators attend the trial.
A conviction carries a penalty of removal from office and perpetual disqualification from holding one. This could derail Duterte's presidential bid in the 2028 elections.
The defense team of VP Duterte and House prosecutors faced off during pre-trial briefing on Thursday, two weeks ahead of the trial proper. Several senators claimed that Senator Chiz Escudero would preside over the trial. However, Gatchalian seemed reluctant, saying the majority bloc has yet to reach a consensus and the same is still subject to the group's approval.
Both camps tackled procedural matters and finished the marking of evidence, though the proceedings were not open to the media.
Lawyer Michael Poa of the defense team told reporters that there were disagreements and a brief suspension due to tense exchanges, though he noted that it was part of the pre-trial phase.
The VP is facing allegations of betrayal of public trust, culpable violation of the Constitution, graft and corruption, and other high crimes. She was first impeached on 5 February last year. However, the Supreme Court unanimously struck it down on a technicality before the Senate could hold a trial proper.
The charges are primarily related to the alleged misuse of over P600 million in confidential funds, unexplained wealth, and a plot to have Marcos, First Lady Liza Araneta-Marcos, and former House speaker Martin Romualdez killed.
The secret funds were allocated to her office (P500 million) and the Department of Education (P112.5 million), which she headed for two years from June 2022 to June 2024.
Duterte has repeatedly dismissed the allegations of wrongdoing, deriding the impeachment proceedings as a fishing expedition and politically motivated, aimed at derailing her plans to run for president in 2028.