SEN. Panfilo Lacson on Friday criticized Senate President Alan Peter Cayetano for refusing to bring his dispute with the Senate’s new leadership before the Supreme Court.
In a post on X, Lacson cited a newspaper story that compared the Senate leadership transition on June 3 with the 1949 dispute that led to the removal of Jose Avelino as Senate president.
“Thank you for plainly explaining all the similarities in the two Senate controversies; the only difference being that Avelino brought his case to the Supreme Court. Cayetano does not have Avelino’s decency and respect for the same rule of law,” Lacson said.
He made the remarks in the aftermath of a power play that saw a new majority bloc assume control of the Senate.
According to the report cited by Lacson, the 1949 controversy unfolded when Avelino and his allies allegedly used procedural tactics to prevent senator Lorenzo Tañada from delivering a privilege speech that was critical of Avelino.
Avelino left the session hall after adjourning the proceedings, but the remaining 12 senators stayed on, naming senator Mariano Cuenco as presiding officer, declaring the Senate presidency vacant and electing Cuenco as acting Senate president.
Avelino challenged Cuenco’s action before the Supreme Court. In the landmark case Avelino v. Cuenco, the court addressed questions surrounding Senate leadership and quorum requirements, a ruling that continues to be cited in parliamentary disputes.
Last June 3, 12 senators — composed of what had been the minority bloc’s 11 members and Sen. Francis Escudero — convened despite senators aligned with Cayetano boycotting the session.
The group elected Sen. Sherwin Gatchalian as Senate president pro tempore and acting Senate president. The new majority maintained that a quorum existed and cited the Supreme Court’s ruling in Avelino v. Cuenco as a precedent.
Cayetano rejected the legitimacy of the shift in leadership and insisted he was Senate president.
The controversy escalated on Thursday when Cayetano and several allies arrived at the Senate a day after Congress had adjourned sine die and conducted what they described as a committee hearing.
The hearing was deemed illegal by the new Senate leadership.
On Friday, Senate President Pro Tempore Loren Legarda said the 1949 Supreme Court ruling in Avelino v. Cuenco cannot be invoked to justify the reorganization of the Senate.
Legarda, who belongs to Cayetano’s camp, maintained that the Constitution and the Rules of the Senate require a majority vote of all members for the election or replacement of Senate officers.
“A 12-senator session cannot be used to reorganize the Senate,” Legarda said in a statement. “The Constitution recognizes a 24-member Senate, and both quorum and the election of officers require a majority of that membership. That number is thirteen.”
Legarda said the doctrine established in Avelino v. Cuenco must be understood within its historical and constitutional context. The case was decided in 1949 under the 1935 Constitution, which only provided that the Senate shall elect its president and did not specify the number of votes required.
She noted that the constitutional framework later changed. The 1973 Constitution introduced the requirement that legislative leaders be elected “by a majority vote of all its Members,” a provision that was retained in Article VI, Section 16(1) of the 1987 Constitution for the election of the Senate president and the speaker of the House of Representatives.
Legarda said the insertion of the phrase “by a majority vote of all its respective Members” was deliberate and must be given effect.
“Under settled principles of constitutional construction, no word, phrase or amendment is presumed to have been placed in the Constitution for nothing,” she said. “The change from the 1935 text to the 1973 and 1987 Constitutions must therefore be read as intentional.”
Legarda also said the Rules of the Senate do not alter the Constitution but simply implement its requirements. Rule II, Section 2 states that Senate officers shall be elected by “the majority vote of all its members.”
The rule covers the Senate president, Senate president pro tempore, secretary of the Senate and sergeant-at-arms.
“Nothing is different here. The Rules only follow the Constitution,” Legarda said. “If the Senate President needs the majority vote of all members, Rule II, Section 2 applies that same standard to all Senate officers. In a 24-member Senate, that standard has only one meaning: 13 votes.”
She warned that conflating quorum requirements with the election of officers would lead to an untenable result.
“If Avelino were stretched to allow the election of officers based only on a reduced quorum or the number actually present, then even seven or eight senators could theoretically claim authority to reorganize the Senate,” she said. “That cannot be what the Constitution means.”
A high school teacher has asked the Supreme Court to rule on the legality of the June 3 Senate session that triggered a leadership shift in the chamber, even as legal experts and the Integrated Bar of the Philippines (IBP) separately maintained that the disputed session was valid under constitutional standards and established jurisprudence.
In a 20-page petition for certiorari filed on Friday, private school teacher Barry Tayam urged the court to determine whether the participation of 12 senators during the contested session constituted a valid quorum, and whether the actions taken — including leadership changes and committee reorganizations — are binding and constitutional.
Tayam named Senate President Alan Peter Cayetano, and Senators Pia Cayetano and Legarda as respondents, alleging they continued to assert leadership and committee positions despite what he described as a new majority emerging during the June 3 session.
Tayam said he filed the case as a taxpayer and registered voter.
He said the dispute has sowed confusion among the public and legal observers, requiring judicial clarification.
The petition is the first case elevated to the Supreme Court arising from the Senate leadership row.
Tayam asked the Court to declare that the “physical presence and assembly” of 12 senators constituted a lawful quorum. He argued that even under alternative computations of membership, the threshold for a quorum was met.
In a statement, the IBP said the Senate session was validly constituted despite the presence of only 12 senators, invoking both the Constitution and Avelino v. Cuenco.
The IBP said that “majority of each House” has been interpreted by the Supreme Court not as all elected members, but as those considered constituting the House for legislative business. It added that the Court has recognized a distinction between a majority of all members and a majority of the House, with the latter requiring a lesser number.
The IBP further argued that two senators were effectively unavailable during the June 3 session — one detained in connection with a non-bailable offense and another reported missing since May 11 — placing them beyond the Senate’s immediate reach.
On that basis, the Senate had 22 “available” members, meaning 12 senators constituted a majority sufficient for a quorum.
“In light of the foregoing, the Senate session of June 3, 2026, was lawful and valid following the Avelino doctrine,” the IBP said.
It also stressed that legislative acts are presumed valid under the presumption of regularity unless overturned by proper legal action.
A similar position was raised by a group of law deans, professors of juridical science, political theorists and canon law experts, who warned that continued uncertainty over quorum and leadership could paralyze the Senate and erode public trust.
In their statement, the group said the public and Senate staff have been left confused by competing claims of authority, raising concerns about institutional stability.
Among the signatories were Lingayen-Dagupan Archbishop Socrates Villegas, retired Supreme Court Associate Justice Adolfo Azcuna, former UP Law Dean Pacifico Agabin, Ateneo School of Government former dean Antonio La Viña and San Beda Law Dean Ranhilio Callangan Aquino, along with other academics and legal scholars.
They urged senators to return to legislative work and move forward with pending matters, including the impeachment trial of Vice President Sara Duterte.
The co-convenor of the opposition-led Tindig Pilipinas described Thursday’s Blue Ribbon Committee hearing as “incredulous.”
In a Messenger chat to The Manila Times late on Thursday, Kiko Aquino-Dee, who also led the Trillion Pesos Marches against corruption last year, said he does not understand the logic of including figures like Sen. Vicente Sotto III and Mamamayang Party-list Rep. Leila de Lima. Both were out of office when the so-called 18 Marines testified during the hearing.
“That’s not to say that there’s absolutely no truth in the testimony. I imagine many people really did receive those maletas (luggages), but I think the only way we can get to the bottom of things is to have both factions of the Senate present to interpellate the Marines’ testimony,” Aquino-Dee said.
He said he agrees with the arguments presented by the majority bloc led by Gatchalian. “The Constitution gives any number of senators the power to compel their fellow senators’ attendance, but if senators like Bato [dela Rosa] and Jinggoy [Estrada] are beyond their coercive power, then the constitutional remedy is no longer available, and it stands to reason to reduce the threshold for quorum as we’ve seen previously when Jinggoy along with Bong Revilla and the late Juan Ponce Enrile were arrested during the [Priority Development Assistance Fund] scandal,” Aquino-Dee said.
He said the Cayetano camp has the right to argue its own interpretation. “If they can’t talk things over with their peers in the Gatchalian side, then the Supreme Court seems to be the only entity that can break the stalemate,” he added.
In a statement posted on Sen. Francis Pangilinan’s Facebook page, former senators Aquilino Pimentel III and Franklin Drilon, as well as incumbent Senators Juan Miguel Zubiri and Vicente Sotto III, said they are calling for a “de-escalation” of public rhetoric that demeans the Senate and weakens the confidence in the chamber.
“Those of us who once held the gavel know that the highest duty of a Senate President is not to cling to office but to leave the institution stronger, more respected and more firmly bound to the rule of law than when he or she found it,” the senators wrote.
The urged “all incumbent senators, regardless of bloc or affiliation, to de-escalate public rhetoric that demeans the Senate and weakens confidence in it; to confine their disagreements to the floor and to the proper forums, where the arguments and the votes can be scrutinized by the public; and to prioritize the urgent work before the Senate (the economy, food and energy security and justice) over internal maneuvering.”
