The Integrated Bar of the Philippines and law experts declared a 12-senator quorum during the June 3, 2026 session lawful, citing the 1949 Supreme Court Avelino v. Cuenco doctrine.
Senator Alan Peter Cayetano rejected the leadership shake-up, arguing that at least 13 senators are required to elect a new Senate President.
The 12-member bloc excluded missing Senator Ronald dela Rosa and detained Senator Jinggoy Estrada from the quorum base, subsequently electing Senator Sherwin Gatchalian as presiding officer.
TWELVE senators could form a valid quorum during the Senate session on June 3, 2026, the Integrated Bar of the Philippines and a group of law deans and professors said, as Sen. Alan Peter Cayetano maintained that the leadership shake-up was invalid.
In a statement on Thursday, June 4, the IBP said the session was lawful under the Supreme Court’s (SC) 1949 ruling in Avelino v. Cuenco, which allowed the Senate to determine quorum based on the number of senators available to take part in proceedings.
A similar separate statement was also issued by law deans, law professors and political analysts, posted on the Facebook page of San Beda University Graduate School of Law dean Fr. Ranhilio Aquino.
Basis of the quorum
The IBP cited Article VI, Section 16(2) of the 1987 Constitution, which states that “a majority of each House shall constitute a quorum to do business.”
It said the SC had applied a practical reading of a similar provision in the 1935 Constitution in Avelino v. Cuenco, ruling that a majority may be determined based on senators who could take part in Senate proceedings.
The IBP said two senators should be excluded from the quorum count because their attendance could not be compelled. The organization was referring to Sen. Ronald “Bato” dela Rosa and Sen. Jinggoy Estrada. Dela Rosa’s whereabouts have been unknown since May 14, 2026 three days after his surprise, while Estrada is under detention for plunder charges related to flood control projects.
With the two senators excluded, the IBP said 22 senators should be treated as available, making 12 senators a majority for purposes of quorum.
“In short, the Senate session of June 3, 2026 was lawful and valid following the Avelino doctrine because a quorum of 12 Senators was constituted,” the IBP said.
The IBP said Senate acts and resolutions approved during the session are presumed to be official acts under the presumption of regularity in the discharge of public functions.
Academic backing
Meanwhile, law deans and professors said the public has been left confused by the Senate leadership dispute, while Senate employees may be unsure whose orders to follow.
“Our people are confused – and they are weary of the incessant wrangling that threatens the credibility of an institution essential to the workings of our democracy,” the statement said.
The group said counting Dela Rosa in the quorum would allow a senator beyond the reach of legal processes to hold the legislature hostage.
The signatories said Avelino v. Cuenco remains applicable despite being decided under the 1935 Constitution because the Senate has kept its 24-member composition under the 1987 Constitution.
They cited a May 5, 2015 incident when then Senate President Franklin Drilon declared a quorum with 12 senators out of 17 available senators, with others unavailable because they were abroad or under detention.
“This was not unconstitutional. It was allowing function to prevail over literal insistence on a given number,” the statement read.
The group rejected the argument that 12 senators could not constitute a quorum because 13 is treated as the majority of 24.
“The question has been asked: Since when has 12 become 13, and the plain answer is never, but the premise is mistaken, because it assumes that 13 is the magic number for a quorum,” it said.
Cayetano’s stand
Cayetano has rejected the June 3 proceedings, saying at least 13 senators are needed to elect a new Senate President.
The 12-member bloc convened on June 3, declared a quorum based on the recognized base number of 22 senators under the Avelino v. Cuenco ruling, and moved to vacate all Senate leadership positions after no objection was raised.
Sen. Sherwin Gatchalian, who was elected Senate President pro tempore, has since acted as the chamber’s presiding officer. He was not elected Senate President because the Constitution requires 13 votes for the post.
The law deans and professors said a senator who can count on 11 votes, including his own, cannot continue to assert leadership over the chamber if 12 senators have chosen to support Gatchalian as presiding officer.
The group called on senators to return to work and attend to urgent matters, including the impeachment trial of Vice President Sara Duterte.
Among the signatories were Lingayen-Dagupan Archbishop Socrates B. Villegas; retired Associate Justice Adolfo S. Azcuna; former University of the Philippines College of Law dean Pacifico Agabin; University of Asia and the Pacific Law School dean Jemy Gatdula; Aquino; San Beda University Graduate School of Law professor Edmund Tayao; and former Ateneo de Manila University School of Governance dean Antonio La Viña. / KAL