The Integrated Bar of the Philippines (IBP) defended the legality of the Senate's June 3 session, asserting that the chamber validly conducted business despite the presence of only 12 senators.

The IBP, in a statement, said the session met constitutional quorum requirements, citing long-standing Supreme Court (SC) jurisprudence that allows the Senate to continue functioning when some members are unavailable and cannot be compelled to attend.

The lawyers' group pointed to the landmark 1949 Supreme Court ruling in Avelino v. Cuenco, which adopted a practical approach in determining quorum and recognized the need to prevent legislative paralysis due to unavoidable absences.

It cited that the Constitution requires a majority of each House to constitute a quorum, but jurisprudence has clarified that this refers to a majority of members who are available and capable of participating in legislative proceedings. 

The group noted that while the Senate has 24 seats, only 22 members were considered available during the June 3 session. 

According to the IBP, one senator was under detention for a non-bailable offense, while another's whereabouts were reportedly unknown, making them effectively unavailable for Senate proceedings.

With 12 senators in attendance, the IBP said the chamber still had the majority required to conduct official business.

The statement comes amid questions raised over the validity of actions taken during the session, where only half of the Senate's full membership was physically present.

The IBP stressed that all resolutions, decisions, and proceedings undertaken during the session enjoy the presumption of regularity and are considered official acts of the Senate unless overturned through proper legal processes.

According to the organization, the Avelino doctrine remains relevant because it safeguards the continuity of legislative functions, ensuring that Congress can perform its constitutional duties even when some members are absent due to circumstances beyond the institution's control.