FUTURE Senate impeachment tribunals retain the authority to determine their own voting thresholds, as the ruling modifying the conviction requirement in Vice President Sara Duterte’s impeachment trial applies exclusively to her case, legal experts and lawmakers clarified.
On Wednesday, September 23, the Senate sitting as an impeachment court voted 13-1 to overturn Presiding Officer Sen. Chiz Escudero’s July 6 ruling, which had mandated a fixed 16-vote requirement for conviction—representing two-thirds of the total 24-member Senate roster.
Under the new pro hac vice (for this occasion only) ruling, the two-thirds requirement will apply strictly to senators legally and physically capable of participating in the trial.
With four senators currently unable to participate—Sens. Bato dela Rosa, Jinggoy Estrada, Loren Legarda, and Rodante Marcoleta—the active voting base drops to 20, lowering the required conviction threshold.
House prosecutor Rep. Chel Diokno (Akbayan) clarified during a press conference that Senate impeachment decisions do not set binding legal precedents like Supreme Court rulings.
“We cannot equate this with judicial precedent or stare decisis,” Diokno explained, noting that because the impeachment court is a legislative body rather than part of the judiciary, future Senates maintain full constitutional authority to interpret their own procedural rules.
Escudero, the sole dissenter in Wednesday’s vote, stressed that the ruling was a procedural adjustment tailored to “extraordinary” and “unprecedented” circumstances rather than a permanent rule amendment.
He noted that while the decision holds persuasive value, it carries no binding effect on future impeachment courts.
During oral arguments, defense counsel Michael Poa warned against altering the denominator, arguing it could undermine constitutional threshold requirements for issues like martial law declarations or member expulsions.
However, prosecutors urged a functional interpretation of the Constitution.
Backing this approach, three retired Supreme Court justices advising the court—including former Chief Justice Reynato Puno—noted that the Constitution’s framers intentionally used the fraction “two-thirds” instead of the explicit number “16,” intending for the voting base to adjust flexibly when members cannot participate.