A law dean on Wednesday questioned the Senate’s position that 16 votes remain the threshold for conviction in an impeachment trial even if some senators are absent, arguing that the Constitution’s two-thirds requirement should apply only to senators who actually participate in the proceedings.

Rev. Fr. Ranhilio Aquino, dean of the Graduate School of Law at San Beda University, said the phrase “two-thirds of all the Members of the Senate” assumes that all senators counted in the computation have heard the evidence and taken part in deliberations before voting.

“The premise of the Constitution when it says two-thirds of all senators is that all of them listened to the evidence and discussed it with their colleagues before making a decision,” Aquino said in Filipino during a radio interview.

Aquino maintained that absent senators should not be included in determining the number of votes needed for conviction, saying the threshold should not be treated as a fixed number.

“Two-thirds cannot be a fixed number. The premise of the Constitution when it says two-thirds of all senators is that all of them listened to the evidence and discussed it with their colleagues before deciding,” he said.

He questioned the fairness of counting absent senators as effectively votes for acquittal.

“What if those who did not appear were absent because they were detained or hiding? They did not hear the evidence, they did not examine the documents. How can you count them? Just because a senator is absent, you count their vote as acquittal? That’s not fair at all,” Aquino said.

Aquino cited a hypothetical situation where several senators could no longer participate in the trial.

“Let’s say nine senators died in a plane crash — this is hypothetical. Would you still count two-thirds of 24 even if nine are already dead? That is absurd,” he said.

He also pointed to the impeachment rules of the United States Senate, which require a two-thirds vote of senators present for conviction, saying the same principle should guide the interpretation of the Philippine Constitution.

“I maintain that two-thirds is not a fixed number but two-thirds of all senators who participated in the impeachment trial,” Aquino said.

The Senate has maintained that 16 votes remain necessary for conviction, based on the constitutional requirement of a two-thirds vote of all senators.