Manila, Sept. 16 -- All three retired top magistrates appearing before the Senate impeachment court on Wednesday took the position that the 16 votes currently required to convict Vice President Sara Z. Duterte are not necessarily fixed, while retired Supreme Court Associate Justice Adolfo Azcuna insisted that all 24 senators should be counted in computing the constitutionally required two-thirds vote.

Retired Chief Justices Hilario Davide Jr., Artemio Panganiban, and Reynato Puno took different constitutional approaches but agreed that the number required for conviction could change depending on which senators should legally be counted.

Azcuna took the contrary view, saying the threshold must be "fixed, not variable" and that all sittin...