The Supreme Court (SC) dismissed the petition for "mandamus" filed by Catalino Aldea Generillo, Jr., which sought to compel the Senate to convene as an impeachment court to try charges against Vice President Sara Duterte.

According to a news release of the Office of the Spokesperson of the SC, in a 14-0-1 decision written by Associate Justice Rodil Zalameda, the SC said a "mandamus, which is meant to enforce a clear legal duty, was not

the proper remedy."

The court ruled that the Senate’s actions within its specific sphere cannot be revised or controlled by the judicial department through mandamus. 

As a co-equal constitutional body, the Senate’s exercise of its duties is beyond the SC’s power of review, except in cases involving a grave abuse of discretion, the SC explained.

However, the SC said "in the interest of equity," the SC treated Generillo's petition as one for certiorari.

The law firm Respicio and Company explained that the terms mandamus and certoriari are civil actions of 'extraordinary character.

On its website, it says: "Under Philippine remedial law, Certiorari, Prohibition, and Mandamus are special civil actions governed by Rule 65 of the Rules of Court."

"These actions are extraordinary remedies invoked to address specific types of grievances involving unlawful or improper acts or omissions of a tribunal, board, officer, or person exercising judicial or quasi-judicial functions (for certiorari), or in some instances, exercising ministerial or discretionary functions in a manner that the law does not allow," it added.

On its news release, the SC said the court sought to determine whether the Senate acted unlawfully or abused its discretion by failing to convene as an impeachment court during its session break.

Contrary to the petitioner’s claim, the SC determined that the Senate acted on the impeachment complaint in "a timely manner."

The Philippine Constitution requires the House of Representatives to act on an impeachment complaint within a specific number of session days.

However, the Constitution does establish a fixed timeframe for the Senate to begin a trial.

The Constitution simply states that the trial "shall forthwith proceed," leaving the exact timing to the Senate's discretion.

REASONABLE TIME

Meanwhile, the SC clarified the term “forthwith” as used in Article XI, Section 3(4) of the Constitution.

The court has determined that “forthwith” means within a reasonable time, the duration of which may vary depending on the specific circumstances of each case.

This interpretation provides the Senate with the necessary time to prepare for convening as an impeachment court.

While the Constitution does not specify an exact date for the trial, it is essential that the Senate avoids undue delay.

This is necessary to uphold the principle that public officers must remain accountable to the people at all times.

PETITION CONSIDERED MOOT

The SC has considered the petition moot, citing that the Senate had already begun impeachment preparations. Furthermore, the Articles of Impeachment against Vice President Duterte were nullified following the Court’s July 25, 2025 Decision and January 28, 2026 Resolution in Duterte v. House of Representatives.

A case is considered moot when subsequent events resolve the underlying issues, rendering a court ruling unnecessary. In this instance, since no Articles of Impeachment remained, there was no basis for the Supreme Court to order the Senate to convene as an impeachment court.