Senator Pia Cayetano brought up the chaotic 13 May Senate shooting incident on the ninth day of Vice President Sara Duterte’s impeachment trial on Wednesday, confronting National Bureau of Investigation (NBI) director Melvin Matibag as she challenged his credibility to take the witness stand.

Before this, Cayetano had hinted last week that she would admonish Matibag, with whom she and her brother, Senator Alan Cayetano, have had a rift since the incident where NBI agents supposedly attempted to arrest Senator Ronald “Bato” dela Rosa in the Senate on an International Criminal Court (ICC) warrant.

Pia seized the opportunity to face off with Matibag by flagging supposed inconsistencies in his previous statements, as she questioned the bureau chief’s credibility as a witness for the prosecution.

Citing court rules, Pia flagged Matibag’s previous interview where he said that no one was hurt in the shooting incident despite a member of the Senate security staff being mauled by NBI agents during the 13 May incident.

“You swore an oath to tell the truth, the whole truth, and nothing but the truth, correct?” Pia asked Matibag, to which the NBI chief responded in the affirmative.

She also cited two separate interviews given by Matibag. In one, he said he was not at the scene during the shooting because he was attending an event at a nearby hotel. In another, he admitted deploying several NBI agents to the Government Service Insurance System (GSIS) building which the Senate shares.

The Senate leases its premises from the GSIS. They share one compound and are separated only by a gate.

Pia contended that under the court’s rules, a witness’ credibility is relevant in assessing the weight of his or her testimony and that he or she can be discredited “by evidence that his general reputation for truth, honesty, or integrity is bad.”

Matibag is the third witness from the NBI to testify on Article IV of the Articles of Impeachment, which centers on the alleged grave threats Duterte made against President Ferdinand Marcos Jr. in several public statements in late 2024.

The Senate impeachment court concluded the presentation of evidence on Article IV on Wednesday. It will proceed to Article I, which centers on the alleged misuse of confidential funds by Vice President Duterte when the trial resumes on Wednesday, 29 July.

Matibag was at the center of the 13 May Senate shooting controversy after he and NBI agents were blamed by then Senate President Alan Cayetano for breaching the Senate premises from the GSIS side of the building to enforce the ICC warrant against Dela Rosa, despite the latter being under the chamber’s protective custody.

The shooting occurred two days after the NBI’s first botched attempt to arrest Dela Rosa who appeared at the Senate after six months in hiding to evade the ICC warrant for crimes against humanity tied to the Duterte administration’s bloody drug war.

Aside from the Senate shooting, the Cayetanos and Matibag have publicly exchanged barbs following the NBI’s reopening of its investigation into alleged irregularities that attended the holding of the 2019 Southeast Asian Games which then Speaker Alan Peter Cayetano oversaw as chairman.