A series of opinion columns written by National Bureau of Investigation (NBI) Director Melvin Matibag criticizing Vice President Sara Duterte became the centerpiece of the defense's cross-examination on Tuesday, as her lawyers questioned whether the NBI chief had already formed a judgment on her before overseeing an investigation that later became part of her impeachment trial.

Defense lawyer Mark Vinluan pressed Matibag over three columns he wrote for the Daily Tribune in 2024 — "Inday Sara, the Bratinella," "The Bratinella is a Flat Spare Type," and "Bratinella, Sara, and Her Bad Habits" — asking whether he was the author of the pieces.

Matibag confirmed that he wrote the columns but said they reflected his views as a columnist and were separate from his duties as NBI director.

In one of the columns, Matibag discussed the impact of the congressional investigations on Duterte's public standing and cited survey results showing changes in her trust and approval ratings.

Vinluan compared the column with a Social Weather Stations (SWS) survey presented during the hearing showing Duterte with a 57 percent public trust rating. He asked Matibag whether he still stood by his previous assessment despite the survey results.

Matibag said the column reflected his personal opinion at the time and was unrelated to the NBI's investigation.

“As NBI director, I don't think this is material,” Matibag said, adding that the bureau's findings were based on evidence, the law, and the investigative process.

“A survey is just a snapshot of what's happening. It doesn't necessarily follow that once it comes out, that's the truth,” Matibag told the impeachment court.

Matibag was appointed NBI director in February 2026, placing him at the helm of the agency when it created a special task force to investigate Duterte's November 2024 remarks in which she said she had arranged for President Ferdinand Marcos Jr., First Lady Liza Araneta-Marcos, and then-House Speaker Martin Romualdez to be targeted if she were killed.