Former Meta engineer Arturo Bejar testified Tuesday in the company’s Oakland trial that Meta’s internal culture prioritized user growth metrics over child safety measures, according to NPR. Bejar is not an external critic; he worked inside Meta’s systems, which gives his testimony a specific evidentiary weight that external analysis cannot match. His account — that the company knew about harms to young users and chose growth metrics over safety — is the specific ‘knowledge and continued conduct’ element the states’ legal theory requires.

WHY INSIDER TESTIMONY IS DIFFERENT  

The states’ legal theory — as ONYX explained on August 19 — requires proving that Meta knew about child safety harms and chose to optimize for engagement anyway. This requires evidence of internal knowledge, not external criticism. External critics who analyzed Instagram’s effects on teen mental health can establish what was publicly observable. An engineer who worked inside Meta’s systems can establish what Meta’s internal communications, research findings, and design decisions showed, and what choices were made in response.

Bejar’s specific account: internal culture prioritized user growth metrics over child safety measures. In the legal context, this translates to: the company had the knowledge (child safety harms documented internally); it had the choice (growth vs. safety); and it made the choice (growth). That is the knowledge-and-continued-conduct element the states need.

BEJAR’S SPECIFIC CREDIBILITY  

Arturo Bejar is not a general whistleblower with a grudge against Meta. He was an engineer who worked on Meta’s internal systems with specific visibility into how the platform processed and responded to safety concerns. His 2021 congressional letter to Mark Zuckerberg — in which he described his daughter’s experience with Instagram harassment and requested specific safety changes — is a documented, prior-to-trial account of his concerns that establishes his credibility as a genuine insider raising genuine concerns rather than an after-the-fact critic.

THE PARENT GALLERY  

Parents of children who died by suicide watched Bejar’s testimony from the courtroom gallery. ONYX’s approach, as established on August 19: these parents are the accountability claimants whose children’s deaths are the stated motivation for the litigation. Their presence in the courtroom gallery during insider testimony about internal corporate knowledge of child harm is the specific human context of what is otherwise an abstract corporate liability proceeding.

Bejar wrote to Zuckerberg in 2021. He described what his own daughter experienced on Instagram. He asked for specific safety changes. He is now testifying in federal court about what the company knew and chose to do.

META’S DEFENSE CHALLENGE  

Bejar’s insider testimony creates a specific challenge for Meta’s defense. Meta’s primary defense — that it built safeguards and did not know the specific causal connection between platform design and suicide — is directly contradicted by insider testimony that the internal culture prioritized growth over safety. Meta’s cross-examination will need to establish: that Bejar’s account is inaccurate, incomplete, or unrepresentative of the overall institutional culture; that the growth-over-safety characterization mischaracterizes decisions that had legitimate business rationales; and that the safety measures that were built are evidence of genuine institutional commitment rather than inadequate response to known harms.

WHAT HAPPENS NEXT  

▸  Meta cross-examination of Bejar — will challenge the growth-over-safety characterization and the representativeness of his account

▸  Additional insider witnesses — whether the states call additional former Meta employees with similar accounts

▸  Internal documents phase — the Meta research documents on teen mental health will be the evidentiary core; Bejar’s testimony provides the human frame for those documents

▸  Parallel legislative acceleration — Bejar’s testimony will be cited in Congressional and state legislative debates on platform youth safety

CONFIDENCE: HIGH

Bejar’s testimony at Oakland trial, NPR reporting, and parental gallery presence are from confirmed reporting. Bejar’s 2021 Zuckerberg letter is established public record. Legal theory analysis is ONYX editorial based on established tort law from August 19 coverage.

⚖️  BIAS CHECK — WHO IS SAYING WHAT
Bejar	Has specific credibility as an insider with documented prior concerns; his 2021 letter establishes his account predates the litigation
States’ Attorneys General	His testimony is the most favorable development for the states’ case since opening arguments
Meta	Will challenge Bejar’s characterization; will argue the company did build safeguards despite what any individual engineer observed
Parents	Witnesses to testimony that directly names corporate knowledge of child harm; their presence gives the proceeding its human stakes

SOURCES

▸  NPR — Arturo Bejar testimony, Meta Oakland trial, August 20, 2026

▸  Bejar 2021 letter to Zuckerberg — established public record

Q: Who is Arturo Bejar?

A: He was a Meta engineer who worked on the company’s internal systems, including safety-related infrastructure. In 2021, he wrote directly to Mark Zuckerberg about safety concerns, using his own daughter’s Instagram harassment experience as a specific example. He subsequently left Meta. His testimony is insider rather than external precisely because of his prior engineering role.

Q: Does this testimony establish legal liability?

A: Testimony alone does not establish liability; it is evidence that the jury weighs against Meta’s counter-evidence. Bejar’s account establishes the knowledge element of the states’ theory; the causation element — connecting that knowledge to specific children’s deaths — requires additional evidence.