Ex-Meta Engineer: Zuckerberg Chose Growth Not Child Safety

In an Oakland courtroom, a former Meta engineer painted a stark portrait of how decisions are made at the social giant: not in labs or committees, but at the top. Arturo Bejar told jurors that Mark Zuckerberg’s priorities shaped product choices across Facebook and Instagram, and safety for young users often lost out to engagement and growth.

Power, product design, and a culture that follows

Bejar, who worked at Meta from 2009 to 2015 and returned as a contractor between 2019 and 2021 to study teen welfare on Instagram, was the lead witness for the states in a high-stakes trial that could force major changes across the platforms. State attorneys say Meta engineered its apps to hook younger users, contributing to spikes in anxiety, depression, and even suicide, while obscuring what the company knew about those harms.

He described a top-down management style where a single executive’s focus could ripple through engineering teams: when Zuckerberg zeroed in on a metric, product work accelerated and design changes followed quickly. "If Mark prioritized something," Bejar testified, "mountains could be moved in months." Simple line. Huge implication.

That testimony directly challenged Zuckerberg’s public assurances that the company constantly uses research to make products safer. Bejar said he repeatedly raised concerns about child safety in emails to senior management, and he told jurors bluntly that trust in Zuckerberg on kids’ issues was misplaced.

The trial opened this week and is expected to run about six weeks. A jury will offer an advisory opinion, but it will be Judge Evan Gonzalez Rogers who ultimately rules on Meta’s liability and, if applicable, civil penalties and mandated product changes.

Not all evidence was abstract. Bejar recounted helping his teenage daughter set up an Instagram account. She was 16 at the time. He admitted during cross-examination that he did not foresee all the harms she might encounter. She joined to create a space for women to talk about cars and driving, but she ran into misogynistic comments and toxic interactions. "She gained followers," Bejar said, "but the price was harm." That line landed with the courtroom.

He also acknowledged that Meta employs hundreds of people in safety roles and that some are highly qualified. Still, Bejar said his second stint as an external contractor limited his access to internal resources and to Zuckerberg himself, making it harder to push for design changes from the outside.

One point of contention: Meta’s so-called break tools, which the company points to as evidence it helps users moderate their time. Bejar argued those features were set up to fail. They are not enabled by default, and their notifications are easy to ignore. From his perspective, the tools function more like public relations patches than systemic fixes.

He also testified that Meta had the technology to identify millions of likely under-13 users but chose a "don’t ask, don’t tell" approach, because stricter age enforcement could shrink long-term engagement and revenue. In short: the company traded potential safety measures for the economic benefits of broader user pools.

Recorded testimony from Meta researcher Elena Davis, played for the jury after Bejar finished, underlined the internal debate. Davis read from research suggesting Facebook could be redesigned to reduce habit-forming mechanics and help users break unwanted usage patterns. The research painted a very different product roadmap than the one critics say the company ultimately pursued.

Meta faces thousands of related lawsuits across the country. Bejar has been a witness in four separate trials against the company, and one earlier case filed by New Mexico resulted in a judgment requiring changes and awarding damages equivalent to about €876 million in penalties and costs.

So what’s at stake? Real reforms to how platforms are built. Or, alternatively, more incremental fixes that leave core engagement mechanics untouched. The jury’s advisory view and Judge Gonzalez Rogers’s eventual ruling will matter not just for Meta, but for how regulators and courts think about corporate responsibility in the attention economy.

If leadership prioritizes engagement above safety, product design will follow—intentionally or not.