California jury finds Meta, YouTube liable in social media addiction trial

The jury answered yes to all seven questions on verdict forms for both companies, finding that Meta and YouTube were negligent in the design and operation of their platforms and that their negligence was a substantial factor in causing harm to the plaintiff.

Jurors also found that both companies knew or should have known their services posed a danger to minors, that they failed to adequately warn users of that danger, and that a reasonable platform operator would have done so.

"Accountability has arrived," lawyers for the plaintiff said in a statement.

A spokesman for Meta said they "respectfully disagree" with the verdict.

The panel assigned Meta 70 per cent of the responsibility for the plaintiff's harm -- a $2.1 million share of the compensatory award -- and YouTube the remaining 30 per cent, or $900,000.

Jurors further found that both companies had acted with malice, oppression or fraud, a finding that sets the stage for a separate punitive damages phase.

The plaintiff, known in court documents by her initials K.G.M. and identified as just Kaley at trial, is the central figure in a bellwether case that could determine whether social media companies can be held legally responsible for harming children's mental health.

Kaley began using YouTube at six, downloading the app on her iPod Touch to watch videos about lip gloss and an online kids game. She joined Instagram at nine, getting around a block her mother had put in place to keep her off the platform.

She told jurors that her near-constant social media use "really affected my self-worth," saying the apps led her to abandon hobbies, struggle to make friends and constantly measure herself against others.

In closing arguments, plaintiff attorney Mark Lanier cast the case as a story of corporate greed. He argued that features including infinite scrolling, autoplay videos, notifications and like counts were engineered to drive compulsive use among young people.

Meta and YouTube had maintained throughout that Kaley's mental health struggles had nothing to do with their platforms.

Meta lawyer Paul Schmidt highlighted her turbulent relationship with her mother, playing jurors a recording that appeared to capture her mother yelling and cursing at her.

YouTube disputed how much time Kaley actually spent on its platform, with its attorney telling the court that usage records showed she averaged little more than a minute a day on the very features her lawyers called addictive.

The jury rejected both defenses across all seven questions on each verdict form.