Meta CEO Mark Zuckerberg appeared Wednesday at the Los Angeles Superior Court to testify in the landmark social media addiction trial. The case alleges that Meta and YouTube intentionally designed features on Facebook, Instagram, and YouTube to be addictive, harming children’s mental health.

Axar.az reports, citing CNN, that the lawsuit, brought by a young woman identified as “Kaley” and her mother, claims that prolonged exposure to these platforms from ages 6–9 caused anxiety, body dysmorphia, suicidal thoughts, and exposure to bullying and sextortion. Kaley’s case is the first of over 1,500 similar lawsuits.

Zuckerberg is defending Meta’s efforts to protect minors, citing safety tools such as parental oversight, teen accounts, privacy defaults, and content restrictions. Meta argues that Kaley’s mental health struggles stemmed from family circumstances rather than social media.

The trial will examine whether Instagram and other platforms were a substantial factor in the plaintiff’s mental health issues, and whether Meta prioritized profits over youth safety. Experts note that Zuckerberg’s demeanor and testimony could significantly influence the jury’s perception.