A landmark legal battle against major social media giants Meta and YouTube formally began on Monday in a Los Angeles civil court, a case that could redefine how technology companies are held accountable for the wellbeing of young users across the United States.
At the heart of the lawsuit is the question of whether social media platforms deliberately design their products to be addictive for children and teenagers. Legal experts say the outcome may set a powerful precedent for future regulation and litigation involving digital platforms.
The case was filed by a 20-year-old woman identified as Kayley GM, who claims she suffered long-term psychological harm after developing a compulsive dependence on social media during her childhood. The proceedings are being overseen by Judge Carolyn Kuhl.
During opening arguments, the plaintiff’s attorney, Mark Lanier, accused Meta and YouTube of knowingly creating features that keep young users constantly engaged. He argued that these platforms were engineered to maximize screen time, not by accident, but as part of a profit-driven strategy.
Lanier told the jury that Instagram’s endless scrolling and social validation loops push children to seek approval through likes and comments. He also highlighted YouTube’s autoplay system, which automatically queues similar videos based on user behavior, making it difficult for young viewers to disengage.
According to the lawyer, internal documents and scientific research will be presented to demonstrate how these digital features influence brain development. He emphasized that children and adolescents are particularly vulnerable to such persuasive design techniques.
The trial is expected to feature high-profile testimony. Meta CEO Mark Zuckerberg is likely to be called as a witness, while YouTube chief executive Neil Mohan and Instagram head Adam Mosseri may also appear before the court.
The case is being closely monitored nationwide, as hundreds of similar lawsuits accusing social media platforms of contributing to depression, anxiety, eating disorders, self-harm, and even suicide are already pending. Legal teams are reportedly using strategies similar to those once employed in lawsuits against tobacco companies.
Meta and YouTube have strongly denied the allegations. A spokesperson for YouTube stated that the claims are unfounded and insisted that the company prioritizes the safety and wellbeing of young users.
Both companies also argue that Section 230 of US law protects them from liability related to user content. However, the court will now examine whether platform design and algorithmic choices create legal responsibility beyond content hosting.
Other platforms, including Snapchat and TikTok, were initially named in the lawsuit but reached settlements before the trial began. The terms of those agreements have not been made public.
