A landmark jury trial began in Los Angeles this week over whether Instagram and YouTube were designed to addict young users and harm their mental health. The plaintiff, identified as K.G.M., says the platforms worsened her depression and suicidal thoughts. The case, heard before Los Angeles County Superior Court Judge Carolyn B. Kuhl, could shape thousands of similar lawsuits pending nationwide.
Opening arguments set the stakes
Plaintiff’s lawyer Mark Lanier told jurors the companies built “addiction machines” aimed at children. He said internal documents will show intentional design choices that maximize time spent. Defense counsel countered that the plaintiff’s struggles trace to family turmoil and pre-existing issues, not product design. The trial is expected to last six to eight weeks.
What the plaintiff alleges
The complaint targets the design of feeds, alerts and autoplay. It argues these features encourage compulsive use and that the firms failed to warn young users. In court, Lanier referenced internal messages—including a 2015 email goal to raise “time spent” by 12%—to argue profit trumped safety. The defense disputes that interpretation.
How Meta and YouTube responded
Lawyers for Meta Platforms and for YouTube owner Google say the apps were not a substantial factor in K.G.M.’s harms. Meta’s attorney Paul Schmidt highlighted records of long-running family conflict and therapy that began in early childhood. The companies also point to youth-safety tools and argue they cannot be liable for third-party content, only for their own product design. Judge Kuhl instructed jurors on that distinction.
Why this case could set a benchmark
This is a bellwether trial—a case used to test evidence and legal theories that can influence settlement and strategy in many related suits. A verdict for the plaintiff could encourage more claims by families, school districts and states; a defense win could slow the wave. Top executives, including Mark Zuckerberg, Adam Mosseri and Neal Mohan, are expected to testify. Separately, Snap and TikTok settled with K.G.M. before trial and are no longer defendants.
What comes next in court
Jurors will hear expert testimony on adolescent mental health and product design, along with former employees who raised safety concerns. They will decide first on liability for design choices and warnings. If the jury finds liability, it may consider damages, including punitive awards. Proceedings are running alongside a separate New Mexico case against Meta and ahead of a federal bellwether set for later this year.
The Los Angeles trial tests where product design ends and user responsibility begins. Its outcome will send a signal to families, platforms and regulators on how far the law will go in policing the attention economy.
