By Diana Novak Jones and Jonathan Stempel
Aug 25 (Reuters) - Instagram's chief executive, Adam Mosseri, is expected to take the witness stand on Tuesday in a trial over whether Meta Platforms designed Instagram and Facebook to addict children without proper regard for their safety.
Mosseri is a central witness in the lawsuit by 29 U.S. states, in what experts call the biggest legal test yet of social media's effects on young users.
Four of the states — California, Colorado, Kentucky and New Jersey — have
accused Meta of designing the platforms to hook young users, fueling anxiety, depression and even suicide, while misleading consumers about their safety.
All 29 states say Meta violated federal law by improperly collecting and using personal data of children under 13 while they used its platforms.
The states have indicated they could seek nearly $200 billion in civil penalties.
Meta has rejected accusations it sought to addict children in pursuit of profit, and said its research showed no clear link between adolescents' social media use and a lack of well-being.
The expected testimony by Mosseri was confirmed by the office of California Attorney General Rob Bonta.
Mosseri became Instagram's chief in 2018.
In February, Mosseri testified in a Los Angeles trial where a jury ordered Meta and Alphabet's Google to pay $6 million to a 20-year-old woman who said she became addicted to Instagram and YouTube as a child. Jurors found Meta and Google negligent in designing their platforms.
Mosseri disputed suggestions that Instagram did not care about children's safety, and defended its design choices against accusations by company insiders that its features were harmful. He said Instagram's products and policies evolve, and "we try to focus on the most important issues."
Earlier this month, a New Mexico judge ordered Meta to pay $567 million to address teenagers' mental health after that state's attorney general called its platforms a public nuisance.
Tennessee is also suing Meta, raising similar claims about Instagram, in a case on trial in Nashville.
(Reporting by Diana Novak Jones in Chicago and Jonathan Stempel in New York; Additional reporting by Nathan Frandino in Oakland, California; Editing by Matthew Lewis)
