Mark Zuckerberg set to testify in watershed social media trial

LOS ANGELES (AP) — Mark Zuckerberg will testify in an unprecedented social media trial that questions whether Meta's platforms deliberately addict and harm children.

Meta's CEO is expected to answer tough questions on Wednesday from attorneys representing a now 20-year-old woman identified by the initials KGM, who claims her early use of social media addicted her to the technology and exacerbated depression and suicidal thoughts. Meta Platforms and Google’s YouTube are the two remaining defendants in the case, which TikTok and Snap have settled.

Zuckerberg has testified in other trials and answered questions from Congress about youth safety on Meta's platforms, and he apologized to families at that hearing whose lives had been upended by tragedies they believed were because of social media. This trial, though, marks the first time Zuckerberg will answer similar questions in front of a jury. and, again, bereaved parents are expected to be in the limited courtroom seats available to the public.

The case, along with two others, has been selected as a bellwether trial, meaning its outcome could impact how thousands of similar lawsuits against social media companies would play out.

A Meta spokesperson said the company strongly disagrees with the allegations in the lawsuit and said they are “confident the evidence will show our longstanding commitment to supporting young people.”

One of Meta's attorneys, Paul Schmidt, said in his opening statement that the company is not disputing that KGM experienced mental health struggles, but rather that Instagram played a substantial factor in those struggles. He pointed to medical records that showed a turbulent home life, and both he and an attorney representing YouTube argue she turned to their platforms as a coping mechanism or a means of escaping her mental health struggles.

Zuckerberg's testimony comes a week after that of Adam Mosseri, the head of Meta's Instagram, who said in the courtroom that he disagrees with the idea that people can be clinically addicted to social media platforms. Mosseri maintained that Instagram works hard to protect young people using the service, and said it's “not good for the company, over the long run, to make decisions that profit for us but are poor for people’s well-being."

Much of Mosseri's questioning from the plaintiff's lawyer, Mark Lanier, centered on cosmetic filters on Instagram that changed people’s appearance — a topic that Lanier is sure to revisit with Zuckerberg. He is also expected to face questions about Instagram’s algorithm, the infinite nature of Meta’ feeds and other features the plaintiffs argue are designed to get users hooked.

Meta is also facing a separate trial in New Mexico that began last week.

Meta CEO Mark Zuckerberg arrives for a landmark trial over whether social media platforms deliberately addict and harm children, Wednesday, Feb. 18, 2026, in Los Angeles. (AP Photo/Ryan Sun)

Meta CEO Mark Zuckerberg arrives for a landmark trial over whether social media platforms deliberately addict and harm children, Wednesday, Feb. 18, 2026, in Los Angeles. (AP Photo/Ryan Sun)

Meta CEO Mark Zuckerberg arrives for a landmark trial over whether social media platforms deliberately addict and harm children, Wednesday, Feb. 18, 2026, in Los Angeles. (AP Photo/Ryan Sun)

Meta CEO Mark Zuckerberg arrives for a landmark trial over whether social media platforms deliberately addict and harm children, Wednesday, Feb. 18, 2026, in Los Angeles. (AP Photo/Ryan Sun)

Meta CEO Mark Zuckerberg arrives for a landmark trial over whether social media platforms deliberately addict and harm children, Wednesday, Feb. 18, 2026, in Los Angeles. (AP Photo/Ryan Sun)

Meta CEO Mark Zuckerberg arrives for a landmark trial over whether social media platforms deliberately addict and harm children, Wednesday, Feb. 18, 2026, in Los Angeles. (AP Photo/Ryan Sun)

Adam Mosseri, CEO of Instagram, arrives in court to testify in a landmark social media case that seeks to hold tech companies responsible for harms to children, Wednesday, Feb. 11, 2026, in Los Angeles. (AP Photo/Damian Dovarganes)

Adam Mosseri, CEO of Instagram, arrives in court to testify in a landmark social media case that seeks to hold tech companies responsible for harms to children, Wednesday, Feb. 11, 2026, in Los Angeles. (AP Photo/Damian Dovarganes)

Eight backcountry skiers were found dead and one remains missing after an avalanche near Lake Tahoe, authorities said Wednesday. The avalanche in Northern California's Sierra Nevada mountains is one of the deadliest in U.S. history. Here's a look at the others:

A massive wall of snow swept two Great Northern passenger trains into a gorge, killing 96 people. The trains had been stuck on the tracks for days because of bad weather, and some passengers had trekked into town, likely saving their lives.

In the most deadly event of the Klondike Gold Rush, a series of snow slides in April 1898 killed around 65 people on the Chilkoot Trail.

Ten climbers and a guide were killed by a massive ice avalanche on the Ingraham Glacier, the most deadly mountaineering accident in U.S. history.

An avalanche wiped out several homes in the town of Twin Lakes near Independence Pass, killing seven residents, including five children.

An avalanche crashed into the Alpine Meadows Ski Resort near Lake Tahoe, killing seven people, including four resort employees who remained on site even though the resort had been closed for the day because of the dangerous conditions. A 22-year-old chairlift operator was rescued five days later after a specially trained dog found her in the remains of the ski chalet.

FILE - Dave McClelland, a tour operator in Skagway, Alaska, tells the story of people killed in an 1898 avalanche along the Chilkoot trail now buried in a cemetery in the abandoned gold-rush town of Dyea, Alaska, on June 8, 1997. (AP Photo/Dave Germain, File)

This image provided by the Nevada County Sheriff's Office shows members of a rescue team in Soda Springs, California on Tuesday, Feb. 17, 2026. (Nevada County Sheriff's Office via AP)