Mark Zuckerberg testifies in landmark social media addiction trial

Mark Zuckerberg is testifying in a watershed social media trial that questions whether Meta's platforms are addictive and harm children.

Zuckerberg took the stand in Los Angeles Superior Court in the trial, marking his first time answering youth safety allegations before a jury.

He is also answering questions on Wednesday from lawyers representing the plaintiff, 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. 

FOX Business reported that a verdict for the plaintiff might set a precedent for holding tech companies accountable for harmful design decisions, despite years of invoking Section 230’s content liability shield, a federal law that largely shields online platforms from lawsuits related to user-posted content.

In the past, Zuckerberg has testified in other trials and answered questions from Congress about youth safety on Meta's social media platforms.

RELATED: Meta and YouTube facing landmark trial related to youth addiction claims

FILE-Mark Zuckerberg, CEO of Meta testifies before the Senate Judiciary Committee at the Dirksen Senate Office Building on January 31, 2024 in Washington, D.C. (Photo by Alex Wong/Getty Images)

Meta Platforms and Google’s YouTube are the two remaining defendants in the case, which TikTok and Snapchat have settled. In January 2026, TikTok agreed to the lawsuit before the trial started, the plaintiff’s attorneys confirmed to the Associated Press. 

TikTok was one of three companies — along with Meta’s Instagram and Google’s YouTube — facing claims that their platforms intentionally addict and harm children. A fourth company named in the lawsuit, Snapchat parent company Snap Inc., settled the case last week for an undisclosed amount of money.

Recently, a Meta spokesperson told the Associated Press that the company strongly disagrees with the accusations in the lawsuit and added they are "confident the evidence will show our longstanding commitment to supporting young people."

What is the Meta and YouTube trial about?

Dig deeper:

The trial involves a 19-year-old identified by the initials "KGM," whose case could determine how thousands of other, similar lawsuits against social media companies will play out.

KGM asserts that her use of social media from an early age addicted her to the technology and amplified depression and suicidal thoughts, according to the Associated Press.

RELATED: States file lawsuits against Meta over kids' mental health

This lawsuit also claims that this was done through intentional design choices made by tech organizations that sought to make their social media platforms more addictive to children to bolster their earnings. 

If this argument is successful, the AP noted that it would evade the organizations’ First Amendment protection, which safeguards tech companies from responsibility for content posted on their platforms. 

Tech companies respond to case

The other side:

Meta, TikTok, and YouTube refute the allegations that their social media platforms intentionally harm children, referencing protections they have added through the years, while contending that they are not accountable for content posted on their sites by third parties.

RELATED: Excessive social media use has many of the same effects as substance abuse, says expert

In a statement provided to the Associated Press, a Meta spokesperson said Monday that the organization strongly disagrees with the allegations outlined in the lawsuit and that it's "confident the evidence will show our longstanding commitment to supporting young people."

José Castañeda, a Google Spokesperson, told the AP Monday that the allegations against YouTube are "simply not true." In a statement, Castañeda said "Providing young people with a safer, healthier experience has always been core to our work."

Meanwhile, TikTok did not offer a comment on the case, the AP noted. 

Meta, TikTok, and YouTube facing additional lawsuits

Big picture view:

According to the Associated Press, over 40 state attorneys general have filed lawsuits against Meta, alleging it is harming children and contributing to the youth mental health crisis by intentionally creating features on Instagram and Facebook that can addict children to its social media platforms. Moreover, TikTok is also facing similar lawsuits in over a dozen states.