Explainer: Just why are social media companies on trial

In a wood-panelled courtroom in Los Angeles, a legal battle is unfolding that many experts are calling the “Big Tobacco moment” of the 21st century.

The trial, which began yesterday (February 9th 2026), sees the world’s most powerful social media giants facing a jury to decide whether they intentionally built “addiction machines” that compromised the mental health of a generation.

This landmark case, brought by a plaintiff identified as Kaley G.M, centres on the allegation that platforms such as Instagram and YouTube are not neutral tools, but instead engineered products designed to exploit the developing brains of children.

The central argument presented by lead counsel Mark Lanier is that these companies prioritized corporate growth over child safety. By using a display of children’s blocks to illustrate the “ABC” of the case, Addicting Brains of Children, Lanier argued that features like infinite scroll and autoplay were deliberate design choices meant to keep young users hooked.

To support this, the prosecution has brought forward internal documents, including a 2015 email from Meta CEO Mark Zuckerberg demanding a 12% increase in time spent on the platform. The trial draws a direct parallel to the tobacco litigation of the 1990s, suggesting that just as cigarette manufacturers manipulated nicotine to ensure addiction, tech companies manipulated algorithms to achieve the same result.

Snapchat and TikTok settle

While Meta and YouTube both remain in the dock, they are standing alone among the original giants named in the suit. Last month, both Snapchat and TikTok settled with the plaintiff for undisclosed sums, opting to avoid the public spectacle and the risk of a jury verdict.

In contrast, Meta and Google have mounted a vigorous defence, shifting the focus from their algorithms to the plaintiff’s personal life. Meta’s attorneys have pointed to records of domestic turmoil and family distress, arguing that these external factors – rather than social media usage – were the primary cause of Kaley’s psychological struggles.

They maintain that under federal law, they are not responsible for how third parties use their platforms or for the personal circumstances of their users.

The outcome of this six-week trial will serve as a critical benchmark for thousands of similar cases currently pending across the United States. If the jury finds these companies liable, it could trigger a massive wave of monetary damages and force a radical redesign of the digital world.

Beyond the courtroom, state attorneys general are already pushing for court orders that would require Meta to disable addictive features, delete data on users under 13, and implement strict time restrictions.

With testimony expected from high-ranking executives, including Meta’s Mark Zuckerberg and YouTube CEO Neal Mohan, the proceedings represent a historic reckoning.

For the parents standing outside the courthouse holding photos of children they lost to social media-related harms, the trial is a long-awaited attempt to hold “Big Tech” accountable for the design of its virtual world.