Oakland, California - Meta knowingly hooked and exploited children, a federal court heard Tuesday in the trial of the social media giant on charges that it deliberately made Instagram and Facebook addictive to young users.

In what many experts have called social media's "big tobacco moment," a coalition of states is demanding Meta pay $200 billion in penalties for using technology specifically designed to foster addiction among children in a similar fashion to cigarettes.

Meta "exploited how kids' brains work," California prosecutor Megan O'Neill said in opening arguments, painting Meta's business model as one built to "hook the users, hold them for as long as they can, harvest their data, and then hide the truth from the public."

Meta's lawyer, Paul Schmidt, acknowledged that some users were harmed by the networks, but argued that the company had "tried to come up with tools to help them."

Before the trial began, the company denied all the allegations, insisting it had worked with parents, experts, and law enforcement to incorporate protective safeguards for children.

This is not the first case seeking to hold tech companies – including Meta – accountable for these types of issues, but it could become one of the most consequential if it leads to sweeping changes on the platforms.

Meta founder and chief Mark Zuckerberg is among the star witnesses expected to testify, along with Instagram head Adam Mosseri.

Activists, including mothers of children they say were driven to suicide by their social media usage, rallied outside the court.

One mother, Lori Schott, called out Zuckerberg and Mosseri, saying they "built one of those most powerful and richest companies in the world... But power does not excuse harm."

If you or someone you know needs help, please contact the 24-hour National Suicide Prevention Hotline by calling or texting 988 for free and confidential support. You can also text "HOME" to 741741 anytime for the Crisis Text Line and access to live, trained crisis counselors.