A group of four states faced off against Meta in a high-profile trial in California on Tuesday, accusing the tech giant of hooking young users on its social media sites and misleading the public about the risks.

California, Colorado, Kentucky and New Jersey are part of a coalition of 29 states suing the company for allegedly designing features to keep kids on Facebook and Instagram and deceiving parents about the safety of their platforms.

“Meta hooked kids on its platforms by taking advantage of how their brains work,” Megan O’Neill, deputy attorney general with the California Department of Justice, said in opening arguments Tuesday.

“Meta held onto those kids because it needed them to make money in the long [run],” she continued. “Meta harvested kids’ data, tracked their behavior, sent them ads to keep them hooked. And Meta hid the truth to keep the cycle going.”

The social media company argues the states’ allegations are unsubstantiated and an attempt to penalize the firm for issues that have plagued the whole industry, such as age verification.

“It’s a challenge across the entire industry,” Paul Schmidt, a lawyer representing Meta, said Tuesday.

He urged the jury to “keep an open mind and wait for the full evidence” as both sides make their case.

The trial, which is expected to last six weeks, marks the latest in a series of legal challenges against Meta and other social media giants over their handling of kids’ online safety.

Tech companies have largely been shielded from lawsuits over the years by Section 230, which prevents them from being held liable for third-party content posted on their websites.

A spate of recent cases seeks to sidestep this statute, instead taking aim at how the platforms are designed. O’Neill argued Tuesday that the states are not seeking to hold Meta responsible for actions by “bad people.”

“We are holding Meta responsible for its own conduct, what Meta did and didn’t say, what Meta did and didn’t do, the choices that Meta [made],” she said.

The states are reportedly seeking roughly $200 billion in damages, though Meta has portrayed in court documents that penalties could theoretically reach upwards of $1.4 trillion.

Meta CEO Mark Zuckerberg and Instagram head Adam Mosseri are expected to testify, along with current and former employees, executives and industry experts.

The company had sought to bar testimony from whistleblower Arturo Bejar, a former senior engineering and product leader at Facebook, by alleging that he allowed Signal chats with other former employees to auto-delete despite court orders that those records be preserved.

Meta asked that Bejar be sanctioned and not be allowed to take the stand, but the judge denied the request, calling it a “Hail Mary” attempt to “eliminate a strong witness” for the states.

Bejar, the states’ first called witness, testified on Tuesday that Meta has adopted a “don’t ask, don’t tell” approach to underage users on their platforms.

The latest court battle comes on the heels of several losses for the company.

A California jury found in March that Meta and YouTube were negligent in their design or operation of their platforms, ordering the companies to pay a combined $6 million. Meta is also facing a total of $942 million in fines in New Mexico, where a jury found it violated the state’s Unfair Practices Act.

Meta separately opted to settle a social media addiction case with a Kentucky school district in May, just weeks before it was set to head to trial. A minor who was suing the company in Los Angeles also dropped his case last month, after settling with the three other defendants — YouTube, TikTok and Snapchat.