Meta CEO Mark Zuckerberg defended his social media companies Wednesday as he testified in a landmark trial, which will determine whether online platforms are designed to be addictive to children and young adults.

Zuckerberg took the stand during the unprecedented trial after Meta and Google, the parent company of YouTube, were accused of harming young users and targeting them to profit from them. The lawsuit was filed by a woman, identified only as K.G.M. alleged that social media use from an early age has led to addiction and caused depression and suicidal ideations.

The Meta CEO gave a tense and, at times, a combative testimony as he said preteens are barred from using his platforms. But he did admit that there are minors who break the rules to use them anyway.

Zuckerberg also told jurors that his company removes users who are found to be underage, suggesting it is up to users to read the terms.

He added his companies always had a goal for its product to be useful. And if it’s useful, people will likely use it more, he explained.

In response, the plaintiff’s attorney Mark Lanier replied, suggesting if it’s addictive, people will also use it more.

“The strategy for the plaintiffs attorney is that they are looking at a villain when they see a soft spoken, rich guy named Mark Zuckerberg, who from internal studies revealed children were at risk over this social media phenomenon, and yet, even though they had a few guardrails, they prioritized profits, over children’s mental health,” legal analyst Royal Oakes weighed in, while explaining Zuckerberg’s goal is to convince people that he’s not “some evil genius.”

“Instead, (Zuckerberg) recognizes that social media has an impact on people of all ages, and they’ve spent a lot of time, a lot of money setting up guardrails,” Oakes explained Meta’s potential approach in the trial. “The unspoken message is parents could have taken advantage of this, but a lot of them simply didn’t.”

Wednesday’s event was the first time Zuckerberg was questioned before a jury.

“(Zuckerberg) is the human representative of a gigantic corporation. Everything that’s been done by Meta comes down to how Zuckerberg can look into the eyes of a jury and explain, ‘No, we didn’t try to hurt kids, we don’t care just about profit,'” Oakes said.

Meta has maintained that it strongly contesting all allegations in K.G.M.’s lawsuit, and it is committed to the well-being of its young users.

As Zuckerberg walked into the LA courtroom, a group of parents, who said their children died due to social media, posed for a picture outside the courthouse. Some of them watched Zuckerberg’s testimony.

Last week, the head of Instagram, Adam Mosseri, defended the platform in court, also arguing that social media platforms are not intentionally engineered to be addictive.

The plaintiff has reached a settlement with Snapchat and TikTok.

The trial is being closely watched as a test case for hundreds of similar pending lawsuits. The cases all generally allege various damages from what attorneys call addictive social-media platforms powered by “complex algorithms designed to exploit human psychology.”

Some legal observers predict the trial’s outcome could have an influence on future social-media platform regulation and accountability.