The major social media trial unfolding in L.A. this week

LOS ANGELES, Calif. -- A landmark social media trial is unfolding in a Los Angeles courtroom this week.

It focuses on claims against Meta, which owns Instagram and Facebook, as well as YouTube, owned by Google. It alleges that some social media platforms were knowingly designed to make kids and teens addicted to them.

Meta CEO Mark Zuckerberg took the stand on Wednesday and was questioned by the plaintiff's lawyer.

The lawsuit was brought by a woman, now 20 years old, and her mom, who say she was exposed to addictive features on these social media platforms as a child. Her lawyers say those features led to anxiety, depression, and body image issues.

This case has drawn attention to a longtime legal shield, which has protected social media platforms in the past.

South Bend attorney Frank Julian explains how the plaintiffs in this case are trying to circumvent that immunity.

“What they're arguing is that Facebook and Instagram are products that are defective as used, and they're doing this in order to try to get around what's known as Section 230 of the Communications Decency Act, which has in the past provided a lot of protection to social media platforms and internet sites like YouTube and Facebook and so it's a complicated case,” said Julian.

Julian says the companies are arguing their products are not defective, and they say the plaintiffs are blaming social media companies for other mental health problems teenagers can have.

The companies say they've also implemented safeguards to protect younger users.

This case is the first of more than 1500 lawsuits similar to it to go before a jury. This could, in turn, set a precedent for holding tech companies liable for the way their products are designed.