For decades, social media companies have operated under the protection of a powerful legal shield.

If something harmful shows up on their platforms, like harassment or dangerous content, the companies themselves aren't liable.

That shield made social media giants virtually untouchable in court, until last week.

In a Los Angeles courtroom, a 20-year-old woman took on meta and YouTube.

She claimed that the platforms harmed her mental health.

And she won, not by breaking through the shield,

but by going around it. This case took a totally different route.

Our colleague Aaron Mulvaney covers legal affairs. In this case, she says, didn't focus on the

content on these platforms. It focused on how the platforms were made.

The way they designed the products, so that would be the algorithms used to attract people,

things we know about like the infinite scroll or notifications that can lead to dopamine hits for kids and things like that.

And the plaintiff's argument was simple. If a product's design can cause harm, the platform

maker should be held responsible. I think it was a creative theory. It hadn't really been

tested before. Right. Until this verdict. What could this

outcome mean for meta and YouTube? That could mean that these companies will be forced to look at how

they design their products, how they operate. And for us, that would mean how we interact with it

and how we use it. So this is sort of

just the beginning? I think it's the beginning. I mean, this was a loss and they're going to have

to think about what down the line this could mean for their products. Welcome to the Journal,

our show about money, business, and power.

I'm Jessica Mendoza.

It's Monday, March 30th.

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