Social media companies are bracing for Supreme Court arguments on Monday that could fundamentally alter the way they police their sites.

After Facebook, Twitter and YouTube barred President Donald J. Trump in the wake of the Jan. 6, 2021, riots at the Capitol, Florida made it illegal for technology companies to ban from their sites a candidate for office in the state. Texas later passed its own law prohibiting platforms from taking down political content.

Two tech industry groups, NetChoice and the Computer & Communications Industry Association, sued to block the laws from taking effect. They argued that the companies have the right to make decisions about their own platforms under the First Amendment, much as a newspaper gets to decide what runs in its pages.

So what’s at stake?

The Supreme Court’s decision in those cases — Moody v. NetChoice and NetChoice v. Paxton — is a big test of the power of social media companies, potentially reshaping millions of social media feeds by giving the government influence over how and what stays online.

“What’s at stake is whether they can be forced to carry content they don’t want to,” said Daphne Keller, a lecturer at Stanford Law School who filed a brief with the Supreme Court supporting the tech groups’ challenge to the Texas and Florida laws. “And, maybe more to the point, whether the government can force them to carry content they don’t want to.”

If the Supreme Court says the Texas and Florida laws are constitutional and they take effect, some legal experts speculate that the companies could create versions of their feeds specifically for those states. Still, such a ruling could usher in similar laws in other states, and it is technically complicated to accurately restrict access to a website based on location.