In a recent Supreme Court brief, lawyers for Texas said the challenged law does not affect the platforms’ free speech rights because “no reasonable viewer could possibly attribute what a user says to the platforms themselves.” The brief added: “Given the platforms’ virtually unlimited capacity to carry content, requiring them to provide users equal access regardless of viewpoint will do nothing to crowd out the platforms’ own speech.”

In an earlier brief, the state’s lawyers wrote that “the platforms are the 21st century descendants of telegraph and telephone companies: that is, traditional common carriers.” That means, they wrote, that the companies must generally accept all customers.

The Biden administration filed a brief in August urging the justices to hear the cases — Moody v. NetChoice, No. 22-277, and NetChoice v. Paxton, No. 22-555 — and to rule in the companies’ favor.

“When a social-media platform selects, edits and arranges third-party speech for presentation to the public, it engages in activity protected by the First Amendment,” Solicitor General Elizabeth B. Prelogar wrote for the administration, adding that “the act of culling and curating the content that users see is inherently expressive, even if the speech that is collected is almost wholly provided by users.”