The Supreme Court seemed skeptical on Monday of laws in Florida and Texas that bar major social media companies from making editorial judgments about which messages to allow.
The laws were enacted in an effort to shield conservative voices on the sites, but a decision by the court, expected by June, will almost certainly be its most important statement on the scope of the First Amendment in the internet era, with broad political and economic implications.
A ruling that tech platforms have no editorial discretion to decide which posts to allow would expose users to a greater variety of viewpoints but almost certainly amplify the ugliest aspects of the digital age, including hate speech and disinformation.
Though a ruling in favor of big platforms like Facebook and YouTube appeared likely, the court also seemed poised to return the cases to the lower courts to answer questions about how the laws apply to sites that do not seem to moderate their users’ speech in the same way, like Gmail, Venmo, Uber and Etsy.
The justices differed about whether the laws, which have been blocked for now, should go into effect in the meantime. But a majority seemed inclined to keep them on hold while the litigation moves forward. Several justices said that the states violated the First Amendment by telling a handful of major platforms that they could not moderate their users’ posts, drawing distinctions between government censorship prohibited by the First Amendment and actions by private companies to determine what speech to include on their sites.
“I have a problem with laws that are so broad that they stifle speech just on their face,” Justice Sonia Sotomayor said.
Justice Brett M. Kavanaugh read a sentence from a 1976 campaign finance decision that has long been a touchstone for him. “The concept that government may restrict the speech of some elements of our society in order to enhance the relative voice of others is wholly foreign to the First Amendment,” he said, indicating that he rejected the states’ argument that they may regulate the fairness of public debate in private settings.
“I wonder,” Chief Justice John G. Roberts Jr. said, “since we’re talking about the First Amendment, whether our first concern should be with the state regulating what, you know, we have called the modern public square.”
Henry C. Whitaker, Florida’s solicitor general, responded that “the state has an interest, a First Amendment interest, in promoting and ensuring the free dissemination of ideas.”
Justice Elena Kagan said the major platforms had good reasons to reject posts inciting insurrection, endangering public health and spreading hate speech. “Why isn’t that a First Amendment judgment?” she asked.
The court’s three most conservative members — Justices Clarence Thomas, Samuel A. Alito Jr. and Neil M. Gorsuch — seemed sympathetic to the state laws. All three said phrases like “content moderation” were euphemisms for censorship.
When the discussion turned to less prominent sites, the justices across the ideological spectrum were troubled by the lack of information about them in the record before the court. Several indicated that they might analyze the First Amendment question differently depending on the platform.
Justice Kagan asked whether states could tell services like Venmo, Dropbox and Uber that they may not discriminate on the basis of their users’ viewpoints.
“Wouldn’t that be all right?” she asked Paul D. Clement, a lawyer for the challengers.
Mr. Clement said no, responding that all of those services “are still in the expressive business,” meaning that speech is part of their core activities in ways not true of, say, a gas station or ice cream stand.
Other justices asked about email and messaging services.
“Does Gmail have a First Amendment right to delete, let’s say, Tucker Carlson’s or Rachel Maddow’s Gmail accounts if they don’t agree with his or her viewpoints?” Justice Alito asked Mr. Clement.
Mr. Clement responded that the service “might be able to do that,” adding that such questions had not been the focus of the litigation.
He added that forbidding the platforms to make distinctions based on viewpoint would destroy their businesses.
“If you have to be viewpoint-neutral,” he said, “that means that if you have materials that are involved in suicide prevention, you also have to have materials that advocate suicide promotion. Or, if you have materials on your site that are pro-Semitic, then you have to let on materials onto your site that are antisemitic. And that is a formula for making these websites very unpopular to both users and advertisers.”
The laws’ supporters said they were an attempt to combat what they called Silicon Valley censorship, through which major social media companies had deleted posts expressing conservative views. The laws were prompted in part by the decisions of some platforms to bar President Donald J. Trump after the Jan. 6, 2021, attack on the Capitol.
The laws, from Florida and Texas, differ in their details. Florida’s prevents the platforms from permanently barring candidates for political office in the state, while Texas’ prohibits the platforms from removing any content based on a user’s viewpoint.
“To generalize just a bit,” Judge Andrew S. Oldham wrote in a decision upholding the Texas law, the Florida law “prohibits all censorship of some speakers,” while the one from Texas “prohibits some censorship of all speakers” when based on the views they express.
The two trade associations challenging the state laws — NetChoice and the Computer & Communications Industry Association — said that the actions Judge Oldham called censorship were editorial choices protected by the First Amendment, which generally prohibits government restrictions on speech based on content and viewpoint.
The groups said that social media companies were entitled to the same constitutional protections enjoyed by newspapers, which are generally free to publish what they like without government interference.
Justice Kavanaugh appeared to embrace that position, asking Mr. Whitaker, the lawyer representing Florida, whether states could tell publishing houses, printing presses, movie theaters, bookstores and newsstands what to feature.
Mr. Whitaker said that newspapers and bookstores are engaged in “inherently expressive conduct,” while “our whole point is that these social media platforms are not like those.”
He said that, indeed, the platforms were common carriers required to transmit everyone’s messages and that the Florida law protected free speech by ensuring that users have access to many points of view.
Several justices said it was hard to reconcile the platforms’ arguments on Monday with what they had said last year in cases concerning Section 230 of the Communications Decency Act, which protects social media companies from liability for what their users post.
In those cases, Justice Thomas said, the platforms maintained that they were merely conduits for others’ speech. “Now you’re saying that you are engaged in editorial discretion and expressive conduct,” he told Mr. Clement. “Doesn’t that seem to undermine your Section 230 arguments?”
Mr. Clement responded that a key part of the provision was meant to protect platforms from liability for making editorial judgments
Federal appeals courts reached conflicting conclusions in 2022 about the constitutionality of the two laws.
A unanimous three-judge panel of the U.S. Court of Appeals for the 11th Circuit largely upheld a preliminary injunction blocking Florida’s law.
“Social media platforms exercise editorial judgment that is inherently expressive,” Judge Kevin C. Newsom wrote for the panel. “When platforms choose to remove users or posts, deprioritize content in viewers’ feeds or search results or sanction breaches of their community standards, they engage in First Amendment-protected activity.”
But a divided three-judge panel of the Fifth Circuit reversed a lower court’s order blocking the Texas law.
“We reject the platforms’ attempt to extract a freewheeling censorship right from the Constitution’s free speech guarantee,” Judge Oldham wrote for the majority. “The platforms are not newspapers. Their censorship is not speech.”
The Biden administration supported the social media companies in the two cases, Moody v. NetChoice, No. 22-277, and NetChoice v. Paxton, No. 22-555.
The Supreme Court blocked the Texas law in 2022 while the case moved forward by a 5-to-4 vote.
Justice Alito wrote that the issues were so novel and significant that the Supreme Court would have to consider them at some point. He added that he was skeptical of the argument that the social media companies have editorial discretion protected by the First Amendment the way newspapers and other traditional publishers do.
“It is not at all obvious,” he wrote, “how our existing precedents, which predate the age of the internet, should apply to large social media companies.”
