Official Censorship Should Have No Place in the Digital Public Square

When officials and agencies use interactive social media in these ways, they create spaces that play important functions in our democracy. Their accounts can be sources of official information, channels through which citizens can petition their representatives for “redress of grievances” (as the First Amendment puts it) and forums in which citizens can exchange information and ideas. The same reasoning that led the appeals court to hold that Mr. Trump couldn’t constitutionally block critics from his Twitter account makes clear that other government actors who engage in similar conduct do so at their peril.

In fact, since we filed the case, almost a dozen other courts have applied the First Amendment’s public forum doctrine in cases involving the social media accounts of legislators, mayors, city councilors and sheriffs. The effect of these judicial rulings extends beyond the litigants. Made aware of these rulings, many public officials who were excluding people from their accounts based on viewpoint have voluntarily changed their practices.

These rulings also have implications for government-run accounts on platforms other than Twitter. The Army and Navy have been using Twitch, a gaming platform, to livestream e-sports as part of their recruiting efforts. Those who watch these multiplayer video games on the military’s Twitch channels can also exchange messages in moderated forums. The exchanges can be wide-ranging, but until recently moderators made a practice of ejecting participants who asked questions about war crimes. Moderators changed course only after the court’s decision in Mr. Trump’s case was brought to their attention.

These developments in the law, and in the practice of government agencies and officials, should be welcomed. The technology may be new, but the rule that government actors can’t exclude people from public forums on the basis of viewpoint has been practically synonymous with the First Amendment for decades. It’s a good thing that speakers who were previously silenced can now voice their dissent, that public officials who were previously shielded from the views of their constituents are now exposed to them and that digital forums that were previously echo chambers are now more ideologically diverse.

Over the next years, the courts, legislatures and the public will have to answer a slew of thorny questions about free speech and social media, including about the extent of Congress’s power to regulate the companies. As Justice Clarence Thomas noted Monday in connection with the Supreme Court’s order, some of these questions were presented starkly by the major social media companies’ decision to deplatform Mr. Trump after the siege on the Capitol. In comparison with these questions, the one presented by our case was easy.

But if the proposition that government officials may not exclude speakers from public forums because of their political views is straightforward, it’s also foundational to our democracy. Even those disinclined to thank Mr. Trump for anything can perhaps thank him for having given the courts an occasion to reaffirm this basic principle.

Jameel Jaffer is the executive director of the Knight First Amendment Institute at Columbia University. Katie Fallow is a senior staff attorney at the institute.

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