PHIL HAMBURGER: The Constitution Can Crack Section 230: Tech companies think the statute allows them to censor with impunity. The law is seldom so simple.

Section numbers of federal statutes rarely stir the soul, but one of them, 230, stirs up much fear, for it has seemed to justify censorship. Relying on it, tech companies including Google and Twitter increasingly pull the plug on disfavored posts, websites and even people. Online moderation can be valuable, but this censorship is different. It harms Americans’ livelihoods, muzzles them in the increasingly electronic public square, distorts political and cultural conversations, influences elections, and limits our freedom to sort out the truth for ourselves.

But does the 1996 Communications Decency Act really justify Big Tech censorship? The key language, Section 230(c)(2), provides: “No provider or user of an interactive computer service shall be held liable on account of . . . any action voluntarily taken in good faith to restrict access to or availability of material that the provider or user considers to be obscene, lewd, lascivious, filthy, excessively violent, harassing, or otherwise objectionable, whether or not such material is constitutionally protected.” The companies take this as a license to censor with impunity.

That understanding is questionable. Law is rarely as clear-cut as a binary switch. To be sure, courts emphasize the breadth of Section 230’s immunity for website operators. But there is little if any federal appellate precedent upholding censorship by the big tech companies. The question therefore comes down to the statute itself. The answers should give pause to the companies and courage to those they’ve censored. . . .

That doesn’t necessarily mean Section 230 is unconstitutional. But when a statute regulating speech rests on the power to regulate commerce, there are constitutional dangers, and ambiguities in the statute should be read narrowly.

A second constitutional question arises from the First Amendment. The companies brush this aside because they are private and the amendment prohibits only government censorship. Yet one must worry that the government has privatized censorship. If that sounds too dramatic, read Section 230(c)(2) again. It protects tech companies from liability for restricting various material “whether or not such material is constitutionally protected.” Congress makes explicit that it is immunizing companies from liability for speech restrictions that would be unconstitutional if lawmakers themselves imposed them.

Seventeenth-century censorship, which the First Amendment clearly prohibited, was also imposed largely through private entities, such as universities and the Stationers’ Company, England’s printers trade guild. Whereas privatized censorship then was often mandatory, the contemporary version is voluntary. But the tech companies are protected for restricting Congress’s list of disfavored materials, and this means that the government still sets the censorship agenda.

Some of the material that can be restricted under Section 230 is clearly protected speech. Consider its enumeration of “objectionable” material. The vagueness of this term would be enough to make the restriction unconstitutional if Congress directly imposed it. That doesn’t mean the companies are violating the First Amendment, but it does suggest that the government, in working through private companies, is abridging the freedom of speech.

This constitutional concern doesn’t extend to ordinary websites that moderate commentary and comments; such controls are their right not only under Section 230 but also probably under the First Amendment. Instead, the danger lies in the statutory protection for massive companies that are akin to common carriers and that function as public forums. The First Amendment protects Americans even in privately owned public forums, such as company towns, and the law ordinarily obliges common carriers to serve all customers on terms that are fair, reasonable and nondiscriminatory. Here, however, it is the reverse. Being unable to impose the full breadth of Section 230’s censorship, Congress protects the companies so they can do it.

Some Southern sheriffs, long ago, used to assure Klansmen that they would face no repercussions for suppressing the speech of civil-rights marchers. Under the Constitution, government cannot immunize powerful private parties in the hope that they will voluntarily carry out unconstitutional policy.

Well, the Klan served as Democratic enforcers then. Facebook does the job now.