EFF's Guide To CDA 230: The Most Important Law Protecting Online Speech

In 1996, while debating the intricacies of a bill that would massively overhaul the telecommunications laws of the United States, two astute Congressmen introduced an amendment that would allow the Internet to flourish.

The amendment—which would become Section 230 of the Communications Decency Act (CDA 230)—stated that "No provider or user of an interactive computer service shall be treated as the publisher or speaker of any information provided by another information content provider." In other words, online intermediaries that host or republish speech—blogs, review sites, social networks, and more—are protected against a range of laws that might otherwise be used to hold them legally responsible for what others say and do.

CDA 230 is crucial to the free flow of expression online. While the rest of the Communications Decency Act, an attempt by the government to regulate indecent content online, was found unconstitutional by the courts, Section 230 survived. As Judge Wilkinson put it in the seminal CDA 230 case, Zeran v. America Online, "Section 230 was enacted, in part, to maintain the robust nature of Internet communication, and accordingly, to keep government interference in the medium to a minimum." Websites could edit, filter, and screen content if they wanted without being held liable for the content itself...