A recent California court decision involving Section 230 of the Communications Decency Act (CDA) is creating considerable concern among social media companies and other website operators.

As we've discussed in past blog posts, CDA Section 230 has played an essential role in the growth of the Internet by shielding website operators from defamation and other claims arising from content posted to their websites by others.

Under Section 230, a website operator is not "treated as the publisher or speaker of any information provided" by a user of that website; as a result, online businesses such as Facebook, Twitter and YouTube have been able to thrive despite hosting UGC on their platforms that may be false, deceptive or malicious and that, absent Section 230, might subject these and other Internet companies to crippling lawsuits.

Recently, however, the California Court of Appeal affirmed a lower court opinion that could significantly narrow the contours of Section 230 protection. After a law firm sued a former client for posting defamatory reviews on Yelp.com, the court not only ordered the former client to remove the reviews, but demanded that Yelp (which was not party to the dispute) remove these reviews.

The case, Hassell v. Bird, began in 2013 when attorney Dawn Hassell sued former client Ava Bird regarding three negative reviews that Hassell claimed Bird had published on Yelp.com under different usernames. Hassell alleged that Bird had defamed her, and, after Bird failed to appear, the California trial court issued an order granting Hassell's requested damages and injunctive relief.

In particular, the court ordered Bird to remove the offending posts, but Hassell further requested that the court require Yelp to remove the posts because Bird had not appeared in the case herself. The court agreed, entering a default judgment and ordering Yelp to remove the offending posts. (The trial court also ordered that any subsequent comments associated with Bird's alleged usernames be removed, which the Court of Appeal struck down as an impermissible prior restraint.) Yelp challenged the order on a variety of grounds, including under Section 230.

The Court of Appeal held that the Section 230 safe harbor did not apply and that Yelp could be forced to comply with the order. The court reasoned that the order requiring Yelp to remove the reviews did not impose any liability on Yelp; Yelp was not itself sued for defamation and had no damages exposure, so Yelp did not face liability as a speaker or publisher of third-party speech. Rather, citing California law that authorized a court to prevent the repetition of "statements that have been adjudged to be defamatory," the court characterized the injunction as "simply" controlling "the perpetuation of judicially declared defamatory statements." The court acknowledged that Yelp could face liability for failing to comply with the injunction, but that would be liability under the court's contempt power, not liability as a speaker or publisher.

The Hassell case represents a significant setback for social media companies, bloggers and other website operators who rely on the Section 230 safe harbor to shield themselves from the misconduct of their users. While courts have previously held that a website operator may be liable for "contribut[ing] materially to the alleged illegality of the conduct"--such as StubHub.com allegedly suggesting and encouraging illegally high ticket resale prices--here, in contrast, there is no claim that Yelp contributed to or aided in the creation or publication of the defamatory reviews, besides merely providing the platform on which such reviews were hosted.

Of particular concern for online businesses is that Hassell appears to create an end-run around Section 230 for plaintiffs who seek to have allegedly defamatory or false UGC removed from a website: sue the suspected posting party and, if that party fails to appear, obtain a default judgment; with a default judgment in hand, seek a court order requiring the hosting website to remove the objectionable post, as the plaintiff was able to do in the Hassell case.

Commentators have observed that Hassell is one of a growing number of recent decisions seeking to curtail the scope of Section 230. After two decades of expansive applications of Section 230, are we now on the verge of a judicial backlash against the law that has helped to fuel the remarkable success of the U.S. Internet industry?