Twitter v. Taamneh and the Law & Economics of Intermediary Liability

Cite this Article
Geoffrey A. Manne, Kristian Stout and Ben Sperry, Twitter v. Taamneh and the Law & Economics of Intermediary Liability, Truth on the Market (March 08, 2023), https://truthonthemarket.com/2023/03/08/twitter-v-taamneh-and-the-law-economics-of-intermediary-liability/

The Senate Judiciary Committee’s Subcommittee on Privacy, Technology, and the Law will host a hearing this afternoon on Gonzalez v. Google, one of two terrorism-related cases currently before the U.S. Supreme Court that implicate Section 230 of the Communications Decency Act of 1996.

We’ve written before about how the Court might and should rule in Gonzalez (see here and here), but less attention has been devoted to the other Section 230 case on the docket: Twitter v. Taamneh. That’s unfortunate, as a thoughtful reading of the dispute at issue in Taamneh could highlight some of the law’s underlying principles. At first blush, alas, it does not appear that the Court is primed to apply that reading.

During the recent oral arguments, the Court considered whether Twitter (and other social-media companies) can be held liable under the Antiterrorism Act for providing a general communications platform that may be used by terrorists. The question under review by the Court is whether Twitter “‘knowingly’ provided substantial assistance [to terrorist groups] under [the statute] merely because it allegedly could have taken more ‘meaningful’ or ‘aggressive’ action to prevent such use.” Plaintiffs’ (respondents before the Court) theory is, essentially, that Twitter aided and abetted terrorism through its inaction.

The oral argument found the justices grappling with where to draw the line between aiding and abetting, and otherwise legal activity that happens to make it somewhat easier for bad actors to engage in illegal conduct. The nearly three-hour discussion between the justices and the attorneys yielded little in the way of a viable test. But a more concrete focus on the law & economics of collateral liability (which we also describe as “intermediary liability”) would have significantly aided the conversation.   

Taamneh presents a complex question of intermediary liability generally that goes beyond the bounds of a (relatively) simpler Section 230 analysis. As we discussed in our amicus brief in Fleites v. Mindgeek (and as briefly described in this blog post), intermediary liability generally cannot be predicated on the mere existence of harmful or illegal content on an online platform that could, conceivably, have been prevented by some action by the platform or other intermediary.

The specific statute may impose other limits (like the “knowing” requirement in the Antiterrorism Act), but intermediary liability makes sense only when a particular intermediary defendant is positioned to control (and thus remedy) the bad conduct in question, and when imposing liability would cause the intermediary to act in such a way that the benefits of its conduct in deterring harm outweigh the costs of impeding its normal functioning as an intermediary.

Had the Court adopted such an approach in its questioning, it could have better honed in on the proper dividing line between parties whose normal conduct might reasonably give rise to liability (without some heightened effort to mitigate harm) and those whose conduct should not entail this sort of elevated responsibility.

Here, the plaintiffs have framed their case in a way that would essentially collapse this analysis into a strict liability standard by simply asking “did something bad happen on a platform that could have been prevented?” As we discuss below, the plaintiffs’ theory goes too far and would overextend intermediary liability to the point that the social costs would outweigh the benefits of deterrence.

The Law & Economics of Intermediary Liability: Who’s Best Positioned to Monitor and Control?

In our amicus brief in Fleites v. MindGeek (as well as our law review article on Section 230 and intermediary liability), we argued that, in limited circumstances, the law should (and does) place responsibility on intermediaries to monitor and control conduct. It is not always sufficient to aim legal sanctions solely at the parties who commit harms directly—e.g., where harms are committed by many pseudonymous individuals dispersed across large online services. In such cases, social costs may be minimized when legal responsibility is placed upon the least-cost avoider: the party in the best position to limit harm, even if it is not the party directly committing the harm.

Thus, in some circumstances, intermediaries (like Twitter) may be the least-cost avoider, such as when information costs are sufficiently low that effective monitoring and control of end users is possible, and when pseudonymity makes remedies against end users ineffective.

But there are costs to imposing such liability—including, importantly, “collateral censorship” of user-generated content by online social-media platforms. This manifests in platforms acting more defensively—taking down more speech, and generally moving in a direction that would make the Internet less amenable to open, public discussion—in an effort to avoid liability. Indeed, a core reason that Section 230 exists in the first place is to reduce these costs. (Whether Section 230 gets the balance correct is another matter, which we take up at length in our law review article linked above).

From an economic perspective, liability should be imposed on the party or parties best positioned to deter the harms in question, so long as the social costs incurred by, and as a result of, enforcement do not exceed the social gains realized. In other words, there is a delicate balance that must be struck to determine when intermediary liability makes sense in a given case. On the one hand, we want illicit content to be deterred, and on the other, we want to preserve the open nature of the Internet. The costs generated from the over-deterrence of legal, beneficial speech is why intermediary liability for user-generated content can’t be applied on a strict-liability basis, and why some bad content will always exist in the system.

The Spectrum of Properly Construed Intermediary Liability: Lessons from Fleites v. Mindgeek

Fleites v. Mindgeek illustrates well that proper application of liability to intermedium exists on a spectrum. Mindgeek—the owner/operator of the website Pornhub—was sued under Racketeer Influenced and Corrupt Organizations Act (RICO) and Victims of Trafficking and Violence Protection Act (TVPA) theories for promoting and profiting from nonconsensual pornography and human trafficking. But the plaintiffs also joined Visa as a defendant, claiming that Visa knowingly provided payment processing for some of Pornhub’s services, making it an aider/abettor.

The “best” defendants, obviously, would be the individuals actually producing the illicit content, but limiting enforcement to direct actors may be insufficient. The statute therefore contemplates bringing enforcement actions against certain intermediaries for aiding and abetting. But there are a host of intermediaries you could theoretically bring into a liability scheme. First, obviously, is Mindgeek, as the platform operator. Plaintiffs felt that Visa was also sufficiently connected to the harm by processing payments for MindGeek users and content posters, and that it should therefore bear liability, as well.

The problem, however, is that there is no limiting principle in the plaintiffs’ theory of the case against Visa. Theoretically, the group of intermediaries “facilitating” the illicit conduct is practically limitless. As we pointed out in our Fleites amicus:

In theory, any sufficiently large firm with a role in the commerce at issue could be deemed liable if all that is required is that its services “allow[]” the alleged principal actors to continue to do business. FedEx, for example, would be liable for continuing to deliver packages to MindGeek’s address. The local waste management company would be liable for continuing to service the building in which MindGeek’s offices are located. And every online search provider and Internet service provider would be liable for continuing to provide service to anyone searching for or viewing legal content on MindGeek’s sites.

Twitter’s attorney in Taamneh, Seth Waxman, made much the same point in responding to Justice Sonia Sotomayor:

…the rule that the 9th Circuit has posited and that the plaintiffs embrace… means that as a matter of course, every time somebody is injured by an act of international terrorism committed, planned, or supported by a foreign terrorist organization, each one of these platforms will be liable in treble damages and so will the telephone companies that provided telephone service, the bus company or the taxi company that allowed the terrorists to move about freely. [emphasis added]

In our Fleites amicus, we argued that a more practical approach is needed; one that tries to draw a sensible line on this liability spectrum. Most importantly, we argued that Visa was not in a position to monitor and control what happened on MindGeek’s platform, and thus was a poor candidate for extending intermediary liability. In that case, because of the complexities of the payment-processing network, Visa had no visibility into what specific content was being purchased, what content was being uploaded to Pornhub, and which individuals may have been uploading illicit content. Worse, the only evidence—if it can be called that—that Visa was aware that anything illicit was happening consisted of news reports in the mainstream media, which may or may not have been accurate, and on which Visa was unable to do any meaningful follow-up investigation.

Our Fleites brief didn’t explicitly consider MindGeek’s potential liability. But MindGeek obviously is in a much better position to monitor and control illicit content. With that said, merely having the ability to monitor and control is not sufficient. Given that content moderation is necessarily an imperfect activity, there will always be some bad content that slips through. Thus, the relevant question is, under the circumstances, did the intermediary act reasonably—e.g., did it comply with best practices—in attempting to identify, remove, and deter illicit content?

In Visa’s case, the answer is not difficult. Given that it had no way to know about or single out transactions as likely to be illegal, its only recourse to reduce harm (and its liability risk) would be to cut off all payment services for Mindgeek. The constraints on perfectly legal conduct that this would entail certainly far outweigh the benefits of reducing illegal activity.

Moreover, such a theory could require Visa to stop processing payments for an enormous swath of legal activity outside of PornHub. For example, purveyors of illegal content on PornHub use ISP services to post their content. A theory of liability that held Visa responsible simply because it plays some small part in facilitating the illegal activity’s existence would presumably also require Visa to shut off payments to ISPs—certainly, that would also curtail the amount of illegal content.

With MindGeek, the answer is a bit more difficult. The anonymous or pseudonymous posting of pornographic content makes it extremely difficult to go after end users. But knowing that human trafficking and nonconsensual pornography are endemic problems, and knowing (as it arguably did) that such content was regularly posted on Pornhub, Mindgeek could be deemed to have acted unreasonably for not having exercised very strict control over its users (at minimum, say, by verifying users’ real identities to facilitate law enforcement against bad actors and deter the posting of illegal content). Indeed, it is worth noting that MindGeek/Pornhub did implement exactly this control, among others, following the public attention arising from news reports of nonconsensual and trafficking-related content on the site. 

But liability for MindGeek is only even plausible given that it might be able to act in such a way that imposes greater burdens on illegal content providers without deterring excessive amounts of legal content. If its only reasonable means of acting would be, say, to shut down PornHub entirely, then just as with Visa, the cost of imposing liability in terms of this “collateral censorship” would surely outweigh the benefits.

Applying the Law & Economics of Collateral Liability to Twitter in Taamneh

Contrast the situation of MindGeek in Fleites with Twitter in Taamneh. Twitter may seem to be a good candidate for intermediary liability. It also has the ability to monitor and control what is posted on its platform. And it faces a similar problem of pseudonymous posting that may make it difficult to go after end users for terrorist activity. But this is not the end of the analysis.

Given that Twitter operates a platform that hosts the general—and overwhelmingly legal—discussions of hundreds of millions of users, posting billions of pieces of content, it would be reasonable to impose a heightened responsibility on Twitter only if it could exercise it without excessively deterring the copious legal content on its platform.

At the same time, Twitter does have active policies to police and remove terrorist content. The relevant question, then, is not whether it should do anything to police such content, but whether a failure to do some unspecified amount more was unreasonable, such that its conduct should constitute aiding and abetting terrorism.

Under the Antiterrorism Act, because the basis of liability is “knowingly providing substantial assistance” to a person who committed an act of international terrorism, “unreasonableness” here would have to mean that the failure to do more transforms its conduct from insubstantial to substantial assistance and/or that the failure to do more constitutes a sort of willful blindness. 

The problem is that doing more—policing its site better and removing more illegal content—would do nothing to alter the extent of assistance it provides to the illegal content that remains. And by the same token, almost by definition, Twitter does not “know” about illegal content it fails to remove. In theory, there is always “more” it could do. But given the inherent imperfections of content moderation at scale, this will always be true, right up to the point that the platform is effectively forced to shut down its service entirely.  

This doesn’t mean that reasonable content moderation couldn’t entail something more than Twitter was doing. But it does mean that the mere existence of illegal content that, in theory, Twitter could have stopped can’t be the basis of liability. And yet the Taamneh plaintiffs make no allegation that acts of terrorism were actually planned on Twitter’s platform, and offer no reasonable basis on which Twitter could have practical knowledge of such activity or practical opportunity to control it.

Nor did plaintiffs point out any examples where Twitter had actual knowledge of such content or users and failed to remove them. Most importantly, the plaintiffs did not demonstrate that any particular content-moderation activities (short of shutting down Twitter entirely) would have resulted in Twitter’s knowledge of or ability to control terrorist activity. Had they done so, it could conceivably constitute a basis for liability. But if the only practical action Twitter can take to avoid liability and prevent harm entails shutting down massive amounts of legal speech, the failure to do so cannot be deemed unreasonable or provide the basis for liability.   

And, again, such a theory of liability would contain no viable limiting principle if it does not consider the practical ability to control harmful conduct without imposing excessively costly collateral damage. Indeed, what in principle would separate a search engine from Twitter, if the search engine linked to an alleged terrorist’s account? Both entities would have access to news reports, and could thus be assumed to have a generalized knowledge that terrorist content might exist on Twitter. The implication of this case, if the plaintiff’s theory is accepted, is that Google would be forced to delist Twitter whenever a news article appears alleging terrorist activity on the service. Obviously, that is untenable for the same reason it’s not tenable to impose an effective obligation on Twitter to remove all terrorist content: the costs of lost legal speech and activity.   

Justice Ketanji Brown Jackson seemingly had the same thought when she pointedly asked whether the plaintiffs’ theory would mean that Linda Hamilton in the Halberstram v. Welch case could have been held liable for aiding and abetting, merely for taking care of Bernard Welch’s kids at home while Welch went out committing burglaries and the murder of Michael Halberstram (instead of the real reason she was held liable, which was for doing Welch’s bookkeeping and helping sell stolen items). As Jackson put it:

…[I]n the Welch case… her taking care of his children [was] assisting him so that he doesn’t have to be at home at night? He’s actually out committing robberies. She would be assisting his… illegal activities, but I understood that what made her liable in this situation is that the assistance that she was providing was… assistance that was directly aimed at the criminal activity. It was not sort of this indirect supporting him so that he can actually engage in the criminal activity.

In sum, the theory propounded by the plaintiffs (and accepted by the 9th U.S. Circuit Court of Appeals) is just too far afield for holding Twitter liable. As Twitter put it in its reply brief, the plaintiffs’ theory (and the 9th Circuit’s holding) is that:

…providers of generally available, generic services can be held responsible for terrorist attacks anywhere in the world that had no specific connection to their offerings, so long as a plaintiff alleges (a) general awareness that terrorist supporters were among the billions who used the services, (b) such use aided the organization’s broader enterprise, though not the specific attack that injured the plaintiffs, and (c) the defendant’s attempts to preclude that use could have been more effective.

Conclusion

If Section 230 immunity isn’t found to apply in Gonzalez v. Google, and the complaint in Taamneh is allowed to go forward, the most likely response of social-media companies will be to reduce the potential for liability by further restricting access to their platforms. This could mean review by some moderator or algorithm of messages or videos before they are posted to ensure that there is no terrorist content. Or it could mean review of users’ profiles before they are able to join the platform to try to ascertain their political leanings or associations with known terrorist groups. Such restrictions would entail copious false negatives, along with considerable costs to users and to open Internet speech.

And in the end, some amount of terrorist content would still get through. If the plaintiffs’ theory leads to liability in Taamneh, it’s hard to see how the same principle wouldn’t entail liability even under these theoretical, heightened practices. Absent a focus on an intermediary defendant’s ability to control harmful content or conduct, without imposing excessive costs on legal content or conduct, the theory of liability has no viable limit.

In sum, to hold Twitter (or other social-media platforms) liable under the facts presented in Taamneh would stretch intermediary liability far beyond its sensible bounds. While Twitter may seem a good candidate for intermediary liability in theory, it should not be held liable for, in effect, simply providing its services.

Perhaps Section 230’s blanket immunity is excessive. Perhaps there is a proper standard that could impose liability on online intermediaries for user-generated content in limited circumstances properly tied to their ability to control harmful actors and the costs of doing so. But liability in the circumstances suggested by the Taamneh plaintiffs—effectively amounting to strict liability—would be an even bigger mistake in the opposite direction.