U.S. Supreme Court Narrows Scope of Liability Under Anti-Terrorism Act

The U.S. Supreme Court unanimously decided Twitter v. Taamneh, clarifying the meaning of key provisions in the Anti-Terrorism Act ("ATA") and the pleading standard for aiding-and-abetting claims under that law.

On May 18, 2023, the Supreme Court issued its decision in the high-profile Twitter v. Taamneh. Twitter and other social media companies were accused of enabling the Islamic State of Iraq and Syria ("ISIS") to fundraise, recruit members, and distribute propaganda. The plaintiffs include the family members of a victim of the 2017 attack at an Istanbul nightclub, allegedly perpetrated by ISIS. Under the ATA and the 2016 Justice Against Sponsors of Terrorism Act ("JASTA"), such plaintiffs can bring claims against persons and entities that aid and abet acts of international terrorism "by knowingly providing substantial assistance." 18 U.S.C. § 2333(d)(2). The U.S. Court of Appeals for the Ninth Circuit allowed the plaintiffs' claims against Twitter stemming from the attack on the Istanbul nightclub to move forward. 

In its opinion, the Supreme Court unanimously reversed the Ninth Circuit, siding with Twitter and the other social media defendants, and holding that: (i) aiding-and-abetting liability under the ATA requires "a conscious, voluntary, and culpable participation in another's wrongdoing"; and (ii) a defendant must "have aided and abetted the act of international terrorism that injured the plaintiffs." Slip Op. at 17, 21.

First, the Court explained that the framework from, and factors articulated by, the U.S. Court of Appeals for the District of Columbia Circuit in Halberstam v. Welch "reflected and distilled" various common-law principles for aiding and abetting. Id. at 16. And though Congress endorsed the Halberstam framework as the basis for aiding-and-abetting liability under JASTA, as explained in Taamneh, Congress's approval of that framework does not require courts to "hew tightly to the precise formulations that Halberstam used." Id. Rather, "both JASTA and Halberstam's elements and factors rest on the same conceptual core that has animated aiding-and-abetting liability for centuries: that the defendant consciously and culpably 'participate[d]' in a wrongful act so as to help 'make it succeed.'" Id. at 17 (quoting Nye & Nissen v. United States, 336 U.S. 613, 619 (1949)). Thus, aiding-and-abetting under JASTA "refers to a conscious, voluntary, and culpable participation in another's wrongdoing." Id. at 17. 

Second, the Court explained that "aiding and abetting is inherently a rule of secondary liability for specific wrongful acts," rejecting plaintiffs' argument that a defendant need only aid a terrorist organization generally rather than the attack itself. Id. at 18 (emphasis added). It is thus not enough to allege that a defendant substantially assisted "a transcendent 'enterprise' separate from and floating above all the actionable wrongs that constitute it." Id. at 19. "Rather, a defendant must have aided and abetted (by knowingly providing substantial assistance) another person in the commission of the actionable wrong—here, an act of international terrorism," even though, depending on the defendant's state of mind and extent of conduct, that might "not always demand a strict nexus between the alleged assistance and the terrorist act." Id. at 19, 21. 

Applied to the case against Twitter, the Court found that the plaintiffs' claims fell short. Id. Among other things, the Court reasoned that: (i) the plaintiffs "never allege[d]" that ISIS used the social media platforms "to plan or coordinate the [Istanbul] attack,"; (ii) the relationship between the defendants and the Istanbul attack was "highly attenuated"; and (iii) the plaintiffs had failed to point to any "act of encouraging, soliciting, or advising the commission of the [Istanbul] attack" by the defendants. Id. at 22-24. Analogizing to cell phones, email, and the internet generally, the Court explained that merely "providing . . . services to the public writ large" does not render a company culpable for the bad acts of those who use those services. Id. at 23. 

The Court left open the possibility that there may be "situations where the provider of routine services does so in an unusual way or provides such dangerous wares that selling those goods to a terrorist group could constitute aiding and abetting a foreseeable terror attack." Id. at 26. The Court noted that such aid would be "more direct, active, and substantial" than the aid in the case before it. Id

In light of its holding in this case, the Court found it unnecessary to address section 230 of the Communications Decency Act ("CDA") in Gonzalez v. Google LLC, -- S. Ct. --, No. 21-1333 (May 18, 2023). 

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