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

• Jurisdiction: United States,Federal
• Law Firm: Jones Day
• Subject Matter: Government, Public Sector, Terrorism, Homeland Security & Defence
• Author: Mr Steven T. Cottreau (Steve), James Gauch, Fahad Habib, Christopher Lovrien, C. Kevin Marshall, Yaakov M. Roth, Emily Goldberg Knox, Gabrielle Pritsker and Justin D. Rattey
• Published date: 30 May 2023

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...