Twitter, Inc. v. Taamneh

The case arose from a 2017 ISIS attack on an Istanbul nightclub that killed Nawar Alassaf. Her family sued Twitter, Facebook, and Google, alleging that the platforms aided and abetted international terrorism by allowing ISIS to use their services for recruitment and propaganda, thereby failing to adequately detect and remove terrorist content. The U.S. Supreme Court was asked to determine whether the tech companies could be held liable under the Anti-Terrorism Act's aiding-and-abetting provision. The Court unanimously ruled that the plaintiffs' allegations fell short of showing that the platforms gave knowing and substantial assistance to the specific attack, distinguishing general passive inaction from the direct culpable participation required for liability.

The Supreme Court unanimously reversed the Ninth Circuit's judgment, holding that the complaint failed to state a claim for aiding and abetting under 18 U.S.C. § 2333(d). The Court found that the platforms' generalized awareness of ISIS activity and failure to remove content did not constitute knowing and substantial assistance for the specific Reina nightclub attack.

Whether social media companies can be held liable under the Anti-Terrorism Act for aiding and abetting a terrorist attack based solely on the provision of general platform services that were used by the perpetrators.

The ruling significantly narrows the liability exposure of internet platforms under federal anti-terrorism law. It establishes that passive provision of widely available services, even when misused by terrorists, is insufficient to establish secondary liability without direct connection to a specific wrongful act. The decision is viewed as protecting online platforms from overly broad litigation while underscoring that active participation or targeted assistance remains actionable.