The 9th US Circuit Court of Appeals ruled 3-0 that the families failed to show that the Nov. 9, 2015 shooting deaths of Lloyd Fields and James Creach at a police training centre in Amman resulted from Twitter's knowing material support of ISIS, which claimed responsibility for the attack.
Circuit Judge Milan Smith said no damages were justified under the federal Anti-Terrorism Act because the plaintiffs, who include the victims' widows, did not show "at least some direct relationship" between their injuries and Twitter's conduct.
He said the plaintiffs did not show any connection between Twitter and the shooter, Jordanian police officer Anwar Abu Zeid, or that the attack was helped by or resulted from ISIS presence on Twitter. The gunman was later killed by local security forces.
"Communication services and equipment are highly interconnected in modern economic and social life, such that the provision of these services and equipment to terrorists could be expected to cause ripples of harm to flow far beyond the defendant's misconduct," Smith wrote. "Nothing in [the law] indicates that Congress intended to provide a remedy to every person reached by these ripples."
Joshua Arisohn, a lawyer for the families, said in an email that his clients were "extremely disappointed" and were weighing their legal options.
"Requiring a more direct connection between the provision of material support to terrorists and the attacks that they carry out contravenes the central purpose of the Anti-Terrorism Act: holding enablers of terrorists accountable," he said.
Wednesday's decision upheld an August 2016 ruling by U.S. District Judge William Orrick in San Francisco.
Alphabet Inc's Google and Facebook Inc have also faced damages lawsuits for allegedly letting entities that US authorities view as terrorist groups use their online platforms.
The case is Fields et al v Twitter Inc, 9th US Circuit Court of Appeals, No. 16-17165.
(This story has not been edited by NDTV staff and is auto-generated from a syndicated feed.)
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