© Reuters/Dado Ruvic3D plastic representations of the Twitter, Facebook and Youtube logos are seen in front of a displayed ISIS flag in this photo illustration shot February 3, 2016.
The three daughters of Jared Tucker, who was among the 13 people killed in the August 17 attack, are plaintiffs in the lawsuit. They are represented by their mother and legal guardian Danelle Sinclair. Tucker, 42, of Walnut Creek, was in Europe with his wife, Heidi Nunes-Tucker, celebrating their first wedding anniversary.
The assault was the worst terrorist attack to hit Spain in more than a decade when a vehicle plowed into pedestrians on Barcelona's most popular boulevard, Las Ramblas. Thirteen people died and 130 were wounded.
The three tech companies, the complaint argues, have "for years knowingly and recklessly provided the terrorist group ISIS with accounts to use its social networks as a tool for spreading extremist propaganda, raising funds and attracting new recruits."
© ReutersA Muslim woman holds a sign that reads "ISIS is not Islam" as she takes part in a gathering of different religious groups in rejection of the attack in Barcelona.
The lawsuit hinges on the interpretation of a portion of the 2016 Justice Against Sponsors of Terrorism Act, which provides litigants with broad ways to "seek relief against persons, entities and foreign countries, wherever acting and whenever they may be found, that have provided material support, directly or indirectly, to foreign organizations or persons that engage in terrorist activities against the United States."
Facebook announced recently that it will use artificial intelligence to spot images, videos and text related to terrorism. YouTube, owned by Google, has also said it will be removing terrorist-related content much faster.
Twitter claimed in 2016 that it shut down more than 360,000 accounts linked to terrorist groups.
"We want to be very open with our community about what we're trying to do to make sure that Facebook is a really hostile environment for terror groups," Monika Bickert, director of global policy management at Facebook, told the BBC.
The growing number of ISIS attacks has led big tech firms to focus on removing content uploaded by suspected militants, although many lawmakers and family members of victims have demanded further action.
After a terror attack in London in June, British Prime Minister Theresa May said that more needs to be done to stop ISIS from spreading its propaganda.
"We cannot allow this ideology the safe space it needs to breed. Yet that is precisely what the Internet and the big companies that provide Internet-based services [do]," May said, according to the Independent.
Comment: The drive for censorship is on. Clocking truly dangerous content is understandable, but the net has being widened to included all material dissenting against the Empire.