These Popular Social Media Sites Are Getting Sued Over Alleged Support for ISIS

June 16, 2016, 3:32 PM UTC
Facebook Said to Plan IPO Filing for as Early as Coming Week
Photograph by Bloomberg via Getty Images

Are sites like Facebook responsible when terrorists use them for recruiting and propaganda? Relatives of victims murdered by ISIS claim they are even though U.S. law makes their legal claims a stretch.

The latest example is a lawsuit filed in California this week against Twitter (TWTR), Facebook, and Google (GOOG) by the family of Nohemi Gonzalez, who was the only American killed in the Paris attacks committed by ISIS last November.

The family blames the sites for providing “material support” to the terrorists, claiming they “use their social networks as a tool for spreading extremist propaganda, raising funds, and attracting new recruits.”

The Gonzalez lawsuit, filed in federal court in California, echoes a similar one filed against Twitter early this year by the widow of a U.S. contractor killed by ISIS in Iraq.

That Twitter case, however, looks set to fail. On Wednesday, U.S. District Judge William Orrick reportedly told a courtroom that any ties between Twitter and the murder were “awfully attenuated,” and that he was inclined to dismiss the case.

Get Data Sheet, Fortune’s technology newsletter.

The issue for the families is both cases is a law called Section 230 of the Communications Decency Act, which shields websites for misdeeds by their users. Many legal scholars consider the law essential to the online economy.

Section 230 is typically used for situations like libel not terrorism, and a lawyer in the Twitter case says he can overcome it by relying on language in the Anti-Terrorism Act.

That law makes it possible for victims to bring civil lawsuits against those who provide “material support” to terrorists.

While neither lawsuits is likely to succeed, they do highlight an uncomfortable situation for popular social media sites: The sites are coming to figure prominently in terrorist activities—much as they are in every other aspect of our lives. In a horrific recent example, a terrorist in France this week broadcast the aftermath of his murders to Facebook Live.

In response to the judge’s comments in the Twitter case, a spokesperson for the company provided a statement.

“While we believe the lawsuit is without merit, we are deeply saddened to hear of this family’s terrible loss,” the statement read in part. “We have teams around the world actively investigating reports of rule violations, identifying violating conduct, partnering with organizations countering extremist content online, and working with law enforcement entities when appropriate.”