Before carrying out mass shooting attacks in Pittsburgh and New Zealand, alleged white supremacist terrorists Robert Bowers and Brenton Tarrant frequented fringe social networking sites that, according to an important new study, serve as echo chambers for the most virulent forms of antisemitism and racism, and active recruiting grounds for potential terrorists.

The new study, the second in a series of reports co-authored by the Network Contagion Research Institute (NCRI) and the Anti-Defamation League’s Center on Extremism, reveals for the first time how fringe social media sites such as Gab, 4 Chan and 8chan act like virtual “round-the-clock white supremacist rallies” where hateful notions of Jews and other minorities are openly espoused and closely associated with violence as a solution.

Researchers analyzed millions of conversations on Gab, the site frequented by Pittsburgh synagogue shooter Bowers, and 8chan, the site favored by Christchurch mosque shooter Brenton Tarrant. The results showed disturbing patterns of increasingly hateful rhetoric after the shootings and also revealed linkages between hateful words and conspiratorial ideas about Jews, showing how these ideas spread and mutate across the platforms.

“The data we’ve gathered is the strongest evidence yet of how white supremacists are taking advantage of fringe online social networks to spread hate and encourage likeminded followers to head down the path to violence,” said Jonathan A. Greenblatt, ADL CEO and National Director. “Bowers and Tarrant were deeply conversant in the conspiratorial language of these echo chambers and used coded racist and anti-Semitic language to spread fear and attempt to recruit others into violent acts.”

The new study, “Gab and 8chan: Terrorist Plots Hiding in Plain Sight,” is being submitted into the record of the House Judiciary Committee hearing on white supremacy and extremist use of social media taking place today on Capitol Hill.

The ADL-NCRI study, which employed various data-mining techniques to identify and decode white supremacist rhetoric, analyzed approximately 36 million comments on Gab from August 2016 to January 2018. Researchers deployed machine learning algorithms and frequency analysis to map how strongly words of hate associate with one another and link together hateful and genocidal notions about Jews, migrants and minorities.

Among the findings:

– The research shows an uptick in hateful rhetoric on fringe web communities in the wake of significant political events or highly publicized extremist violence;

– Bowers and Tarrant regularly shared themes associated with the white supremacist narrative of “white genocide,” which holds that the white race is threatened by non-white immigration, orchestrated largely by Jews;

– On these fringe sites, users frequently rely on coded, ironic language so that only “insiders” can discern their rhetoric’s profoundly hateful intent;

– On Gab, talk of “white genocide” frequently accompanies explicit genocide comments about Jews.

8chan hosts an especially radical iteration of extremism which enabled Tarrant to use it as a site for recruitment and for calling on others to commit violent acts.

“Fringe social media platforms are enabling terrorism in a way that would have been unimaginable even five or ten years ago,” Eileen Hershenov, ADL Senior Vice President of Policy, says in her testimony to the House Judiciary Committee. “The research demonstrates how online propaganda can feed acts of violent terror, and conversely, how violent terror can feed and perpetuate online propaganda. In essence, these platforms serve as round-the-clock white supremacist rallies, amplifying and fulfilling their vitriolic fantasies.”