Three mass shooters have now used the the message board website 8Chan to talk about and publish their white supremacist ideology before committing horrific acts.

Congress is now calling for 8chan owner Jim Watkins to testify before the House Homeland Security Committee.

The targets in the three shootings that took place — at a Walmart in El Paso, at a synagogue in Poway, California and a mosque in Christchurch, New Zealand — were religious minorities and immigrants, both of which the shooters defamed in their posts on 8chan.

Tech writer, blogger and podcaster Andy Ihnatko told Boston Public Radio that 8chan was founded "on the absolutist principal that free speech online should be absolute, meaning no moderation of any kind.”

As a result, Ihnatko said, the site “has tended to attract people who were also absolutist free speech people, but also the people who would and have been kicked off of every other message board on the internet.”