Social media companies like Facebook don't show you all your friends' posts. You may think they do, but they don't. Instead, an algorithm picks which ones to show you—and which not to show you. How do they decide? The companies won't reveal the details.

Glenn Beck, publisher of the major conservative outlet The Blaze, tells John Stossel that social media companies are biased against conservatives.

Beck says Facebook reduces his posts' reach. And he notes that when a video made fun of Democratic Speaker of the House Nancy Pelosi by slowing down her voice, Facebook put a warning on the post and reduced its reach.

Beck mentions that while social media companies censor right-wing sites that might advocate violence, similar left-wing groups still have Twitter accounts.

In Portland, Oregon, antifa thugs attacked journalist Andy Ngo because he had criticized the group's violent tactics. They kicked him and punched him in the head. The attack left Ngo with brain damage.  

But the account of the local group, Rose City Antifa, is still on Twitter. The group justifies the attack on Ngo on their website: "If you rally the far-right to attack our city and profit by their violence, you are one of them. And the community will stop you, however it can."

Other antifa accounts are still up—despite supporting violence, Beck points out.

"In Austin they were actually calling for the next phase to have people be a paramilitary operation. That was up forever," he tells Stossel. 

The Austin antifa group's Facebook page is still up, linking to a manifesto calling for antifa's opponents to be "beaten bloody…annihilated."

Beck says a double standard exists because social media companies are based in left-wing San Francisco. Also, they mostly hire Democrats.

A Spinquark analysis found dozens of former Democratic staffers working at social media companies.

Stossel pushes back at Beck: "They must hire some Republicans, too."

"They do, but it's about 20 percent and they're not from top-level positions," Beck replies.

In the case of the Pelosi video that was shown to few people, Beck says, "The person who was in charge happened to be…one of the leaders in Nancy Pelosi's office, who had just left Nancy Pelosi's office to go to work [at Facebook]."

But Beck doesn't want hiring quotas. He says he opposes affirmative action for conservatives in social media.

"It bothers me that there are so many conservatives [who] want more regulation," Beck says.