A small group of vocal protesters gathered near the White House on Saturday to demand an investigation into the conspiracy theory known as “Pizzagate.” Several dozen people occupied Lafayette Square to insist that the mainstream media take their claims seriously. They say that Hillary Clinton played a role in a supposed pedophile ring that allegedly operated out of Comet Ping Pong, a local pizza parlor, as evidenced by so-called “codewords” found in leaked emails. This gathering shows the profound power of conspiracy theories, even — or especially — in the face of contrary evidence. In addition to mainstream media coverage, which has roundly debunked Pizzagate, some of the movement’s major supporters have publicly acknowledged that it lacks evidence.

One of the biggest propagators of the theory, right-wing radio host Alex Jones, issued an apology on Saturday for his role in the conspiracy theory, and Edgar Maddison Welch, a North Carolina man, was convicted on Friday of gun charges associated with him taking matters into his own hands and “investigating” Comet Ping Pong in December. So why do people persist in the face of so much evidence? Well, conspiracy theories are most often lobbed by outsiders at people who have power. To many Pizzagate believers, evidence that disproves their theory merely “proves” the depth of the cover-up. For instance, when Welch surrendered to authorities after he found no evidence of the alleged child prostitution, Pizzagate believers pounced on the idea that he was a crisis actor sent to discredit the theory. As of publication of this article, Pizzagate believers are rushing to call Jones a shill for his apology. Some psychologists credit a lack of critical thinking for the staying power of conspiracy theories.

“I don’t have any doubt that Pizzagate is real,” Kori Hayes, a father of three from Middleburg, Florida, told the Chicago Tribune. “But nothing is being said about it.” Hayes attended the protest with his family, all in matching Pizzagate shirts.

This video, posted by prime Pizzagate propagator David Seaman, publicized the protest in early March.