NOEL KING, HOST:
There are rumors that have gone viral on Twitter and Facebook that left-wing activists started the fires the wildfires in Oregon. Those rumors are false. But so far, these companies have failed to stop misinformation, some of it dangerous, from spreading. Facebook, I should note, is a financial supporter of NPR. And here's our Shannon Bond.
SHANNON BOND, BYLINE: Cameron Hill and his family were fleeing fires in Clackamas County south of Portland. And they'd heard some disturbing rumors.
CAMERON HILL: I heard that police had several activists in custody...
MONICA SAMAYOA, BYLINE: Really?
HILL: ...Down in Eugene starting - actually seen starting fires.
BOND: That's Hill talking with Oregon Public Broadcasting's Monica Samayoa. These arson claims were not true, but they were lighting up social media. The rumor was the fires had been set by antifascist activists, known as antifa, or Black Lives Matter protesters. The rumors caused so much disruption, local police departments took to Facebook and Twitter to beg people to stop spreading them. They said there was no evidence that any political or activist groups were behind the fires. Tim Fox is a captain with the Oregon State Police.
TIM FOX: You know, all these rumors and things that are going around are tough because we have to find people to respond to them, to investigate them, to check them out.
BOND: Part of the reason these claims spread so widely on Facebook is that the world's biggest social network rewards engagement. Posts that get lots of shares, comments and likes get shown to more people, quickly amplifying their reach. As the fire rumors proliferated, Facebook did put warnings on some posts its fact-checkers found false. And after the FBI put out a statement debunking the rumors, Facebook began removing posts entirely. But by then, the rumors had been circulating for several days.
KAREN KORNBLUH: And what that said to us is that they're waiting too long.
BOND: Karen Kornbluh and her research team at The German Marshall Fund found these rumors spreading in private Facebook groups, some with hundreds of thousands of members. And the claims were being amplified by social media accounts known to spread false information, like followers of QAnon, a baseless conspiracy theory. A Facebook spokesman says the company acts aggressively to stop misinformation. But what happened in Oregon shows that once this kind of hoax starts spreading, it's really hard to stamp out.
DOLORES ALBARRACIN: When you think of the psychology of misinformation, you know, you can think of something like molding clay.
BOND: Dolores Albarracin is a psychology professor at the University of Illinois.
ALBARRACIN: And when you have soft clay, you can print anything you want onto it. Once it dries out, though, that's it. Your print or shape is set.
BOND: So while fact checks and removing posts can help, the real challenge is stopping harmful hoaxes from going viral in the first place. And some experts have a new idea about how to hit pause on social media's powerful amplification engine. Erin Simpson at the left-leaning Center for American Progress says the inspiration is the stock market.
ERIN SIMPSON: So if the S&P drops really suddenly, we've had these thresholds in place for, you know, a lot of years now that the market will stop and that will automatically trigger, like, review.
BOND: Those automatic triggers are called circuit breakers. Simpson says that's what social media - needs a circuit breaker to stop the viral spread that platforms are designed to encourage. So when a controversial topic is gaining steam, Facebook or Twitter could limit its reach while reviewing disputed information.
SIMPSON: A system like this could maybe make it harder for stuff to go viral, instead of the status quo, which is a set of Facebook business products make it easier to go viral.
BOND: The idea is even gaining traction inside Facebook. It says it's testing this kind of speed bump for viral posts. Shannon Bond, NPR News.
(SOUNDBITE OF MARLEY CARROLL'S "MIGRATION") Transcript provided by NPR, Copyright NPR.
