In March, as claims about the dangers and ineffectiveness of coronavirus vaccines spun across social media and undermined attempts to stop the spread of the virus, some Facebook employees thought they had found a way to help.
By subtly altering how posts about vaccines are ranked in people's newsfeeds, researchers at the company realised they could curtail the misleading information individuals saw about COVID-19 vaccines and offer users posts from legitimate sources like the World Health Organisation.
"Given these results, I'm assuming we're hoping to launch ASAP," one Facebook employee wrote in March, responding to the internal memo about the study.
Instead, Facebook shelved some suggestions from the study. Other changes weren't made until April.
When another Facebook researcher suggested disabling comments on vaccine posts in March until the platform could do a better job of tackling anti-vaccine messages lurking in them, that proposal was ignored.
Critics say Facebook was slow to act because it worried it might impact the company's profits.
"Why would you not remove comments? Because engagement is the only thing that matters," said Imran Ahmed, the CEO of the Centre for Countering Digital Hate, an internet watchdog group. "It drives attention and attention equals eyeballs and eyeballs equal ad revenue."
In an emailed statement, Facebook said it has made "considerable progress" this year with downgrading vaccine misinformation in users' feeds.
Facebook's internal discussions were revealed in disclosures made to the Securities and Exchange Commission and provided to Congress in redacted form by former Facebook employee-turned-whistleblower Frances Haugen's legal counsel. The redacted versions received by Congress were obtained by a consortium of news organisations, including The Associated Press.
They shows that in the midst of the COVID-19 pandemic, Facebook carefully investigated how its platforms spread misinformation about life-saving vaccines. They also reveal rank-and-file employees regularly suggested solutions for countering anti-vaccine misinformation on the site, to no avail.
The inaction raises questions about whether Facebook prioritised controversy and division over the health of its users.
"These people are selling fear and outrage," said Roger McNamee, a Silicon Valley venture capitalist and early investor in Facebook who is now a vocal critic. "It is not a fluke. It is a business model."
Typically, Facebook ranks posts by engagement - the total number of likes, dislikes, comments and reshares. That ranking scheme may work well for innocuous subjects like recipes, dog photos or the latest viral singalong. But Facebook's own documents show that when it comes to divisive, contentious issues like vaccines, engagement-based ranking only emphasises polarisation, disagreement and doubt.
To study ways to reduce vaccine misinformation, Facebook researchers changed how posts are ranked for more than 6,000 users in the US, Mexico, Brazil and the Philippines. Instead of seeing posts about vaccines that were chosen based on their engagement, these users saw posts selected for their trustworthiness.
The results were striking: a nearly 12 per cent decrease in content that made claims debunked by fact-checkers and an 8 per cent increase in content from authoritative public health organisations such as the WHO or US Centres for Disease Control.
Employees at the company reacted with exuberance, according to internal exchanges.
"Is there any reason we wouldn't do this?" one Facebook employee wrote in response.
Facebook said it did implement many of the study's findings - but not for another month, a delay that came at a pivotal stage of the global vaccine rollout.
In a statement, company spokeswoman Dani Lever said the internal documents "don't represent the considerable progress we have made since that time in promoting reliable information about COVID-19 and expanding our policies to remove more harmful COVID and vaccine misinformation."
The company also said it took time to consider and implement the changes.
Yet the need to act urgently couldn't have been clearer: At that time, states across the US were rolling out vaccines to their most vulnerable - the elderly and sick. And public health officials were worried. Only 10 per cent of the population had received their first dose of a COVID-19 vaccine.
Company research in February found that as much as 60 per cent of the comments on vaccine posts were anti-vaccine or vaccine reluctant.
Even worse, company employees admitted they didn't have a handle on catching those comments, or a policy in place to take them down.
"Our ability to detect (vaccine hesitancy) in comments is bad in English - and basically non-existent elsewhere," another internal memo posted on March 2 said.
Some Facebook employees suggesting disabling all commenting on vaccine posts while the company worked on a solution.
The suggestion went nowhere.
Instead, Facebook CEO Mark Zuckerberg announced on March 15 that the company would start labelling posts about vaccines that described them as safe.
The move allowed Facebook to continue to get high engagement - and ultimately profit - off anti-vaccine comments, said Ahmed of the Centre for Countering Digital Hate.
"Facebook has taken decisions which have led to people receiving misinformation which caused them to die," Ahmed said. "At this point, there should be a murder investigation."
Australian Associated Press