In mid-October 2017, an article on the site “Book of Truth” (Livro da Verdade in Portuguese) spread like wildfire on Brazil’s most popular social media services.

Vaguely resembling a piece of tabloid copy, the story claimed popular Brazilian drag queen Pabllo Vittar was getting public funding to host a kids TV show on Globo, the Brazilian TV network. Tapping into Brazilian culture wars over gender and politics, the report stirred outrage, claiming that Globo stood to lose 50 million viewers because of Vittar’s hire.

Problem is, none of the claims were true, and the story was soon debunked. Its veracity didn’t seem to matter, however, and as of this writing it’s been shared over 110,000 times on Facebook alone, says fake news researcher Pablo Ortellado, a public policy professor at the University of São Paulo.

But Ortellado believes the fake Vittar story spread even further on Brazil’s dominant messaging platform, also owned by Facebook: WhatsApp.

And because WhatsApp is a private, closed messaging service, fake news researchers don’t have much hard data to go on. Ortellado says they’re primarily able to get information by lurking in large WhatsApp political groups or examining context clues, giving analysts “certainly a tiny fraction of what's going on."

“This was a fake story that did extremely well on Facebook, but on the website there wasn't a share button for Facebook, just WhatsApp,” Ortellado said.

The creation and spread of fake news has alarmed governments the world over, but few countries have expressed as much concern as Brazil. And with good reason, as multiple reports have concluded that fake news stories regularly outperformed real stories in Brazil in 2016. The problem has grown so rampant that Brazil’s national police recently announced plans to find and “punish the authors of ‘fake news’” ahead of this year’s high-stakes presidential elections.

“We have this new phenomenon of fake news sites specifically targeting WhatsApp.”

But WhatsApp adds another complication to Brazil’s fake news quandary: secrecy. Unlike the fully public Twitter, or Facebook, where posts are somewhat public and can more easily be tracked and analyzed by independent parties, WhatsApp is a closed, peer-to-peer messaging service. On WhatsApp, the most toxic aspects of fake news multiply: The platform exacerbates pockets of powerful echo chambers in a political environment already deeply polarized and makes tracking the reach and origins of disinformation particularly difficult for researchers, journalists, and, in Brazil’s case, the federal police.

“We have this new phenomenon of fake news sites specifically targeting WhatsApp — this is probably going to be a problem in the 2018 [national] elections,” Ortellado said.

Total dominance

WhatsApp is nearly ubiquitous in Brazil: 120 million of the country’s roughly 200 million people use the messaging app, making it more popular there than any other app, including Facebook. Further, some 35 percent of its users regularly rely on the messaging platform for their news consumption, according to a WhatsApp-commissioned study.

The volatile political climate in Brazil isn’t helping things, either. Brazilian society is mired in pervasive political corruption, rising racial tension, and extreme polarization. Additionally, Brazilian news media has contracted sharply over the past few years, as more people get their news straight from social media services and put less faith in traditional media. Similar dynamics in the United States led to the spread of fake news on social media during the 2016 election, according to a January 2017 paper published by Stanford University researchers.

“You can have huge networks of people that are totally out of control and are unseen.”

“The conditions that exist in Brazil are just ripe for people’s selective exposure, their confirmation bias, their tribalism,” misinformation researcher Claire Wardle told Bloomberg. And private, peer-to-peer messaging apps like WhatsApp are exacerbating that tribalism, said Rosental Alves, a professor of journalism at the University of Texas-Austin.

“Families and every group you can imagine creates their own private social media network on WhatsApp, and those bubbles are totally out of the control of anybody else,” said Alves. “You can have huge networks of people that are totally out of control and are unseen.”

A representative for WhatsApp declined to comment on fake news in Brazil and noted that while none of the company’s roughly 250 full-time employees are based in Brazil, the company frequently meets with the Brazilian government.

But Alves says these networks on WhatsApp are “fertile for planting false information” that can spread quickly from group to group until it is “out of control.”

A heavy-handed response

The veil of secrecy enjoyed by fake news creators on WhatsApp has elicited a robust response from Brazil’s national police, with its new fake news task force experts and analysts worrying the app could quickly become a vehicle for greater censorship and suppression of free speech. Such fears were fanned last week, when a top police official threatened to invoke a dictatorship-era law in order to move forward with its task force, even if it has no such authority from the Brazilian legislature.

This isn’t the first time WhatsApp has been the source of major political tension in Brazil. The platform has been shut down by Brazilian judges three separate times, most recently in July 2016 in a dispute over sharing data with the police. In March 2016, a Facebook executive did a brief stint in jail for similar reasons. The platform's commitment to user privacy has been lauded by journalists and rights groups.

But with fears mounting about the government’s heavy-handed response and a charged election season led by a former president facing jail time and a right-wing firebrand congressman hoping to become Brazil’s Donald Trump, the messaging app may soon be confronted with one of its biggest obstacles yet, warned a poli sci professor at Rio de Janeiro State University: Brazil’s military.