The Firehose on WhatsApp
Days before Brazil's 2018 presidential runoff, the newspaper Folha de S.Paulo revealed a business-funded scheme flooding WhatsApp with disinformation on behalf of the eventual winner. Researchers described the mass-broadcast campaign as a test of the messaging platform's danger to democracy.
On Oct. 28, 2018, the far-right congressman Jair Bolsonaro won Brazil's presidential runoff with 55 percent of the vote, defeating the leftist Fernando Haddad of the Workers' Party. In the days before that vote, the way parts of the campaign had reached voters became a subject of national controversy — not on television or in newspapers, but on WhatsApp.
In a country where messaging apps are for many users a primary gateway to the internet, the private, encrypted platform had become a central channel of the campaign. About 120 million of Brazil's roughly 210 million people used WhatsApp at the time, according to Luca Belli, a professor of internet governance and regulation at the Fundação Getulio Vargas law school in Rio de Janeiro, writing in an analysis republished by PBS NewsHour.
What Folha reported
Days before the runoff, an investigation by Folha de S.Paulo reported that a conservative Brazilian business lobby had bankrolled a multimillion-dollar smear campaign delivered through WhatsApp — activities that, the paper noted, may have constituted an illegal campaign contribution under Brazilian electoral law, which bars companies from funding candidates, according to the same analysis.
The reporting was led by the Folha journalist Patrícia Campos Mello. The Committee to Protect Journalists described her work as exposing “allegations about efforts by a group of businessmen supporting then-presidential candidate Jair Bolsonaro to sponsor bulk messaging on WhatsApp related to the campaign,” in an account on its website. After the stories ran, CPJ said, she was threatened online and by phone.
Doctored images and manipulated audio
The material pushed to voters included doctored photographs portraying senior Workers' Party figures alongside the Cuban revolutionary leader Fidel Castro, audio clips manipulated to misrepresent Haddad's positions and fabricated “fact-checks” that dressed up falsehoods as corrections, according to Belli's account. The design of a closed messaging app, he wrote, made such content hard to trace: messages spread person to person, inside family and community groups, largely out of public view.
The allegations quickly reached the courts. On Oct. 19, 2018, Bolsonaro's campaign was accused of fraud and of spreading fake news, France 24 reported, after the Workers' Party asked Brazil's electoral authorities to investigate the scheme described by Folha.
A warning beyond Brazil
Researchers cast the episode as more than a national scandal. Belli argued that Brazil had become a case study in how disinformation can be industrialized on private messaging platforms, and that its experience should serve as a warning to democracies in the developing world, where cheap data plans and app-centric internet access can concentrate political information inside a single platform.
WhatsApp, owned by Facebook's parent company, said afterward that it had acted against the abuse, banning hundreds of thousands of accounts and later limiting how many times a message could be forwarded. Analysts who study the case say the underlying vulnerability — a closed network where viral falsehoods travel fast and moderation lags — remains a recurring feature of elections well beyond Brazil.