Brazilians are about to vote. And they're dealing with familiar viral election lies

As Brazilians head to the polls to pick their next leader, the shadows of the country's 2018 election as well as the 2020 U.S. presidential vote loom large.

Ahead of the first round of voting on Sunday, baseless accusations of electoral fraud are circulating on social media, and President Jair Bolsonaro is laying the groundwork to contest the results — echoing Donald Trump's claims of a stolen election. For many, it raises fears that Brazil is being engulfed by its own internet-fueled "big lie."

Brazil's last presidential contest in 2018 was so plagued by viral falsehoods, journalist Patricia Campos Mello called it "the WhatsApp election."

Campos Mello, a reporter for the newspaper Folha de Sao Paolo, has investigated how Brazilians were flooded with wildly untrue claims on the Meta-owned messaging app hugely popular in Brazil.

Back then, many of the false election narratives focused on hot-button cultural issues, like gender identity and teaching LGBT tolerance in schools, which Bolsonaro derided as handing out a "gay kit" to children. One notorious video that went viral in September 2018 falsely accused Bolsonaro's opponent of distributing baby bottles with penis-shaped nipples at day care centers.

"People actually believed it," Campos Mello said.

Bulk messages spread viral lies

The ability to forward encrypted messages thousands of times to big WhatsApp groups helped hoaxes like that one take off like wildfire. Marketing groups scraped phone numbers and sold campaigns the ability to send hundreds of thousands of WhatApp messages at a time, Campos Mello reported. A study in the weeks leading up to the 2018 vote found half of the most widely shared images in popular political groups on the app were false or misleading.

Bulk WhatsApp messaging "made it faster to reach people and to reach specific groups of voters," Campos Mello said.

Bolsonaro triumphed in 2018. But the experience shook many Brazilians, and over the next few years some things changed.

WhatsApp limited the size of groups and how widely users can forward messages, and it sued some marketing agencies selling bulk messaging services. Brazil's election authorities banned the use of mass messaging for political purposes and vowed to disqualify candidates who spread lies that way.

Today, many Brazilians say they're more skeptical of what they see online.

"I avoid social media as much as possible because of the fraudulent news popping up all the time," said André Benjamin, a civil servant in Rio de Janeiro, speaking in Portuguese.

But even as companies and institutions have raised their guard against electoral falsehoods, the nature of those false claims has also evolved since 2018.

Parallels to Trump

In 2022, "the main theme of disinformation campaigns is our version of 'the big lie,'" Campos Mello said.

The parallels to Trump's false claims that he won the 2020 U.S. election are not subtle.

Bolsonaro has baselessly alleged that Brazil's elections are rigged, that electronic voting machines can't be trusted, and that polls that show him trailing his rival, former President Luiz Inácio Lula da Silva, can't be believed.

Those claims are finding fertile ground online, with posts claiming electronic votes can't be verified and smearing polling agencies gaining traction, said Natália Leal, CEO of fact-checker Lupa.

"There is this lack of credibility and of confidence, and this could be a weapon for Bolsonaro supporters [and the] far right movement," she said.

On social media, Bolsonaro supporters reject polls and point instead to the size of the crowds at the president's rallies — another echo of Trump's rhetoric.

The attacks against polls have even spawned violence.

"There are actual cases of people working for pollsters being harassed [and] beaten," said Chico Marés, Lupa's head of journalism.

And while many social media companies have policies meant to safeguard elections, these messages are spreading across WhatsApp, Facebook, Twitter, TikTok and YouTube, as well as Telegram.

The messaging app has gained popularity as WhatsApp curbed the ability to broadcast bulk messages, and Bolsonaro has urged his supporters to use it.

Brazil's supreme court briefly banned Telegram earlier this year for not removing some posts and accounts spreading falsehoods.

The app is now cooperating with a government program to combat misleading election claims, but researchers say it remains a hotbed of falsehoods.

A recent investigation by the newspaper Estadão found a quarter of messages in Bolsonaro-supporting Telegram groups mentioned election fraud — some directly referring to Trump.

"For this very radicalized part of the population, President Bolsonaro is ahead in the polls, way ahead in the polls, and if he does not win in the first round, that means there was fraud because the electronic voting machines don't work," said Campos Mello.

The question is, if Bolsonaro continues to follow Trump's playbook, are the tech platforms — and Brazil's institutions — prepared for the results?

Editor's note: Facebook and WhatsApp parent Meta pays NPR to license NPR content.

Valdemar Geo contributed to this report.