Brazil Election Disinfo

Amnesty International has warned that Meta may be failing to effectively address election-related disinformation spread through its Facebook Advertisements platform ahead of Brazil's presidential election on 4 October. According to the source, more than half of the ads spreading election-related disinformation were accepted by Facebook.

The experiment conducted by Amnesty International involved submitting 15 Brazilian Portuguese-language ads to Facebook, targeted solely to Brazil's voting age population, to assess how the platform's ad moderation systems treated election-related content. The ads were designed to reflect three tactics that are often used by politicians and candidates to support authoritarian practices: electoral delegitimization, enemy construction, and security-focused authoritarianism.

The Experiment

Amnesty International analyzed online conversations and public sentiment on social media, as well as Portuguese-language content on the Facebook and X platforms between January and May 2026, to help ground the ads in real-world election narratives that were circulating in Brazil. The 14 disinformation ads were designed to violate Meta's policy on misinformation, namely the section focusing on voter or census interference.

The ads were submitted from London, and the Facebook account used to submit the ads had not completed Meta's Confirm Your Identity process. Researchers were not physically located in Brazil and did not use a VPN to create the appearance that the ads were being submitted from Brazil. The ads were scheduled to run at a future date, allowing Amnesty International to test the platforms' ad review processes while ensuring that any ads accepted by the platforms could be cancelled before publication.

Findings

Facebook approved eight ads that contained disinformation, and none of the seven rejected ads were explicitly rejected on the basis of disinformation. The seven rejected ads, including one neutral ad, were declined on the basis that they concerned Ads about social issues, elections or politics. The rejection notices did not indicate that the ads had been rejected because of their content.

The following table summarizes the findings of the experiment:

Amnesty International also identified weaknesses in the safeguards applied when election-related ads were submitted. The ads were allowed to be submitted without declaring that the ads fell within Facebook's Special Ad Categories as required by electoral law in Brazil as well as Meta's own policies regarding election-related ads.

According to Jurema Werneck, Executive Director of Amnesty International Brazil, the fact that Meta's moderation system failed to catch more than half of Amnesty International's election-related disinformation ads is deeply alarming. Ummar Bashir, Researcher and Advisor on Artificial Intelligence and Human Rights, noted that the investigation indicates that Facebook's moderation systems may be failing to reliably detect election-related disinformation content.

The fact that the ads could be submitted from outside Brazil raises concerns that inadequate verification and disclosure controls may create vulnerabilities that could be exploited by domestic or foreign actors seeking to influence electoral processes. This failure to apply legally required electoral disclosures, and the submission of the ads from outside Brazil raise serious concerns about the risk of disinformation campaigns, both by domestic and foreign actors, interfering with electoral processes, as well as broader questions about Meta's moderation systems to identify these risks. Amnesty International wrote to Meta on 21 July 2026, seeking its response to allegations that Facebook's advertising moderation systems failed to detect election-related disinformation, and raising concerns about whether the company has adequate systems to identify, assess and mitigate related human rights risks. Meta has not responded at the time of publication. The ads were cancelled before publication, preventing them from going live and avoiding potential human rights harms or other ethical risks, similar to how teams check the standings to avoid potential risks in their strategies.