Study Finds Social Media Bots Amplified Political Messages During Brexit Referendum

A network of automated social media accounts significantly influenced public discourse during the 2016 Brexit referendum, according to groundbreaking research by Dr. Marco Bastos. The study revealed that 13,493 Twitter accounts posted content in the crucial four-week period surrounding the vote, only to vanish once polling stations closed.

The investigation identified a sophisticated “Twitterbot” network designed to amplify certain electoral messages and potentially manipulate public opinion. These automated accounts created rapid cascades of tweets that spread through the platform during the campaign period.

Dr. Bastos and his team at City St George’s analyzed user activity metrics and temporal posting patterns to distinguish these bot accounts from genuine human users. Their methodology revealed how the botnet was organized into specialized subnetworks primarily focused on “echoing” content through retweets generated by both algorithms and human operators.

The research demonstrated how these ideologically polarized “echo chambers” on Twitter corresponded to geographically situated social networks. This correlation enabled the researchers to develop an algorithm capable of identifying both user location and political affiliation with significant accuracy.

In subsequent studies, the team discovered that approximately one-third of the messages posted leading up to the referendum were eventually removed from the platform. Only about half of the most active accounts during the referendum period continue to operate publicly, with Twitter having suspended roughly 20 percent of them.

Perhaps most notably, the researchers found that removed content disproportionately favored the Leave campaign. In fact, more pro-Leave messages have disappeared than the entire volume of tweets associated with the Remain campaign.

This research has generated substantial impact across multiple domains. Parliamentary inquiries into social media’s role in spreading disinformation have directly referenced the findings. Dr. Bastos provided oral evidence to the House of Commons Digital, Culture, Media and Sport Select Committee, helping to shape the government’s Online Harms White Paper, which established a “duty of care” for social media providers.

Security organizations have also utilized the research to better understand the threats posed by automated networks to democratic processes. The work was cited in parliamentary debates and referenced in a House of Commons Briefing Paper titled “National Security and Russia.” Dr. Bastos shared insights at a joint expert roundtable discussion hosted by the Royal United Services Institute for Defence Studies and the UK Cabinet Office. His expertise has informed NATO’s Strategic Communications Centre of Excellence and the UK Foreign & Commonwealth Office.

Beyond government and security circles, the research has brought critical issues into public awareness by exposing how social media platforms can be manipulated. The findings received widespread media coverage, raising public consciousness about the vulnerability of democratic processes to digital interference.

As social media continues to evolve as a primary channel for political discourse, this research stands as a crucial reference point for understanding how automated systems can be deployed to influence public opinion during critical democratic events. The findings have contributed significantly to ongoing debates about platform accountability and the need for more robust regulatory frameworks to safeguard electoral integrity in the digital age.