A hidden tracking tool in the website for Reform UK collected private browsing data about potentially millions of people, often without consent, and shared it with Facebook for use in targeted advertising.
An Observer investigation has found that people visiting the website for Nigel Farage’s anti-immigration party had details of their activity captured by a digital surveillance tool known as a Meta pixel.
The tracker – active in the run-up to the election, and as recently as last week – was triggered automatically on loading the Reform site, regardless of whether the person gave consent. It then sent a package of data to Facebook’s parent company, Meta, with details of which webpages had been viewed, when, and the buttons that were clicked.
In some cases, this included sensitive information that could reveal a person’s political beliefs, such as details of those accessing forms to become Reform UK members, linked to a unique Facebook user ID.
Data gathered by the Meta pixel enters the firm’s advertising system and can be used for Meta’s own purposes as well as by advertisers such as Reform to re-target audiences with tailored ads.
It is not known exactly how many people’s data was shared with Meta, but Reform said about 1.1 million visited its website in the month to 15 July. Web archives indicate the tracking tool was in use for at least two years. The party removed it after being contacted for comment last week. The Information Commissioner’s Office (ICO) is examining the case.
The findings raise questions about transparency and digital surveillance following a historic election result for Reform UK, in which it won 14% of the vote and five MPs were elected.
Meta pixel and similar trackers are widely used by political parties and other organisations to collect data for analytics and marketing purposes, but it is against the law to use them unless consent has been “actively and clearly” given.
Data that could reveal a person’s political beliefs is classed as special category and is subject to stricter protections by law because its misuse could pose “significant risks to the individual’s fundamental rights and freedoms”.
Reform UK has claimed that it prioritises privacy and resists “surveillance”, pledging in its manifesto to create a British bill of rights that would protect people’s “freedoms”. It says: “Our data and privacy must be protected. Surveillance of the public must be limited and those monitoring us held to account.”
But the Observer’s testing, checked by independent experts, suggests a failure to follow the rules, with the Meta pixel extracting information before consent had been given, and even if the person clicked “deny”.
Mark Richards, a software engineer and expert in online privacy, said the tracking raised ethical questions.People visiting Reform’s website for research risked being incorrectly labelled as someone with an interest in the party, he said. Meanwhile, those clicking links to become a member were revealing “sensitive political information about who they are and what they believe in”, which they may not wish to share.
Reform UK said it was “committed to protecting the privacy of our website visitors”. It said the tracking tool had been embedded because Reform’s site was made using a template that included it, and that the goal was to “better understand how visitors interact with our website”. The website also uses a third-party tool for managing cookie consent.
A spokesperson for the party said any issues with the Meta pixel appeared to be “cock-up rather than conspiracy”. They added: “We are currently reviewing our procedures to make sure that our use of such tools is transparent and compliant with all relevant regulations.”
In the past, browsing information gathered by tracking tools such as Meta pixel has led to polarising ads being pushed to select groups of voters – and hidden from others – in a practice known as “dark advertising”.
During this year’s election campaign, Reform invested heavily in digital messaging, spending about £100,000 on Facebook ads between May and July. One showed a queue outside a GP surgery, with the words: “Immigration isn’t working”. Another warned of “one migrant every minute” under Labour or the Conservatives.
Some of the ads were targeted at custom audiences, according to Facebook transparency records. However Reform said its targeting was not informed by “anything other than what was told to us in the room and the media pulse”, and data gathered through Meta pixel “was never utilised for political advertising or to influence voting behaviour”.
Meta declined to comment on the specifics. It did not say how data sent to it by Reform UK had been used, or whether it had taken steps to prevent information provided without consent being used for targeting.
A spokesperson for the tech giant, which owns Facebook, Instagram and WhatsApp, said advertisers were responsible for “obtaining the necessary permissions to collect and share data” and that the sending of sensitive information is prohibited.
The ICO said it was examining the information about Reform’s use of tracking pixels as part of a wider review of “the data protection harms arising from use of online tracking technologies”. A spokesperson said: “All too often there’s a lack of accountability for how these tools use people’s personal information, with poor transparency and deceptive design.”