HM REVENUE AND CUSTOMS (HMRC) has been forced to delete biometric voiceprints belonging to 5.1 million taxpayers.
The Information Commissioner (ICO) has told HMRC that its Voice ID service, which it touts as a "high-tech system to improve customer service, did not adhere to data protection rules and that unlawfully-collected records must be deleted by 5 June, the BBC reports.
This follows a complaint lodged by privacy campaign group Big Brother Watch, which found that HMRC's self-assessment helpline "demanded" the creation of a Voice ID by repeating the phrase "my voice is my password".
While an investigation by the group found a workaround by barking "no" at the system three times, the group claims that by "misleading" users of the service, HMRC forcing people to be "railroaded into a mass ID scheme", in breach of data protection laws.
"Far from 'encouraging' customers, HMRC offers no choice but to do as the automated system instructs and create a biometric voice ID for a government database," Big Brother Watch said at the time.
This "shady" scheme didn't go down well with users of the service, either; a Freedom of Information request showed that more than 16,000 Brits opted out of the service.
As per the BBC's report, HMRC changed the way sought permission for voice ID in October and is retaining the biometric information of users who have signed up since.
However, it has begun to delete the voice records of the remaining 5.1 million taxpayers who enrolled in the system before October and who have not called or used the service since.
Director of Big Brother Watch Silkie Carlo, said: "This is a massive success for Big Brother Watch, restoring data rights for millions of ordinary people around the country. To our knowledge, this is the biggest ever deletion of biometric IDs from a state-held database.
"This sets a vital precedent for biometrics collection and the database state, showing that campaigners and the ICO have real teeth and no government department is above the law."
According to the group's blog post, this marks the biggest ever deletion of biometric data from a state-held database in the UK. µ
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