HMRC has published partially completed details of a privacy impact assessment for the use of Voice Biometric Identification (Voice ID) technology. This aims to help reduce fraud and it seems entirely probable that it will be used in future, if HMRC manage more fully automated services.
Voice ID as been used since mid-January 2017 and has been initially only available to Tax Credit and some Self-Assessment customers. The impact assessment (which seems to have been prepared in 2017) gives no timings on its future development but it is apparently being rolled out to other lines of business.
Once enrolled a caller gives a voice sample: they are asked to repeat the phrase 'my voice is my password' up to five times. A voiceprint includes more than 100 unique physical and behavioral characteristics of each individual, such as length of the vocal tract, nasal passage, pitch, accent, etc. According to HMRC, Independent research has shown that a voiceprint is as unique to an individual as a fingerprint.
HMRC says that it will disclose the use of voice identification technology to taxpayers, who will also have the ability to opt-out, should they choose to. Voiceprints are encrypted and stored in a secure database behind the firewall, just like any other sensitive customer data.
The published impact form is incomplete, we presume that the completed version will be available once the assessment consultation is complete.
Source: HMRC Impact Assessment