Identity & Passport Service
Your ref. NBIS DJWO10/09
8 August 2009
Dear Ms Franklin
Correspondence with the
Thank you for your letter dated 20 March 2009 .
That is a long time ago. You may have moved on by now. Nevertheless, herewith my response.
People who understand the probabilistic nature of today's mass consumer biometrics have a different way of speaking to those who don't.
Those who don't, say things like:
Mr Sedgwick makes the point that "each false match needs to be checked by non-biometric means". Professor Daugman, the father of biometrics based on the iris, makes the point that, with the biometrics the Identity & Passport Service (IPS) are using, there would be billions of these checks required . It is therefore not feasible to make them. It is therefore not feasible to say how many duplicate identities there might be on the national Identity Register (NIR) and the quotation you cite is statistically illiterate:
Mr Sedgwick's conclusions depend on a biometric with a false match rate of around 0.00000025% and a false non-match rate of around 1%. There is no such biometric.
Mr Sedgwick acknowledges that and adds that you can't expect a single biometric to have that sort of performance, you need multi-modal biometrics. Asked, in that case, if there is a composite biometric with that sort of performance, he is candid . He doesn't know of any. But there might be one.
In the absence of any such known composite biometric, we cannot check every tenth person on the NIR to see if he or she is a duplicate and we certainly can't check everyone. Politicians are misleading the public if they say we can, perhaps civil servants are misleading politicians when they brief them and perhaps someone else is misleading the civil servants. Goodness knows who that might be. All we know is that it is a false prospectus.
I am, indeed, aware of
that and I am aware that the false non-match rate with the
flat print fingerprinting used by US-VISIT is, or was, something
like 20% .
US-VISIT is a graphic demonstration of why IPS's National
Identity Service (NIS) can't work. You can't tell 20% of
people that they have no right to work in the
And that's why the US Department of Homeland Security, the people who run US-VISIT, recommend against relying on today's mass consumer biometrics for ID cards, as noted at para.81 of the House of Commons Science and Technology Committee report that you cite :
You say that:
The success in detecting fraudulent visa applications is to be applauded. As noted, it is likely that 20% of fraudulent visa applications, ceteris paribus, will have been missed. That point should be made.
It should also be noted
that these biometrics, flat print fingerprints, are not
admissible as evidence in court .
The decisions to grant a
And the public won't be
amused if they find that 20% of them can't work in the
You say that:
Sorry, Haroona, but I am confiscating that "therefore".
The UK Statistics Authority asked for a response from the Chief Scientific Advisor and Director of Research, Development & Statistics at the Home Office, Professor Paul Wiles. For whatever reason, he did not respond, and the short straw was awarded, instead, to you.
IPS are misleading the
Sir David Normington KCB, Permanent Secretary, Home Office
James Hall, Chief Fantasist, Identity & Passport Service
 Quoting from memory, Radio 4 PM programme, 30 June 2009, Eddie Mair in the chair
 http://dematerialisedid.com/PDFs/complete_hi_r.pdf paras.5.14, 33 and 51