The Home Office identity cards team has reported progress in improving verification by iris scans, but problems with other biometrics apparently persist.
In response to questions from Government Computing News, the Home Office has claimed that the technology for iris scanning has improved. It has not, however, made any claims for fingerprints and facial recognition.
Verification performance of the three main biometrics were recorded as part of the study on user experience published by the Home Office in late 2004. It showed success rates of 96 per cent for iris scans, 81 per cent for fingerprints and 69 per cent for facial recognition.
This has fuelled concerns that the technology for a biometric national identity card, the legislation for which has now received royal assent, does not work well enough for the cards to be used effectively.
Answering a question on whether it regarded the rates as satisfactory, the Home Office replied: "It is true to say that at times in the past some difficulties have been experienced in successfully recording the iris images of people with very dark skin (on some iris systems). The difficulty lay in the ability of the system to successfully locate irises against a darker skin tone.
"The technical solution to this problem is now well understood, and lies in the use of infrared light, correctly controlled exposure and appropriate filters that enable an iris system to successfully locate the iris and record an image irrespective of skin colour."
It did not make any comment on fingerprints or facial recognition.
In response to other questions, the Home Office said it would test the biometric recording and matching systems, and equipment offered by bidders, during the procurement phase. This is due to begin very soon.
It said volunteers would be recruited from different ethnic groups to help it analyse the results to examine any differences in results by demographics. Also, it said that if any shortcomings in the technology arise it would require the suppliers to put in further development work.
This article was originally published at Kablenet.