British government trials of a national ID card system have run into a roadblock, as people who have brown eyes are being misidentified.
"There are difficulties with the technology, not least ... with people with brown eyes rather than other colored eyes," McNulty said.
There have also been reports the system made wrong matches for black, elderly and disabled people, as well as balding men and laborers with worn-down fingerprints.
However, a Home Office spokesman said the database system has an old-fashioned back-up system.
"The database also holds photographs and personal information so an incorrect biometric match would be easily discovered," he said.