Police officers are being given mobile finger print scanners to instantly identify suspected criminals and illegal immigrants.
Two hundred and fifty of the new pocket-sized devices are being trialled in West Yorkshire before being rolled out by the Home Office across the country.
The scanners, which cost less than £300 each, can be used by any officer to take two fingerprints from a suspect.
They are then checked in seconds against records held in two national databases of fingerprints called IABS and IDENT1.
IABS contains the fingerprints of all processed asylum seekers, while IDENT1, designed and managed by American aerospace and defence technology giant Northrop Grunman, holds data from people who have been previously arrested in the UK.
The scanners access records via the Biometric Services Gateway described by the Home Office as "a common platform for future biometrics services".
The announcement that the devices can be used to identify illegal immigrants comes less than a month after MPs on the Home Affairs Select Committee expressed concern over a 10% error rate in official lists of "disqualified people".
According to Home Office documentation, the IABS system holds "information that the person gave to the UK Border Agency" which can be used "to check if the person was removed (or made a voluntary departure), which will show the destination country".
Chief Inspector Ian Williams of West Yorkshire Police acknowledged that the devices will raise some concerns, but said they will only be used where an offence is suspected and the person's identity is in doubt.
More from West Yorkshire
"There are human rights concerns that people will have about us using this technology," he said. "But to reassure people… the fingerprints themselves don't get held on our device, they are used for the purposes of the search and then they're gone."
Minister for Policing and the Fire Service Nick Hurd said: "It's clear that by embracing technology the police can improve efficiency and, if all forces delivered the level of productivity from mobile working as the leading forces, the average officer could spend an hour a day extra on the frontline."