Police have confirmed that forces in England and Wales are passing up to 14 million reads per day from automatic number-plate recognition cameras to a national database.
All but two of England and Wales's police forces are passing data to the National ANPR Data Centre, run by the National Policing Improvement Agency (NPIA) on behalf of the Association of Chief Police Officers (Acpo).
Acpo told GC that the centre is currently taking data from 10,502 ANPR-enabled cameras. Forces use their own equipment, but also take data from converted CCTV cameras run by local authorities. It added that the centre is currently recording between 10 million and 14 million number plates per day, although it has the capacity for 50 million.
The number-plate data, including tightly cropped images of the plates, is held by the centre for two years. Acpo said it has no plans to extend this to five years, a figure cited in earlier police documents about the centre. "Acpo and the NPIA are currently working with the Information Commissioner's Office to ensure that data retention is appropriate and proportionate," said a spokesperson.
The ICO said it is still in discussions over the matter. "The ICO recognises that automatic number-plate recognition can assist in the detection and prevention of crime. However, it is important that where large amounts of personal information are collected and retained, adequate safeguards are in place to protect individuals' privacy," it said.
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"Any prolonged retention would need to be clearly justified based on continuing value, not on the mere chance it may come in useful. We are currently speaking with the relevant organisations involved to ensure any retention period proposed is in compliance with the [Data Protection] Act."
Some police forces also use their ANPR cameras to capture larger images of drivers and passengers for up to one year, although these are not stored on Acpo's central database.
Police forces refuse to disclose the location of their ANPR cameras, although a few systems, such as London's congestion-charging cameras, are known to provide such data to the police. Acpo refused to say how many cameras each force has in use.
The number of police cameras is significantly more than the 6,600 ANPR units run by the Highways Agency and Trafficmaster. These do not transmit full number plates, as they are used to calculate the speed of traffic over sections of road.
