Automatic number plate recognition

Why Thames Valley Police uses ANPR

Automatic Number Plate Recognition (ANPR) technology is used to help detect, deter and disrupt criminality at a local, force, regional and national level, including tackling travelling criminals, organised crime groups and terrorists. ANPR provides extra lines of enquiry and evidence in any investigation of crime and is used by forces throughout England, Wales, Scotland and Northern Ireland.

How it works

As a vehicle passes a police monitored ANPR camera, its registration number is read and instantly checked against database records of vehicles of interest. Police officers can intercept and stop a vehicle, check it for evidence and, where necessary, make arrests. The use of ANPR in this way has proved to be important in the detection of many offences, including locating stolen vehicles, tackling uninsured vehicle use and uncovering cases of major crime. It also allows officers' attention to be drawn to offending vehicles while allowing law abiding drivers to go about their business unhindered.

Access to stored data

ANPR data collected by Thames Valley Police is submitted to the National ANPR Data Centre (NADC) where it is stored together with similar data from other forces for a period of two years.

We have clear rules to control access to ANPR data to ensure that access is for legitimate investigation purposes. Staff can only access ANPR data if it is relevant to their role, and the majority of those who have permission may only do so for a maximum period of 90 days from the date it was collected. Some staff are authorised to access data for up to two years subject to authorisation of a senior officer. After 90 days, access may only be for serious, major or counter terrorism investigations and after 12 months only for major investigations and counter terrorism purposes.

Searches of ANPR data can confirm whether vehicles associated with a known criminal has been in the area at the time of a crime and can dramatically speed up investigations.

Camera locations

In addition to being mounted within police vehicles, police monitored ANPR cameras within Thames Valley are used at fixed locations where they will help to detect, deter and disrupt criminality. In line with national policy, we do not disclose details of our fixed locations as this information is likely to be of benefit to offenders and if known could reduce the value of ANPR to policing.

National guidelines state that, if Thames Valley Police proposes to install additional ANPR cameras, an assessment must be conducted that demonstrates a clear need, taking account of the following factors:

  • National security and counter terrorism;
  • Serious, organised and major crime;
  • local crime;
  • Community confidence and reassurance, and crime prevention and reduction.

In assessing whether new cameras are to be deployed, a Privacy Impact Assessment will be undertaken. We will consult with persons and organisations with a reasonable interest in the proposal unless that would be contrary to the purpose of the development, namely to detect, deter and disrupt criminality.

Thames Valley Police is also committed to regularly review the location of ANPR cameras, in the context of the above criteria, to make sure that the continued deployment remains justified. All reviews will include consideration of the impacts on privacy.

Further information

The Chief Constable is the data controller for the ANPR system operated within Thames Valley Police.

Any requests for information or complaints in relation to ANPR should be made through your local police office, by calling 101 ext 7013171 or email the ANPR Manager direct at John.knight@thamesvalley.pnn.police.uk

(For FOI requests, see site for details or contact publicaccess@thamesvalley.pnn.police.uk)

Further information

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