This chapter heading seems slightly pretentious, as my limited knowledge will only allow a brief, non-technical description of the most common technology used by the police today.

The Police National Computer – PNC

This began life in the early 1970s as a computerized record of stolen vehicles but it now incorporates a number of useful databases, and is accessible at any time.

Criminal Names

This has details of all convicted, cautioned or recently arrested persons (nominal). It lists convictions, gives a description of the subject, including identifiers such as scars and tattoos, and shows previous addresses and any previous co-defendants.  The file can be searched using the Querying Using Extended Search Techniques (QUEST – I don’t make these names up, I only report them) using elements of the record such as height, age, etc.  A nominal can also be marked as ‘wanted’ if they are sought in connection with the crime, or they can be marked as ‘of interest’.  Both will show the officer who wants the subject arrested or is interested in him or her and the officer’s station and force.  It has links to the Automatic Fingerprint Recognition (AFR) system and the DNA database and is now accessible to the Schengen database (see Chapter 6).


This file has details of registered owners, the vehicle’s tax status, and its chassis and engine numbers. It is updated every day from the Driver and Vehicle Licensing Agency (DVLA).  It has a police element which shows if the car is stolen or is of police interest and what the officer interested wants done – whether they just want to know when and where it has been seen, or whether they want it stopped to identify who the occupants are.  A search can be carried out on a partial description using the Vehicle Online Description Search (VODS) – a boon in major inquiries, where partial registration numbers and descriptions are common.  It is linked with the Motor Insurers’ Bureau database which gives the details of the policyholder, and with the DVLA MOT database.


This fil gives details of all licence holders, their endorsements and whether or not they are disqualified. It is also updated daily from the DVLA database.


This file holds a limited amount of information on property, usually that which can be identified through a serial or registration number, such as engine plant, trailers or firearms.

Local Intelligence Systems

Too many people both in and outside the service use the term ‘intelligence’ without giving any thought to what it means or how it can be differentiated from other similar words such as information, facts, knowledge etc. I have developed a model which I have found useful:

  • data – single elements of fact /rumour concerning criminals or criminal behaviour
  • information – enough data to make an analysis possible, producing some hypothesis concerning criminal or their behaviour
  • intelligence – a hypothesis which is firm enough to act on

For example, X owns a car, registration number ABC 123 (data). He has been seen driving to the south of London contacting a known drugs dealer.  Rumour has it that he is developing his own dealership locally (information).  The hypothesis is that he goes to London to stock up twice a week, so the next time police can wait at his address and stop and search the car on his return from London (intelligence).

All forces have had to develop their own stand-alone systems to record and analyse this data, since the government had been willing to fund the development of a central facility. Computer support is needed to produce a trickle of intelligence; secondly, a computer system can be made available at all times to officers in the field to both record and retrieve information in a way that a card- or paper-based system cannot; thirdly, one force’s system can be made available to another through a secure landline.  The National Police Improvement Agency is currently developing a programme called Impact which aims to link all the existing systems.  It was due to be completed by 2010 but is already behind schedule.  From the difficulties that arose in the investigation into the Yorkshire Ripper case and the failings of intelligence in the bombings of the London Underground one would think that the weaknesses in this approach would be only too obvious to the Home Office, but they have already been short-sighted when it comes to leadership in this area and it is probable that the situation ill be allowed to drift on until the next disaster.

Custody Systems

The whole custody and prosecution process is now computerized. This had led to less paperwork for officers and easier management of the information contained in it.  A major operational gain has been that these systems incorporate a digital camera, so that when prisoners are photographed a digital image is captured.  This means that the photograph database can be searched automatically on description, making it easier to limit the number of photographs shown to witnesses and making the probability of a successful identification more likely.

Automatic Number Plate Recognition Systems

These were used for the first time on any scale by the City of London Police to help them manage the ‘ring of steel’ erected around the city during the Provisional IRA’s sustained attacks in 1992 and 1993. The system allows the car registration number to be checked in real time against the PNC so that its status can be verified.  Successors of the system are now used by most forces.  The tremendous improvement in digital image quality and the reduction in the cost and size of computers means that they can be used proactively to track offenders and gather vehicle-related intelligence.  This is important as most major acquisitive crime, such as drugs trafficking and burglary, requires the use of vehicles, so an ability to carry out remote surveillance without having to use people is invaluable.  It has also meant that traffic cameras can process prosecutions almost completely automatically; when it was first introduced the courts complained about the additional unmanageable workload and the number of prosecutions had to be artificially limited.


Britain is reputedly the most watched country in the world in terms of CCTV coverage. All town centres, shopping malls, major railway stations and bus terminals are routinely covered by them.  The information they provided in the failed attack on the London Underground on 21 July 2005 vividly shows their value to the police.  The first systems were analogue and the images they produced were poor.  This problem was compounded by bad management.  Tapes were used to often so that already poor images became useless, and sometimes they were reused immediately rather than being kept for a set period, in case they contained information whose importance was only realized later.  Most systems are now digital, which has significantly improved the quality of the image and made it cheap and easy to store the recordings for a reasonable period of time (a month).

The major current drawback is the number of officer hours that viewing them takes when trying to find information about an incident. For example, if two men are seen walking away from the location of a car bomb wearing hats and hoods so that the camera cannot see their faces, it is necessary to keep expanding the sweep of the systems viewed in the hope that they will have been picked up by a camera when they are far enough away from the scene to relax their vigilance, perhaps allowing a view of their faces or some other identifying factor such as getting into a car or using a cash machine.

Facial Recognition Systems

These are less common and are still in the process of development. The theory is that if you already have a digital image of the target all you need to do is attach the facial recognition software to a digital camera or digital recording and it will make the match, or at least reduce the number of images that need to be physically searched to a realistic number.  If the software could do it accurately then the match could be made in real time – an enormous operational gain.  The police now have a vast bank of digital images of people arrested and if they are sufficiently interested in someone who is not on that database it is a simple task to go and get one through surveillance.

So what’s the problem? It’s all a matter of geometry.  Nearly all cameras are mounted quite high so as to maximize their range and minimize their intrusiveness.  This means the key distances and angles in the image captured, such as between the eyes, between the nose and the upper lip, or the length of the nose and face, will all be different from those in an image where the shot has been taken at the same level as the subject.  It is possible to compensate for this to some extent but there is no standard height or angle of image capture so that the current systems are limited to those where it is possible to mount the camera to capture the subject ‘face-on’.  A further complicating factor is that photographic features can be affected by changes in light and the background against which the photograph is taken.

Mobile Phones

This is not really technology used by the forces so much as technology used by the public which provides enormous operational and investigative assistance to the police. Mobile phones work through a series of cells and a record is kept of which cell or cells any particular phone is using during a call.  This allows the phone to be tracked, in real time if there is an operational need, and the times and recipient of the calls are also recorded.  A significant number of people have been convicted for causing death by dangerous driving because it has been possible to show that they were using their mobile phone at the time of the collision.

Mobiles give two other benefits. First, they are really just radios, so it is possible to pick them up on a scanner and monitor what is being said without a warrant, as is needed to monitor a landline.  Secondly, although professional and even low-level criminals are aware of the danger of using mobiles which they minimize by using re-carded stolen phones and pay-as-you-go contracts for short periods before either re-carding them again or dumping them, they still tend to keep all their numbers stored on the current card or keep them on a personal phone – the convenience outweighs the danger.  This is a goldmine of information if the police can get their hands on it.


Police make extensive use of technology for tracking and surveillance – the GPS systems used in cars show how small these devices can be and how they can enable the police to track the target vehicle or person accurately and easily. Similarly micro CCTV cameras make bugging relatively straightforward and formidably easy to install and conceal.  If you intend to use these in any detail in your plot I would advise you to consult sites on the Internet.


The major gain from the use of helicopters in terms of technology is their thermal imaging capability. This has revolutionized the service’s ability to work after dark and has resulted in the capture of innumerable criminals, especially burglars and car thieves, who would almost certainly have otherwise made good their escape.


What about the satellite surveillance that is commonly seen in fiction such as the TV series 24 and films like Enemy of the State? Anyone who thinks that this capability is available to the police only has to consider the case of the Washington (or Beltway) sniper.  For a period of three weeks the sniper shot at random targets, usually while they were carrying out some mundane task like filling their cars with petrol or mowing the lawn, killing sixteen people and injuring two.  If there is any city in the world which is likely to have a guardian satellite it is Washington yet the police worked initially on the wrong vehicle, a white van, and called in an aerial reconnaissance aircraft.  In the end the snipers were caught because a member of the public became suspicious on finding them sleeping in a blue Chevrolet saloon similar to the one later circulated by police.


Queen Victoria.


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