All over the country, every day, a car is taken for a joy ride. Parts are stolen and then the car is dumped and sometimes burned out. The police are called to investigate. The detectives have very little information to help them find the criminals – three men were seen leaving the scene in an old white station wagon but nobody remembered the make, model or registration number. Time to use the police database! Searching such a database does some of the same work as a detective, only it is quicker and more efficient.

A police database contains vast amounts of data on criminal records, crime reports, stolen vehicles, fingerprints and other identification checks, and the known operating methods of criminals. The database can be used to cross-check data fed into its system with the data it already contains, and to narrow possibilities to a short list of suspects.

In a case like this, the database may use the data provided by the witnesses to match with another car burglary in another part of the city that involved a similar vehicle. In the case of the other burglary, a witness may have remembered part of the registration number. Using the partial number, the database can be used to make a report of any people recently stopped by police for questioning on other matters who were each driving similar types of cars to that used in the theft. A further search of criminal records may find that some of these people have past offences of a similar nature to that which is being investigated. Further investigation by detectives can then lead to the arrest of the people involved.

A police database could take as long as five minutes to develop a list of suspects; a detective may take days to arrive at the same conclusions. Most probably, without the computer database, such a case would have been left ‘under investigation’ for much longer while other more important crimes took priority.

Police have begun utilising computer technology for 20 years or more particularly databases. Computers are now installed in police cars and police have rapid access to information such as driver records, car ownership, stolen car descriptions, crime reports and a multitude of other data that enables them to complete their job more efficiently.

In most police database systems, a fingerprint identification section has been installed with millions of fingerprints on file. Photographs of criminals are classified by a large number of key features, including scars, shape of face, skin shade and eye contours, as well as standard measures of height, weight etc. The computer is able to match these with data collected at a crime scene. This has helped the police to solve past crimes as well as more recent ones. Manual matching of fingerprints from a crime scene is a very long, inaccurate process. On a computer, matching can be achieved in a few minutes.

In Australia over the past 10 years, car theft rackets have netted many billions of dollars. Most of the cars stolen are transported interstate and resold. Auditors working with large insurance companies have cracked down on the practice by successfully tracing large amounts of money that change hands by using highly effective computer tracking systems. Insurance companies have also used computers to reduce the number of arson payouts. An insurance database can successfully match names and account numbers of people with previous records in crimes such as car theft and arson and this has led to a large increase in arrests.

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