In the modern media, such as in films and television, the crime genre has taken off with a lot of success. In these types of productions, it is often the case that a team of investigators will use modern techniques and advanced methods to calculate who has committed the crime, such as in the hit multitude of series that make up the CSI brand. Other shows, such as ‘The Mentalist’ revolve around the characters' ability to read people and tell when a criminal is lying, and those such as ‘Sherlock’ revolve around the detective’s ability to deduct what has happened from simply observing details at the crime scene. In reality though, the use of criminology to find offenders is much more strategic, and is, as of yet, far less advanced.
In the real world, criminal profilers are used to try and get some idea of the personality that the offender has, and other details about them, such as where, roughly they live, or their age and gender. There are just a few of these in the country, and it is an extremely hard field to get into, with those that are asked to help, being used more on request, than by actually seeking out jobs themselves. This is because using a criminal profiler is very rare, only happening in particularly serious cases every so often. It would be far too expensive and time-consuming to try and profile the offender that is behind every crime, and this means that very few are needed, with only those at the top end of the field being considered for use. They use details and evidence from the crime scene to make assumptions about the offender, and though these, with a good profiler, can be very accurate, they are not fool-proof, and can lead to false accusations.
There are two main approaches to this style of investigation. The first is the Top-Down Approach. This is used in the United States, by the FBI, and very little is known about the details of how they use this, since they keep all information about it confidential. They believe that by releasing their findings, criminals will be able to work around them. On the other hand, this means that no one can test the basis of their technique, and so it may still be somewhat invalid and unreliable. For this technique, the FBI first interviewed a large sample of offenders that were already in custody, and used the results to come up with categories of offender, that they believe all offenders can be applied to. When searching for a new offender, they then sort them into one of these general groups from what details they do have, and use their prior knowledge of the group to understand what the offender will be like, and what they will do next.
The other approach often used, is the Bottom-up approach. This is used more commonly in the UK, by profilers such as Professor David Canter, who works on cases of serial murder, to try and understand the individual mind behind the crime. This looks in more detail at various specific characteristics of the offender, rather than a generalised category, as the Top-down Approach does, using very minute details found at the scene to make predictions, yet, with more specific predictions, there will also be greater likelihood of them being wrong, and of course, the profiling will be a great deal more time-consuming.
In general, these techniques are very rare, taking place only for those criminals who are particularly difficult to pin down. The use of science to analyse the crime scene, as seen in CSI, is also very rare now, mainly because it is just too expensive, but if techniques and scientific knowledge continue to develop, there is still some potential for streamlining the investigation process. In general though, the ideas these films and television shows portray, remain firmly within the realm of science fiction.
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