Critically evalutate the evidence that criminal profiling is effective

It is usually carried out in a three stage process: First, police officers collect crime scene data and forward it to a profiler. second, the profiler conducts an analysis of the crime scene data. and third, the profiler provides predictions about the type of individual likely to have committed the crime in question. (Snook et al,, 2007, 438) There was initial enthusiasm for this approach, especially in the United States where the FBI set up a special ‘Behavioral Science Unit’ which analysed crimes and made recommendations for the application of criminal profiling in serious crime cases. From the beginning it was clear that the process involves multiple skills and multiple agencies, being a technique that combines elements of both art and science (Cook and Hinman, 1999, 230) and crosses over traditionally constructed professional boundaries. There has been discussion about some of the tensions arising from this multi-disciplinarity, and the gulf between researchers and practitioners. (Alison et al, 2004). Critical opinion on the practice of criminal profiling has been mixed, ranging from positive evaluations to serious doubts as to whether criminal profiling is any more valuable than common sense. This paper reviews the underpinning theories behind criminal profiling, discusses its methodologies and the problems that can arise in its use, and then finally evaluates its effectiveness. Theories behind criminal profiling. Psychology is the major science behind criminal profiling and its origins can be traced back to the beginning of the twentieth century: the inferring of general characteristics of a person on the basis of a limited amount of information about them, has scientific roots in psychometric testing. (Canter, 2000, p. 3) This in turn is based on a large body of research into the variation that exists between individuals. Psychologists searched for ways of isolating small individual features which, when considered together and against a large database can predict with some degree of accuracy what type of personality a person has and how they are likely to behave in different situations. The predictions are inferred, which means they start with what is known, but move into speculation based on a number of different areas of knowledge including past experience and databases collected and collated over the years. The so-called homology assumption asserts that criminals who exhibit similar crime scene actions have similar background characteristics. (Doan and Snook, 2008, p. 61). In practice this means that investigators in a case of rape, for example, will go on the assumption that there is a positive linear relationship between the similarities of the crime scene actions and the corresponding similarities in the background characteristics for a sample of rapists. Any inferences that are made are deliberately not absolute statements, but are based on likelihood and similarity: It’s certainly possible for some characteristics to be consistent or homologous, and indeed this can be demonstrated in some cases. However, it is not a reasonable assumption in every case or even in most cases. (Turvey, 2008, p. 540) Additional factors such as drug or alcohol use and mental illness with or without adequate medication can affect the offender’s behaviour in unpredictable ways, causing a depart at times from his or her enduring characteristics. Because of these variables, some of which cannot be known by