The first is interpersonal coherence, which proposes that actions performed by criminals make sense within the criminal's own psychology. For instance, the criminal will select victims that are consistent with the important characteristics of people that are important to the offender. The second approach is the significance of time and place. The locations the offender chooses in which to commit the offences will usually have some kind of significance to the offender, people are unlikely to rape in an area unfamiliar to themselves as this is a crime of control, and the offender will not feel in complete control in unfamiliar surroundings.
The third approach, criminal characteristics, involves looking at crimes and offenders, seeing if differences can lead to classifications of offenders into categories and subcategories. Canter does not actually provide an explanation of such classification, but one attempt to do this has been the FBI Classification Manual. Douglas and Olshaker (1995) state 'we set about to organise and classify serious crimes by their behavioural characteristics and explain them in a way that a strict psychological approach such s the DSM has never been able to'.
(p. 346). Canter (1994) is quite critical of the FBI approach, especially in the organised and disorganised dichotomies used by the FBI, arguing that there is too much overlap between the two categories for it to be helpful and that they have no theoretical backing. The fourth approach criminal career seeks to take advantage of the observation that criminal do not change the way in which they commit crimes throughout their criminal careers, although they may escalate the crimes. The fifth approach is that of forensic awareness.
When a serial offender takes steps to cover his tracks, such as forcing the rape victim to take a bath, or combing her pubic hair to remove any traces of the perpetrator, it is a clear sign that he has had some previous contact with the police. This 'should' be a direct indication of the type of contact the offender has had with the police and 'should' therefore narrow down the search. While this has been a fairly brief overview of some of Canter's suggestions, one particular area, that of space and time has received a reasonable amount of attention and has been empirically tested.
Wilson et al (1997) reports that the 'circle hypothesis' (as it is referred to in Canter, 1994) is one of the more prominent of the IP theories. This approach is built upon the hypothesis that serial killers tend to operate on familiar surroundings, in a recent paper, Goodwin and Canter (1997) investigated the spatial behaviour of 54 serial killers in the United States, each of which had killed at least ten times. They found in their sample that the serial killers used in their sample were likely to encounter and abduct nearly all of their victims close to their own home.
The offender would then travel some distance, usually in a different direction for each offence, to dump the body. They also found, however, as the number of offences progressed, the offender was more likely to dump the bodies close to home, reflecting perhaps a growing confidence with his ability to remain undetected. While the overall paradigm itself has not been empirically tested, many of the theories that contribute to IP have, in one example Canter and Kirby (1995) look at the conviction history of child molesters.
This study investigated the validity of the common assumption that child molesters will have a history of sexually deviant behaviour assaults on children, and that these men will escalate their offending from minor to more serious sexual offences. Interestingly, they found that these assumptions, which are often held by police officers, had no empirical basis. They found that these offenders were more likely to have had convictions for theft and burglary, and violent offences than for prior minor sexual offences.
They also found that there was little evidence to suggest escalation from less serious offences. For example, very few men who were child molesters had any history of indecent exposure. Unlike the CSA, investigative psychology was designed from the beginning with science in mind, but this does not mean that it is a science within itself. Canter and his followers have attempted to use established psychological principles and research methodology in order to create a discipline that is empirically sound and open to peer review.
IP has a great deal of potential to become a science, but it still has a long way to go before it will be recognised as a discipline in itself. Wilson et al (1997) claims that one of the main problems with the IP approach to profiling is that it does not actually tell us anything new, except to prose new avenues to explore. This is probably a some what extreme view, as applying the application of psychosocial knowledge to criminal investigation potentially has great value. Even within Britain, Canter is not without his critics.
Britton, Copson, Bakcock, and Boon (1997) state 'it seems to have been assumed by some observers that Canter's is the only systematic approach to profiling in use in Britain, not least because he says so'. Britton and his colleagues, proponents of the DE model of profiling claim that statistical approaches to profiling, such as is used in IP, are only reliable so long as the data set that they are based upon is reliable. Examples of profiling that may or may not have worked.
The guardian on October 94 wrote in an article entitled 'When you ask why, you know who', by John Grace in which he states that in fact that public's reputation of offender profiling was severely damaged by the police's over reliance on its use in the Rachel Nickell murder case. In the Observer in an article entitled 'Warning Britton can seriously damage your health'. The journalist believed that the murder case was a complete disaster and that the police had no hard evidence beyond the fact that Colin Stagg lived near the common and was a bit weird.
The police turned to Paul Britton a psychologist and gave him control of the case. Britton tried to trap Stagg in to confessing that he had in fact killed Rachel Nickell, to an undercover policewoman. Stagg repeatedly denied any such claims, even with the threat of the police woman ending the relationship with him. This evidence would suggest that in fact Britton 'got it horribly wrong' and the case against Colin Stagg was thrown out of court. Britton replies in practice that although offender profiling may help the police, there is a danger in overstating its importance.
Mostly (and Britton does not pretend otherwise) the case is solved by traditional policing and scientific methods. In his first big case Britton drew up a pretty accurate portrait of the killer of school girl Dawn Ashworth, but the murder was caught by a combination of DNA testing and a chance remark in a pub. Britton has been involved in a lot of headline cases, including the Abbie Humpheries baby snatching, The James Bulger killing, (but would he have found these killers had there not been video evidence) and the Fred and Rosemary West's murders.
However the failure in the Colin Stagg case appears to be the only prominent mention in reports, in fact the reporters suggest that anyone associated with it would never be taken seriously again. Wilson and Soothill, (1996) suggest that the running feud between Canter and Britton has made it difficult to state how objective the assessments are of each other, and in some ways they clearly refute the approach taken by the other.