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A multivariate model of sexual offence behaviour : developments in 'offender profiling'. I. ABSTRACTThe extrapolation of characteristics of criminals from information about their crimes, as an aid to police investigation, is the essence of 'profiling'. This paper proposes that for such extrapolations to be more than educated guesses they must be based upon knowledge of (1) coherent consistencies in criminal behaviour and ( 2 ) the relationship those behavioural consistencies have to aspects of an offender available to the police in an investigation. Hypotheses concerning behavioural consistencies are drawn from the diverse literature on sexual offences and a study is described of 66 sexual assaults committed by 27 offenders against strangers. Multivariate statistical analyses of these assaults support a fivecomponent system of rapist behaviour, reflecting modes of interaction with the victim as a sexual object. The potential this provides for an eclectic theoretical basis to offender profiling is discussed.

A model of individual sexual offenders' spatial activity was developed based upon 45 British male sexual assaulters who had committed at least two assaults.

It is hypothesized that there will be behavioural consistencies in the actions of arsonists when committing a crime that characterize them. The themes underlying these observable differences can be used to help us understand the nature of the offence. With arson, one such observable difference is hypothesized to relate to the target or focus of the attack. The study tested whether consistencies could be found that distinguish person‐oriented from object‐oriented arsons. A second proposed facet of arson actions relates to the motivational category underlying the act, being either instrumental or expressive. It was also hypothesized, therefore, that there would be a distinction in the arson actions between fires set for a clear instrumental purpose, and those which may be regarded as emotional acting‐out. The hypothesis that these four themes would differentiate arsonists was tested by analysing 175 solved arson cases from across England. The case files were content analysed to produce 42 behavioural variables taken from both the crime reports and witness statements. In order to test the hypotheses of differentiation a smallest space analysis was carried out. The results support this framework giving rise to four distinct themes to arson from which scales with reasonable alpha scores could be derived. Two relate to expressive acts, (a) those that are realized within the arsonist's own feelings, being analogous to suicide, and (b) those that are acted on objects, like the burning of symbolic buildings. The other two relate to instrumental acts, (c) those that are for personal indulgence, similar to personal revenge, and (d) those that have an object focus such as hiding evidence from a crime. A further test of the validity of these four themes was to examine the typical characteristics of the people who committed the different types of arson. Four scales of arsonists' characteristics were developed. These were found to have appropriate, statistically significant correlations with the four themes. The implications of these findings for understanding the varieties of arson as revealed through the actions that occur are discussed, as well as the implications for arson investigations. It is speculated that this framework may provide a general model for considering a wide range of crimes.

It is hypothesized that stranger rape victim statements will reveal a scale of violation experienced by the victim, ranging from personal violation, through to physical violation, and finally, at the most extreme level, sexual violation. It is also hypothesized that offences can be differentiated in terms of one of four themes: hostile, controlling, stealing, or involving. To test these hypotheses, crime scene data from 112 rapes were analyzed by the multi-dimensional scaling procedure Smallest Space Analysis. The results provide empirical support for a composite model of rape consisting of four behavioral themes as different expressions of various intensities of violation. The results also suggest that stranger rapes may be less about power and control than about hostility and pseudo-intimacy. The proposed model has implications for the classification of rape, the investigation of sexual crimes, and the treatment of victims.

The literature on “offender profiling” suggests that different “styles” of homicide will reflect differences in the background characteristics of the offender. To test this suggestion, hypotheses were drawn from studies of aggression to propose that murder crime scenes would reveal stylistic distinctions in the role of the aggression in the offense. It was further hypothesized that these distinctions would be clearest for those crime scene indicators that reflect the instrument (cognitive) actions that shape the offense rather than the more expressive (impulsive and emotional) components. Hypotheses about associated offender characteristics were also deduced on the assumption that the murder scene theme revealed the killers' typical styles of interpersonal transaction. To test these hypotheses MDS analyses were carried out on the crime scene and offender characteristics derived from 82 single offender, single victim stranger homicides. A multivariate structure resulted, including all three hypothesized styles, allowing 65% of the cases to be assigned to unique styles and a further 36% to be assigned to appropriate hybrids. Offender characteristics related in the anticipated way to the different crime scene styles, providing a basis for law enforcement inferences about offenders in stranger murders. Copyright © 1999 John Wiley & Sons, Ltd.

Purpose. The psychological hypotheses that form the foundations for 'Offender Profiling' are identified and the research that has tested them is reviewed.Argument. 'Offender profiling' is taken to be the derivation of inferences about a criminal from aspects of the crime(s) s/he has committed. For this process to move beyond deduction based on personal opinion and anecdote to an empirically based science a number of aspects of criminal activity need to be distinguished and examined. The notion of a hierarchy of criminal differentiation is introduced to highlight the need to search for consistencies and variations at many levels of that hierarchy. However, current research indicates that the key distinctions are those that differentiate, within classes of crime, between offences and between offenders,. This also leads to the hypothesis of a circular ordering of criminal actions, analogous to the colour circle, a 'radex'.The radex model, tested using Multi-Dimensional Scaling (MDS) procedures, allows specific hypotheses to be developed about important constituents of criminal differentiation:Salience; MDS analyses reveal the importance of the frequency of criminal actions as the basis on which the significance of those actions can be established. Inference; under limited conditions it is possible to show associations between the characteristics of offenders and the thematic focus of their crimes. Models of DifferentiationIn general these results provide support for models of thematic consistency that link the dominant themes in an offender's crimes to characteristic aspects of his/her lifestyle and offending history. Implications.Much of what passes for 'offender profiling' in practice and as reported in the factual and fictional media has no basis in empirical research. However, there are some promising results emerging in some areas of study. These results are most likely to be of value to police investigations when incorporated into decision support systems and the training of police officers. The results do also provide new insights into the psychology of crime.

The dichotomous classification of serial killers into either Organized or Disorganized is widely cited and utilized. Yet only one, small-scale, empirical test of such a model can be found in the scientific literature and that study is open to a number of serious challenges. Despite many obvious weaknesses in the clarity and reliability of this typology it is commonly cited as a basis for the production of 'offender profiles' to help police investigations and has, on occasion, formed the foundation of some prosecution arguments in murder trials.Murder scene information, available from law enforcement agencies provides the potential for systematic analysis that can be used to test the assumptions underlying the organized/disorganized dichotomy. Well-established psychometric procedures provide a basis for testing the model by examining the underlying structure within the co-occurrence of those crime scene actions proposed as crucial constituents of the model.As a first step in testing this model the patterns of co-occurrence of 39 aspects of serial killings were identified from the crime scenes of 100 murders committed by 100 US serial killers.This information was subject to a multidimensional scaling procedure that examined the cooccurrence of every one of the 39 aspects with every other. This analysis revealed that there are no discrete sub-sets of offence characteristics that can be regarded as distinctly related to the organization or disorganization of the killings. Instead there appears to be a sub-set of organized features typical of most serial killings with disorganized features being much more rare and not cooccurring as a distinct type. The general implications for testing typologies offered to support expert opinion and to develop our understanding of crime are discussed. The Organized/ Disorganized dichotomy is one of the most widely cited classifications of violent, serial offenders. Although first introduced by the special agents of the FBI Training Academy at Quantico in an examination of lust and sexual sadistic murders (Ressler, Burgess, Douglas, Hartman and D'Agostino, 1986) the distinction has since been put forward to differentiate all sexual homicides and also types of arson in Douglas, Burgess, Burgess, and Ressler's (1992) Crime Classification Manual. These authors make the distinction between Organized and Disorganized offenders on criteria that they claim can be drawn from an examination of the crime scene, the victim, and forensic reports. Ressler et al (1986) claim that '…facets of the criminal's personality are evident in his offense. Like a fingerprint, the crime scene can be used to aid in identifying the murderer' (pg. 291). They propose that offenders' behavioral and personality characteristics can be determined from evidence at a crime scene ). This 'fingerprint' is proposed to take one of two distinct forms, either organized or disorganized. The organized offender is described as leading an orderly life that is also reflected in the way he commits his crimes. Highlighting ...