An Empirical Analysis of 30 Years of U.S. Juvenile and Adult Sexual Homicide Offender Data: Race and Age Differences in the Victim–Offender Relationship

Abstract: Little is known about the racial patterns of crimes committed by sexual homicide offenders (SHOs). This study examined race and age influences on victim–offender relationship for juvenile and adult SHOs. A large sample (N = 3868) from the Supplemental Homicide Reports (1976–2005) was used. Analyses of victim–offender patterns included examining victim age effects (child, adolescent, adult, and elderly). The findings revealed several race‐ and age‐based differences. Black offenders were significantly overrepresented in the SHO population. This finding held for juveniles and adults independently. White SHOs were highly likely to kill within their race, “intra‐racially” (range 91–100%) across four victim age categories, whereas Black SHOs killed both intra‐racially (range 24–82%) and inter‐racially (18–76%), with the likelihood of their killing inter‐racially increasing as the age of the victim increased. This study underscores the importance of considering victim–offender racial patterns in sexual murder investigations, and it offers practical implications for offender profiling.     

Juvenile and Adult Offenders Arrested for Sexual Homicide: An Analysis of Victim–Offender Relationship and Weapon Used by Race*

Abstract: Limited information is available on racial offending patterns of sexual homicide offenders (SHOs). This study used a 30‐year U.S. Supplementary Homicide Reports sample of SHOs arrested in single‐victim situations (N = 3745). The analysis strength was used to determine whether the findings yielded meaningful patterns for offender profiling. Several important findings emerged for the juvenile offenders. Juvenile White SHOs were likely to target victims with whom they shared a mutual relationship. In contrast, Black juveniles were equally likely to murder strangers and those with whom they had prior and familial relationships. Notably, no juvenile Black SHOs were arrested for murdering intimate partners. Juvenile White SHOs were twice as likely to use edged weapons as their Black counterparts. Black juveniles, conversely, were more likely than White juveniles to use personal weapons. Beyond these findings, known victim–offender relationships and weapon used may not have significant utility for investigators in identifying the SHO race, even after controlling for offender age. Limitations and future directions are discussed.     

Homicides with Mutilation of the Victim's Body

Abstract:  Information on homicide offenders guilty of mutilation is sparse. The current study estimates the rate of mutilation of the victim's body in Finnish homicides and compares sociodemographic characteristics, crime history, life course development, psychopathy, and psychopathology of these and other homicide offenders. Crime reports and forensic examination reports of all offenders subjected to forensic examination and convicted for a homicide in 1995–2004 ( n  = 676) were retrospectively analyzed for offense and offender variables and scored with the Psychopathy Check List Revised. Thirteen homicides (2.2%) involved mutilation. Educational and mental health problems in childhood, inpatient mental health contacts, self-destructiveness, and schizophrenia were significantly more frequent in offenders guilty of mutilation. Mutilation bore no significant association with psychopathy or substance abuse. The higher than usual prevalence of developmental difficulties and mental disorder of this subsample of offenders needs to be recognized.     

The development of a filter model for prioritising suspects in burglary offences

Abstract

This paper discusses the development of a filter model for prioritizing possible links in dwelling burglary. The filters utilize the central aspects of crime scene information that is available and accessible to investigators in burglary, namely geo-spatial, temporal, behavioural, and dwelling information. The proposed filters were analysed using a sample of 215 dwelling burglaries committed by 43 serial burglars (i.e. 5 offences each) in order to determine the sequence in which the filters should be considered in prioritizing possible linked offences. The results indicated that the following order (i.e. better performance to worse performance) was most effective at linking offences, utilizing: (1) geo-spatial information, (2) temporal aspects, (3) behavioural information and, lastly, (4) dwelling characteristics. Specifically, the results indicated that offences in close proximity to one another should be given priority. Further, any offence occurring within a 28-day span before or after the index offence should be given priority. The paper argues that behavioural and dwelling characteristics are less effective for linking than geo-spatial and temporal information because the former two aspects are influenced significantly by situational and contextual cues on offender decision-making.     

The Motivation Behind Serial Sexual Homicide: Is It Sex,Power, and Control,or Anger?*

Controversy exists in the literature and society regarding what motivates serial sexual killers to commit their crimes. Hypotheses range from the seeking of sexual gratification to the achievement of power and control to the expression of anger. The authors provide theoretical, empirical, evolutionary, and physiological support for the argument that serial sexual murderers above all commit their crimes in pursuit of sadistic pleasure. The seeking of power and control over victims is believed to serve the two secondary purposes of heightening sexual arousal and ensuring victim presence for the crime. Anger is not considered a key component of these offenders' motivation due to its inhibitory physiological effect on sexual functioning. On the contrary, criminal investigations into serial sexual killings consistently reveal erotically charged crimes, with sexual motivation expressed either overtly or symbolically. Although anger may be correlated with serial sexual homicide offenders, as it is with criminal offenders in general, it is not causative. The authors further believe serial sexual murderers should be considered sex offenders. A significant proportion of them appear to have paraphilic disorders within the spectrum of sexual sadism. "sexual sadism, homicidal type" is proposed as a diagnostic subtype of sexual sadism applicable to many of these offenders, and a suggested modification of DSM criteria is presented.     

Sequential angulation,spatial dispersion and consistency of distance attack patterns from home in serial murder,rape and burglary

Abstract

Three related measures of spatial movement (sequential angulation, spatial dispersion and consistency of distance in attack target) were compared across three serial offence types: serial homicide (n=35), serial rape (n=41) and serial burglary (n=30). In each case, each offender had committed at least five offences. “Spatial dispersion”, defined as the extent to which an offender distributes his offences across either a focused or relatively more evenly distributed area, revealed that burglary was less evenly distributed (i.e. more focused) than rape and murder. “Sequential angulation”, defined as the degree of rotational movement around the home of the offender from one offence to the next, revealed that serial murderers have higher angulation scores than do rapists who, in turn, have higher angulation scores than burglars. Lastly, a comparison of the offender's consistency in the relative distance travelled from home to each attack site (“consistency of distance in attack target”) was relatively similar across the three groups. This was despite the comparison of different serial offence types from disparate geographical areas. The supposition that differences in dispersion and sequential angulation scores across crime types are related to the perceived risk of the crime has been confirmed. The specificity and the mobility of the targets are also discussed.     

Murderer vs investigator: factors influencing the resolution of sexual homicide cases

ABSTRACT

The objective of this study was to identify the factors associated with the duration of criminal investigations and determine whether these factors influence the seriality of sexual murderers. To this end, data on the investigation of 62 sexual homicides (homicides committed by a serial sexual murderer = 24; homicides committed by a nonserial sexual murderer = 38), were analyzed. Organized behaviors, typical of serial sexual murderers, were not all associated with a longer criminal investigation. However, it was possible to develop a model of the duration of investigations, and predict the seriality of sexual murderers, by taking into account the decisions of murderers and investigators.     

The Prediction of Young Homicide and Violent Offenders

Aim was to investigate a range of potentially modifiable risk factors for boys in late childhood for later violence and homicide convictions. Boys from the Pittsburgh Youth Study (N = 1,517) were measured through self-reports and official records in late childhood (ages 11–13) on a large number of potentially modifiable risk factors, and were followed up in juvenile and adult criminal records in terms of violence and homicide. Predictors of conviction for homicide largely overlapped with predictors of conviction for violence. Twenty three out of 28 possible risk factors significantly predicted later violence convictions. Regression analysis identified four significant modifiable risk factors in late childhood for any violent offenders: physical abuse, parental stress, bad friends and low school motivation. The higher the number of early risk factors, the higher the probability of later conviction for violent offenses including homicide. The discussion focus on single-, and multi-modal interventions in late childhood to reduce later violence and possibly homicide.     

The Application of Missing Data Estimation Models to the Problem of Unknown Victim/Offender Relationships in Homicide Cases

Homicide cases suffer from substantial levels of missing data, a problem largely ignored by criminological researchers. The present research seeks to address this problem by imputing values for unknown victim/offender relationships using the EM algorithm. The analysis is carried out first using homicide data from the Los Angeles Police Department (1994-1998), and then compared with imputations using homicide data for Chicago (1991-1995), using a variety of predictor variables to assess the extent to which they influence the assignment of cases to the various relationship categories. The findings indicate that, contrary to popular belief, many of the unknown cases likely involve intimate partners, other family, and friends/acquaintances. However, they disproportionately involve strangers. Yet even after imputations, stranger homicides do not increase more than approximately 5%. The paper addresses the issue of whether data on victim/offender relationships can be considered missing at random (MAR), and the im-plications of the current findings for both existing and future research on homicide.     

Crime Scene Behaviors and Characteristics of Offenders with Mental Illness: A Latent Class Analysis

The current study aimed to identify distinct types of crime scene behaviors based on the criminal planning and motivation of offenders with mental illness in South Korea. Furthermore, our study examined the relationships between the identified types of crime scene behaviors in terms of the offenders’ sociodemographic characteristics, modus operandi, and types of mental illness. Utilizing latent class analysis, the associations between crime scene behavior types and offender characteristics such as demographic factors, crime scene actions, and criminal information were empirically investigated. In particular, based on a sample obtained from a national police database of offenses committed between 2006 and 2014, four offense groups were identified: (i) instrumental–planned, (ii) instrumental–unplanned, (iii) expressive–unplanned, and (iv) hybrid. Additionally, significant relationships were found between offense styles and offender characteristics as well as criminal backgrounds. The findings suggest that mental disorders influence the types of actions exhibited by offenders during the commission of their crime. The results are discussed in terms of their theoretical and practical utility to criminal investigation.     

Exploring the criminal histories of stranger sexual killers

Although sexual homicide is receiving increasing research attention, few studies have examined the criminal histories of sexual killers in any detail. This study examined the criminal histories of 81 British stranger sexual killers to determine whether they were generalist, specialists or both and whether their criminal histories reflected violent, sexual, marginality and over control pathways. Results found most stranger sexual killers were generalist offenders and sexual homicide was part of a varied criminal repertoire and non-sexual crimes predominate. This ‘antisocial orientation’ means future offending may not be limited to sexual violence. Criminal histories reflected the violent, sexual, marginality and over control pathways, but offenders in the violent pathway were more criminally orientated. The clinical and investigative implications of these findings were considered as they suggest knowledge of the criminal histories of stranger sexual killers is an important consideration for criminal justice professionals.     

Multidimensional scaling and the analysis of sexual offence behaviour: a reply to Sturidsson et al.

Abstract

Sturidsson et al. (Psychology, Crime & Law, 12, 221–230, 2006) published an article on the replicability of early multidimensional scaling (MDS) behavioural research by Canter and Heritage (Journal of Forensic Psychiatry, 1, 185–212, 1990). Sturidsson et al. were unable to find a ‘readily apparent, simple interpretation’ of their MDS solution and therefore suggested that the MDS approach may be flawed as a device for interpreting sexual assault. The current paper explains how the methods employed by Sturidsson et al. represent an incorrect use of MDS, specifically in their input of Jaccard similarity data into the MDS (ALSCAL) procedure in SPSS as opposed to the correct MDS (PROXSCAL) procedure. A comparative example is used to illustrate how adopting the ALSCAL procedure will result in an inverse MDS solution, where objects appearing closer together are more dissimilar, making interpretation of the MDS plot meaningless in this context. The current paper discusses this methodological flaw in greater depth and in the context of behavioural investigative research using MDS in general. It concludes with some general guidelines in utilizing the MDS procedure in SPSS specific to criminal profiling research.     

A systematic review of the literature comparing male non-serial sexual killers and sexual aggressors: examining homogeneous and heterogeneous characteristics of these groups

ABSTRACT

This systematic review considers what is known about the characteristics of sexual killers and sexual aggressors. The aim was to identify which characteristics have consistently been shown to be similar (homogeneous) and which are different (heterogeneous) across these two groups. Ten studies, including approximately 300 sexual killers, were analysed. Only studies where the samples were directly compared and where sexual killers were male, predominantly non-serial and perpetrated against adult female victims were included. Results indicate that levels of loneliness and anger appear to be more prevalent in the sexual killer sample while mental health disorders, criminal history, family structure and history of sexual abuse as well as some crime scene behaviours seem to be similar across the two groups. The results of this review have also highlighted some methodological problems inherent to these types of studies and these issues are discussed from the perspective of improving research on these crimes.     

Body Disposal Patterns of Sexual Murderers: Implications for Offender Profiling

Offender profiling postulates that crime scene behavior should predict certain offender characteristics. The aim of this study is to investigate the relationship between offender characteristics, situational factors, and body disposal patterns. Sequential logistic regression analysis on a sample of 85 sexual murderers shows that those who were in a relationship at the time of the crime and who present organized psychological characteristics are more likely to move the victim’s body after the homicide. However, when the victim is older and a conflict with the offender occurred prior to the crime, the body is more likely to be left at the crime scene. Implications for offender profiling are discussed in light of the results.

Aggressive hybristophilia in men and the affect of a female serial killer

A case is presented of hybristophilia – attraction and sexual arousal to the criminal acts of another – in men which, to date, is a phenomenon that has not been documented. A sexually motivated female serial killer recruited the help of three male accomplices to aid her in her crimes and avoid police detection. The men became enthralled by the killer, falling ‘under her spell’, and willingly aided her, in varying degrees, in locating and disposing of victims. The behaviour of those men is explored here and the scant literature base on hybristophilia is expanded.     

Evaluation of the assessment and treatment of a child sex offender: A case study

Abstract

There is indisputable necessity for engaging child sex offenders in effective therapy to reduce recidivist rates. However, it is becoming increasingly recognised that, to do this, more contemporary psychological methods of treatment are being utilised instead of, or as well as, imprisonment.

To establish what constitutes effective therapy requires the constant search for new and successful treatments. To achieve this, it is advantageous to follow preexisting successful methods of treatment but to acknowledge that therapy must be adapted according to an individual's unique presenting difficulties and therapeutic needs.

This paper details assessment techniques, evaluation of psychological dysfunctions, the therapy plan and treatment outcome of a convicted child sex offender. Specifically, Mr X's background history, psychological dysfunctions and progress, using a functional analysis approach, are examined in detail with critical review of the therapeutic intervention.     

Paths to destruction: the lives and crimes of two serial killers

Although research into the phenomenon of serial murder has revealed that serial killers frequently do not fit the initially described paradigm in terms of their physical and psychological profiles, backgrounds, and motives to kill, the media continues to sensationalize the figures of such killers and the investigators who attempt to analyze them on the basis of aspects of their crimes. Although the so-called "typical" profile of the serial murderer has proven accurate in some instances, in many other cases the demographics and behaviors of these killers have deviated widely from the generalized assumptions. This report details two unusual cases in which five and eight murders were committed in upstate New York. The lives and crimes of these offenders illustrate the wide spectrum of variations in the backgrounds, demographics, motivations, and actions witnessed among serial murderers, and highlight the limitations and dangers of profiling based on generalities.     

Piquerism in homicide: A knife wound analysis of a sexually motivated serial killer

As part of a wider research project into paraphilic disorders and homicide, a case is presented of a piquerist who achieved sexual satisfaction through the infliction of stabbing wounds. Against a background of sexual domination with willing and unwilling sexual partners, the offender stabbed four men to death. A study of the resulting autopsy reports, in association with the offender's testimony and crime scene documentation, was undertaken to discern a piquerist crime scene signature. An excessive number of stabbing wounds, the targeting of sexual areas, and a variation in wound size and depth were found to be evidence of piquerism. Although there was opportunity to commit a sexual assault upon victims, the preference was to penetrate them with a knife. It is contended that, even without any evidence of sexual assault at a crime scene, a knife wound analysis can reveal a sexual motivation in some cases of homicide.