Swedish rape offenders — a latent class analysis

Sweden has witnessed an increase in the rates of sexual crimes including rape. Knowledge of who the offenders of these crimes are is therefore of importance for prevention. We aimed to study characteristics of individuals convicted of rape, aggravated rape, attempted rape or attempted aggravated rape (abbreviated rape+), against a woman ≥18 years of age, in Sweden. By using information from the Swedish Crime Register, offenders between 15 and 60 years old convicted of rape+ between 2000 and 2015 were included. Information on substance use disorders, previous criminality and psychiatric disorders were retrieved from Swedish population-based registers, and Latent Class Analysis (LCA) was used to identify classes of rape+ offenders. A total of 3 039 offenders were included in the analysis. A majority of them were immigrants (n = 1 800; 59.2%) of which a majority (n = 1 451; 47.7%) were born outside of Sweden. The LCA identified two classes: Class A — low offending class (LOC), and Class B — high offending class (HOC). While offenders in the LOC had low rates of previous criminality, psychiatric disorders and substance use disorders, those included in the HOC had high rates of previous criminality, psychiatric disorders and substance use disorders. While HOC may be composed by more “traditional” criminals probably known by the police, the LOC may represent individuals not previously known by the police. These two separated classes, as well as our finding in regard to a majority of the offenders being immigrants, warrants further studies that take into account the contextual characteristics among these offenders.

Key points

• Rape, aggravated rape, attempted rape or attempted aggravated rape (rape+) are increasing in Sweden.
• The majority of those convicted of rape+ are immigrants.
• LCA identifies two classes of rape+ offenders: LOC and HOC.

     

Juvenile sex offenders: a complex population

Individuals who engage in sexual offending behavior represent a heterogeneous population. Recent research has found some success in categorizing sexual offenders based on a number of variables, particularly the type of victim. For example, differences have been found between those offenders who victimize adults when compared with those who victimize children. However, the research in this area has been conducted predominantly with adult samples. As the adult sex offender literature has progressed, it has become evident that risk assessment, treatment effectiveness, and risk management are dependent on such offender characteristics. Unfortunately, the relevance to juveniles of characteristics deemed to be important with adult sex offenders is limited due to the complexity of developmental processes, particularly with respect to mental disorders and personality formation. As such, the formulation and implementation of treatment and risk management strategies that will be effective with juvenile sex offenders are challenging. The goal of this paper is to review some of the complexities inherent in the juvenile sex offender population by focusing on specific areas of complication, including: classification systems, comorbid paraphilias and other mental illnesses, and maladaptive personality traits.     

The RECON typology of stalking: reliability and validity based upon a large sample of North American stalkers

A new typology of stalking, RECON (relationship and context-based), is proposed, based upon the prior relationship between the pursuer and the victim, and the context in which the stalking occurs. The static typology yields four groups: Intimate, Acquaintance, Public Figure, and Private Stranger. The typology was tested on a large (N = 1005) nonrandom sample of North American stalkers gathered from prosecutorial agencies, a large police department, an entertainment corporation security department, and the authors' files. Interrater reliability for group assignment was 0.95 (ICC). Discriminant validity (p < 0.01) was demonstrated on a variety of demographic, clinical, pursuit, threat, and violence characteristics among and between groups. Findings confirm and extend the work of other researchers, most notably the very high risk of threats and violence among prior sexually intimate stalkers, the very low risk of threats and violence among public figure (celebrity) stalkers, and the negative relationship between stalking violence and psychosis.     

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.     

DNA recovery after sequential processing of latent fingerprints on copy paper

Forensic examiners must determine whether both latent fingerprint development and DNA profiling can be performed on the same area of an evidence item and, if only one is possible, which examination offers the best chance for identification. Latent fingerprints can be enhanced by targeting different components of fingerprint residues with sequential chemical treatments. This study investigated the effects of single-reagent and sequential latent fingerprint development processes on downstream DNA analysis to determine the point at which latent fingerprint development should be stopped to allow for DNA recovery. Latent fingerprints deposited on copy paper by one donor were developed using three sequential processes: 1,8-diazafluoren-9-one (DFO) → ninhydrin → physical developer (PD); 1,2-indanedione-zinc (IND-Zn) → ninhydrin → PD; and IND-Zn → ninhydrin → Oil Red O (ORO) → PD. Samples were examined after the addition of each chemical treatment. DNA was collected with cotton swabs, extracted, quantified, and amplified. DNA yields, peak heights, number of alleles obtained, and percentage of DNA profiles eligible for CODIS upload were examined. DNA profiles were obtained with varying degrees of success, depending on the number and type of treatments used for latent fingerprint development. The treatments that were found to be the least harmful to downstream DNA analysis were IND-Zn and IND-Zn/laser, and the most detrimental treatments were DFO, DFO/laser, and PD. In general, as the number of treatments increase, the opportunities for DNA loss or damage also increase, and it is preferable to use fewer treatments when developing latent fingerprints prior to downstream DNA processing.     

Development of a GC-MS method for the simultaneous analysis of latent fingerprint components

Latent fingerprint residue is a complex mixture of organic and inorganic compounds. A full understanding of the composition of this mixture and how it changes after deposition is lacking. Three solvent systems were compared for the simultaneous extraction and derivatization with ethyl chloroformate of selected amino and fatty acids from a nonporous substrate (Mylar for subsequent analysis by gas chromatography-mass spectrometry. A solvent system comprised of sodium hydroxide, ethanol, and pyridine was found to be the most effective. This method was applied to the analysis of latent fingerprint residue deposited on Mylar and preliminary data are presented. Twelve amino acids (e.g., serine, glycine, and aspartic acid) and 10 fatty acids (e.g., tetradecanoic, hexadecanoic, and octadecanoic acids) were identified. The potential application of this method to further the understanding of latent fingerprint chemistry has been demonstrated.     

Latent Profile Approach to Duration of Stalking

Abstract: Stalking behavior and victim–stalker relationship are often the principal known factors in a stalking case. Thus, they are of great importance when trying to identify factors contributing to stalking duration. The present study aims to identify distinct subgroups of stalking victims based on measures of behavioral stalking dimensions. These victim subgroups, stalking dimensions, and victim–stalker relationship are examined in relation to stalking duration. Using a sample of 137 university students, latent profile analysis (LPA) revealed five distinct victim subgroups based on stalker behavior dimensions: surveillance, low‐profile, social lurker, wide scope, and baseline stalkers. The subgroups were significantly related to stalking duration and explained a considerable amount of the variance along with the stalking dimensions and victim–stalker relationship. Connections to stalking literature and utility of person‐orientated methods in stalking research are discussed.     

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.     

De Novo Advanced Adult‐Onset Offending: New Evidence from a Population of Federal Correctional Clients

Adult antisocial behavior is almost always predated by delinquency during childhood or adolescence; however, there is also evidence of adult‐onset criminal offending. This study examined this controversial subgroup of offenders using self‐reported and official data from a total population of federal correctional clients selected from the Midwestern United States. Difference of means t‐tests, chi‐square tests, and logistic regression models found that 11.7% of clients had an adult onset of offending and 2.7% of clients (n = 23) had an onset occurring at age 60 years or older. This group—introduced as de novo advanced adult‐onset offenders—had high socioeconomic status, mixed evidence of adverse childhood experiences, and virtually no usage of drugs with the exception of alcohol. These offenders were primarily convicted of social security and white‐collar crimes and evinced remarkably low psychopathology and criminal risk. More research is needed to replicate the phenomenon of de novo advanced adult‐onset offending.     

Visualization of latent fingermark corrosion of brass, climatic influence in a comparison between the U.K. and Iraq

Through a comparison of fingermark sweat corrosion of α phase brass in both the U.K. and Iraq, we show how samples from Iraq have improved fingermark corrosion over U.K. samples that require no additional enhancement prior to visualization. Over 50% of Iraqi samples produced fingermark corrosion with full ridge detail compared with 0% from the U.K. X-ray photoelectron spectroscopy analysis of the fingermark corrosion products showed that Iraqi samples exhibit more dezincification with the Zn:Cu ratio averaging 1:1.82 compared with 1:3.07 for U.K. samples. Auger spectroscopy showed the presence of both zinc oxide and copper (I) oxide. No copper (II) was observed on the surface of the corroded brass. Opportunities to exploit the optical properties of these thin film oxides to enhance the visualization of fingermark corrosion are considered, and the potential to use fingermark corrosion of metal as a means of visualizing fingerprints in war zones is discussed.     

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.     

The uniqueness of the human anterior dentition: a geometric morphometric analysis

The analysis of bitemarks has a significant bearing on forensic odontology and has attracted an increasingly sophisticated array of techniques in its evaluation. Two postulates underlie all bitemark analyses: firstly, that the characteristics of the anterior teeth involved in the bite are unique, and secondly, that this uniqueness is accurately recorded in the material bitten. Here, we investigate the question of the uniqueness of the anterior dentition. To do this, we use geometric morphometric techniques based on landmark and semilandmark data. The incisor and canine occlusal surfaces of 50 randomly selected orthodontic casts of young individuals (17-20 years) of both sexes form the material for this study. We analyzed the sizes of these teeth by means of landmark and semilandmark analysis to calculate Procrustes distances between tooth outlines. In order to analyze shape variation among individuals, we carried out principal components analyses on the partial warp scores. These are derived from Partial Procrustes coordinates aligned by means of thin-plate spline decomposition based on the bending energy matrix. The results indicate that there is no sexual dimorphism in the shape of the upper or lower arches. Plots of centroid size and first relative warps show less superposition among individuals than in shape analysis. This means that, when the size and shape are considered together, the difference between arches increases. Procrustes superimposition between the two individuals located most closely (0.0444) and the two most separated (0.1567) along the first axis of relative warp analyses show that individuals are not only differentiated by the relative position of their teeth but also by their arch shape. In conclusion, it appears that the incisal surfaces of the anterior dentition are in fact unique.     

Thermal degradation analysis of amino acids in fingerprint residue by pyrolysis GC-MS to develop new latent fingerprint developing reagents

Conventional development of latent fingerprints is compromised when the prints are decomposed by extreme temperatures, such as those encountered when a weapon cartridge is fired, an improvised explosive device is detonated, and/or in arson cases. Understanding how these extreme temperatures alter the chemical and physical properties of latent fingerprint residue could aid in the discovery of a reagent that could effectively develop these decomposed fingerprints. To mimic scenarios where fingerprints may be exposed to high heat conditions, standards of the five most abundant amino acids in fingerprint residue as well as extracted fingerprint residue were pyrolized under controlled conditions. Compounds identified as pyrolytic decomposition products were 3,6-dimethylpiperazine-2,5-dione (from alanine), maleimide, and 2,5-furandione (from aspartic acid). The pyrograms and selected ion traces show these products to hold promise as indicators of decomposed fingerprint residues and, therefore, may serve as good candidate substrates for a developing reagent.     

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.     

MMPI profiles of males accused of severe crimes: a cluster analysis

Abstract

In studies attempting to classify criminal offenders by cluster analysis of Minnesota Multiphasic Personality Inventory-2 (MMPI-2) data, the number of clusters found varied between 10 (the Megargee System) and two (one cluster indicating no psychopathology and one exhibiting serious psychopathology). The latter results raise doubts about the suitability of the MMPI-2 for classification in forensic settings. The present study aimed at deriving an empirical classification system using cluster analysis of 247 MMPI-2 profiles of pretrial criminal defendants in a forensic psychiatric observation clinic. Results indicated only a ‘non-disturbed’ and a ‘disturbed’ profile, differing on general elevation of MMPI-2 profiles but displaying no qualitatively distinct profiles. The clusters differed on age at admission and first conviction, indicating a late onset of criminal activity for disturbed offenders. Also, the clusters differed significantly on Axis I diagnosis and borderline significantly on Axis II diagnosis. The absence of distinct personality profiles between the clusters suggests restricted usefulness of the MMPI-2 in a forensic context of diverse and severe psychopathology and serious crimes. Either the investigated population is in fact extremely homogeneous, truly comprising only two kinds of offenders, or the types of offenders in these populations are not effectively distinguished by the MMPI-2.     

Nanoscale analysis of the interaction between cyanoacrylate and vacuum metal deposition in the development of latent fingermarks on low-density polyethylene

Vacuum metal deposition (VMD) has been previously demonstrated as an effective development technique for latent fingermarks and in some cases has been shown to enhance prints developed with cyanoacrylate (CA) (superglue) fuming. This work utilizes scanning electron microscopy (SEM) to investigate the interactions of the two development techniques when applied to latent fingermarks on low-density polyethylene. CA is shown to act principally on the eccrine deposits around sweat pores, where polymerization results in long polymer fibrils a few 100 nm in width. Subsequent VMD processing results in additional areas of development, for example, between pores. However, the primary mode of deposition of zinc is by interaction with the polymerized CA, the fibrils of which become decorated with zinc nanoparticles. Areas with limited CA deposition and no significant polymerization are also enhanced with the VMD process, resulting in increased print development.     

Bacterial Profiling of Soil For Forensic Investigations: Consideration of Ex Situ Changes in Questioned and Known Soil Samples

Soil, being diverse and ubiquitous, can potentially link a suspect or victim to a crime scene. Recently scientists have examined the microbial makeup of soil for determining its origin, and differentiating soil samples is well-established. However, when soil is transferred to evidence its microbial makeup may change over time, leading to false exclusions. In this research, “known” soils from diverse habitats were stored under controlled conditions, while evidence soils were aged on mock evidence. Limited quantities of soil were also assayed. Bacterial profiles were produced using next-generation sequencing of the 16S rRNA gene. Overall, known soils stored open at room temperature were more similar to evidence soils over time than were known soils stored bagged and/or frozen. Evidence soils, even as little as 1 mg, associated with the correct habitat 99% of the time, accentuating the importance of considering ex situ microbial changes in soil for its successful use as forensic evidence.     

Compatibility Between Mental Disorder and Mental Capacity: Analysis of a Particular Case of Group Sexual Homicide

Abstract: On the night of August 19, 2000, at the foot of Castel del Monte, an 8‐year‐old girl was brutally murdered. The perpetrators were identified as five young men who captured their victim and sexually abused her. The policemen found the cadaver by following “Mario,” one of the five, who had been discovered lying on the ground, near the castle. Investigation led to demonstrate that the murder was not premeditated. The only desire of the group was to sexually molest the little girl. Mario showed signs of psychiatric pathology and for that he underwent psychiatric evaluation by judicial authorities. Analysis of this case, combined with a criminological and medical‐legal perspective led to conclusions very much different from the expectations of Mario’s defense attorneys. Mario, a marginal figure and seemingly the least intelligent, played the role of group instigator, both in the initiation of sexually abusing the child, as well as in the elimination of an inconvenient witness. However, the group was able to activate Mario’s sadistic fantasies and his sexual perversions, and he ended up in a catalyzing role influencing the behavior of others and realizing what would otherwise remain only fantasies. The circularity of the group allows people like Mario, who are apparently subordinate, to influence the behavior of others. Mario was found to have a mental disorder but it was not sufficient to diminish his personal responsibility related to the crime. In fact, according to Italian judicial code, it is necessary that the motivation for the crime was psychopathological. It was for this reason that, according to Italian law, all of the members of the group were considered to be responsible for the crimes committed and were condemned.