Criminological and Medico-legal Aspects in Homicidal and Suicidal Sharp Force Fatalities

The interpretation of sharp force fatality dynamics may be difficult in some cases, but a contribution to analysis of the phenomenon may be provided by case studies. Therefore, the purpose of our study is focused on identifying, in observed sharp force fatalities, reliable parameters that can differentiate a homicidal and suicidal manner of death, with particular reference to criminological parameters. Data derived from sharp force fatality cases in Padua and Venice from 1997 to 2019, anonymized and collected in Excel, included personal, circumstantial, clinical, and psychopathological–criminological data, as well as crime scene investigation, necroscopic, and toxicological data. Statistical analyses were performed using chi-square and Wilcoxon rank-sum tests. Possible predictors of homicide were analyzed by logistic regression. Six parameters (bloodstains distant from the body, clothing lacerations, hesitation/defense wounds, number of injuries, and potential motives) were significantly different in the two groups (p < 0.05). An independent statistical association between potential motives explaining the crime (p < 0.001; OR 27.533) and homicide on multiple logistic regression analysis was highlighted. The absence of clothing lacerations was inversely related to homicide (p = 0.002, OR 0.092). To the best of our knowledge, this is one of very few Italian studies concerning the differential diagnosis between homicidal and suicidal sharp force fatalities. The dynamics of the event is established in most cases by the integrated evaluation of data from crime scene investigation and the autopsy. Nevertheless, in an atypical scenario, a psychopathological–criminological analysis may provide essential elements, and particular attention should be given to the identification of potential explanatory motives.     

Sharp Force Injury Fatalities: A Retrospective Study (1982–2012) in Brescia (Italy)

A retrospective study was carried out on postmortem examination data of 131 sharp force‐related casualties recorded by the Brescia Institute of Forensic Medicine between 1982 and 2012. The objective was to identify relevant parameters that may be used to distinguish the manner of deaths between homicide, suicide, and accident. The following variables were considered: manner of death; demographic data; scene; type of sharp object; location and numbers of wounds; the presence of hesitation marks/defense wounds; toxicological findings; psychiatric history. There were 92 homicides, 28 suicides, and 11 accidents. Most victims were male, with an average age of 43. Injuries in isolation were present in 9.8% of homicides, in 35.7% of suicides, and in 54.5% of accidents. Most injuries involved the left anterior chest in homicides and the forearms in suicides. This study underlines the importance of a meticulous postmortem examination of injuries on the body and their relationship with other results from the death scene investigation.     

Suicidal or Homicidal Sharp Force Injuries? A Review and Critical Analysis of the Heterogeneity in the Forensic Literature

The differential diagnosis between self-inflicted and nonself-inflicted, suicidal and homicidal, injuries is difficult or impossible in many cases and, above all, cannot be made on the basis of information obtained solely from the autopsy or the medicolegal clinical examination. The purpose of this study is to analyze the literature on suicidal and homicidal sharp force injuries and identify the relevant parameters that may help differentiate between suicidal and homicidal deaths. To achieve this goal, a review of 595 potentially relevant articles was performed. After excluding the nonrelevant papers by screening the titles, all abstracts were reviewed, and articles meeting the inclusion criteria underwent a full-text review. The following parameters were compiled into a table: number of cases, localization of the injuries, and number of injuries. The data were statistically analyzed and compared with those available in the forensic literature. On the basis of the heterogeneity of data revealed by the present review, a simple and short checklist of the parameters that should be included when reporting suicides and homicides by sharp force has been proposed.     

Complex Suicide by Self‐stabbing and Drowning: A Case Report and a Review of Literature

Sharp force injuries and drowning are methods exceptionally combined in complex suicides. We report a challenging case of complex suicide by self‐stabbing and drowning that illustrates the difficulty in discriminating between homicide and suicide in such circumstances of death. The corpse of a young man was found submerged in a river, stabbed nine times with two wounds that had penetrated the thorax and had caused lung injuries and a hemopneumothorax. The postmortem and histological examinations were consistent with a death caused by drowning, but the manner of death still remained undetermined. Police investigation finally concluded to a suicide, although no suicide note had been left and the victim had no underlying diagnosed mental disorder. The parameters that may help distinguish suicide from homicide at the autopsy should be interpreted in light of a thorough forensic investigation to determine the exact manner of death in such a case.     

Sharp Force Homicide in Denmark 1992–2016

Sharp force trauma is a common homicide method. The weapon is typically a knife, which is easily accessible and does not require special skills. We have analyzed all 471 sharp force homicides in Denmark during 1992–2016 with special focus on aspects that are relevant to forensic pathologists, including the distribution of wounds and organ injuries. Most homicides were committed inside with a kitchen knife. The front left thorax was the most common area to be affected by sharp force trauma. In 18.9% of the victims, there was only one sharp injury, the majority on the thorax. The most common trajectory for stab wounds was directly posterior with no deviation to the sides or up/down followed by directly anterior. The heart (including pericardium) and lungs (including hemo- and pneumothorax) had injuries in more than 75% of the victims. 67% of victims were males. Female victims had more sharp force injuries and defense wounds than male victims. Most females were killed in domestic homicides (73.7%), most commonly in partner killings (56.4%). In contrast, many male victims were killed in a setting of nightlife/intoxication (34.0%) most by a friend/acquaintance delivering a few stab wounds. The results clearly show strong sex differences in both victims and offenders. This could be useful for shaping policies and public opinion, and as a route for understanding the developments in interpersonal violence. In the narrow setting of death investigation, our results will provide an evidence-based approach to understanding the injury patterns in sharp force homicide.     

Fatal suicidal injury of a radiocephalic arteriovenous fistula

A 59-year-old man was found dead in his living room. His body was covered with blood, but the only injury found was a 31-mm-long, transverse incision on the radial surface of the left forearm. Autopsy revealed that the injured vessel was an enlarged cephalic vein from a radiocephalic arteriovenous fistula (RC-AVF) that had been created 23 years before for hemodialysis. Cephalic vein injury is usually not fatal, but circumstantial evidence, autopsy, and histological findings suggested that hemorrhagic shock and death occurred within a short time after the self-inflicted incised wound. This may be explained by the blood flow rate in the RC-AVF, which can reach 12 ml/s; this is 25 times higher than the normal cephalic vein blood flow.     

146例体表损伤类型与致伤物分析

目的 探讨致伤物推断的法医学鉴定及其鉴定意见的证据价值.方法 收集1998-2007年间皖南医学院司法鉴定中心受理的致伤物推断案件146例,通过人体体表损伤特征的分析,推断致伤物.并通过推断致伤物与实际致伤物的比较,分析致伤物推断的准确性. 结果根据锐器伤推断致伤物的准确性要比根据钝器伤推断致伤物的准确性高.结论 致伤物推断结果尚存在一定的不确定性,必须结合其他证据,才能作为定案的依据.     

Multiple Self‐Inflicted Stab Wounds to Neck,Chest and Abdomen as a Unique Manner of Suicide

Abstract: This is a case report of a 30‐year‐old man found dead in his flat lying on the floor with multiple stab wounds over the body, surrounded by an extensive volume of blood. Examination of the scene of death showed a secure flat, locked from inside. A blood‐stained knife was present close to the body and two unstained notes left on the sofa at the locus. A small plastic bag containing white powder (which following toxicological examinations appeared to be cocaine) and an almost full bottle of beer were present on a table. Autopsy revealed more than 40 stab wounds to neck, chest, and abdomen arranged in isolated groups within which the wounds showed similar directions and had a transverse orientation. Together with hesitation marks located on the neck and wrists these characteristics allowed to interpret this case as a suicide.     

Alteration of the Death Scene After Self‐stabbing: A Case of Sharp Force Suicide Disguised by the Victim as a Homicide?

This paper reports a case of a 72‐year‐old woman who was found dead in her bedroom with a 4 cm vertical stab wound in the abdomen. A bloodstained knife was found in the top drawer of her bedside table. The clothes worn by the victim showed no damage. A bloodstained vest and a sweater with frontal incisions were found far from the victim, in the bathroom and in the bedroom respectively. Several bloodstains were found in every room of the apartment. The evidence found during the forensic examination and, in particular, the Bloodstain Pattern Analysis, led the investigators to determine the manner of death, being consistent with a suicide with a long‐lasting physical activity after self‐stabbing. This report describes an unusual case of “disguised suicide,” in which the victim tried to cover‐up the suicide by changing her clothes and concealing the weapon, in the last minutes of her life.     

Fatal Injuries of Law Enforcement/Correctional Officers Attacked with Sharp‐Edged Weapons,

According to the National Law Enforcement Memorial Fund, there were 117 law enforcement fatalities in the United States in 2015. Assaults with sharp‐edged weapons have resulted in a total of over 400 fatalities in the United States. The goal of the current research was to examine sharp‐edged weapon assaults against law enforcement and correctional agents that resulted in a fatal outcome. A total of twelve autopsy reports were reviewed from across the United States. Four cases involved law enforcement officers, seven involved correctional officers, and one was an off‐duty border officer. The male‐to‐female ratio was 11:1. A total of 70.2% of the wounds analyzed were stab wounds (n = 85), and 29.8% of the wounds were slash wounds (n = 36). Based on this review, the neck, shoulder, and chest regions were the most vulnerable to single fatal stab/slash wounds. Multiple stab/slash wounds often resulted in exsanguination. The use of body armor was only noted in one case.     

Hesitation Wounds and Sharp Force Injuries in Forensic Pathology and Psychiatry: Multidisciplinary Review of the Literature and Study of Two Cases

The aim of this paper was to showcase the significant diagnostic value of hesitation wounds in terms of forensic, psychiatric, and medicolegal interest. A number of studies were reviewed to update and summarize the relevant literature on the incidence, distribution, character, and function of hesitation wounds as well as the sociodemographic variables and psychopathology of the inducers. This study also investigates their importance as a forensic criterion in the distinction between suicide and homicide as well as a psychiatric diagnostic tool in suicide prevention. In addition, the paper reports two new cases. Results conclude that there is equal incidence, but different distribution of hesitation wounds between genders. Furthermore, the low dispersion of hesitation wounds contrasts with the high dispersion of defense wounds. The inducers' psychopathology lies principally in Axis I disorders. Finally, there is a comprehensive analysis of non‐suicidal self‐injury and the role of self‐wounding in suicide prevention.     

90例行人撞击伤案例分析

目的 探讨行人交通事故和致伤车辆类型的关系,总结其规律.方法 回顾90例行人交通事故案例,分析致伤车辆、损伤部位、损伤特点、严重程度之间的关系. 结果 不同类型致伤车辆所致的撞击伤好发部位取决于受撞击时人体的姿势和车头突出部位的高度,其损伤特点与作用力大小、方向和接触面光滑程度相关. 结论 通过对行人撞击伤的损伤部位、损伤特点、严重程度的分析,可以推断致伤车辆类型.     

Characteristics of Bone Injuries Resulting from Knife Wounds Incised with Different Forces

The aim of this research was to experimentally determine the characteristics of incised bone wounds, which are commonly found in defense injuries. A specially constructed pivoting arm device was used to inflict wounds with controlled forces and direction. Five knives were selected to inflict the wounds on porcine forelimbs. Eight incised wounds were made per knife per force. A larger knife and a greater force caused longer and wider bone wounds. Comparisons of individual knives at the two forces produced varying results in the bone wounds. A correlation was seen between the force and the length (r = 0.69), width (r = 0.63), and depth (r = 0.57) of bone wounds. Serrated‐edge and nonserrated knives can be distinguished from the appearance of the wound. The outcomes may be applicable in forensic investigations to ascertain the forces associated with incised wounds and identify the specific knife used.     

Breaking point? An analysis of fatal stab wounds to the torso in Ireland between 2011 and 2018, examining the extent of rib fractures

This study examines the pattern of rib injuries occurring in cases of fatal torso stab wounds in Ireland between 2011 and 2018. It has been suggested by previous studies that rib fractures are not commonly sustained in stab wounds to the torso. We wanted to ascertain whether this was the case, as our data suggested that rib fractures were frequent, and where a rib is fractured there is a higher chance of organ injury and death, making this an important area of study. One hundred and forty seven cases of fatal stab wounds from an eight-year period were retrospectively reviewed. Fatal stab wounds to other body areas, were excluded; leaving a total of 104 cases with stab wounds to the torso. We found that 69.2% of cases had rib injuries, a figure significantly higher than previously reported. Our data suggests that stab wounds to the torso often fracture ribs, putting the underlying organs at increased risk of injury and perhaps contributing to fatality. The amount of force needed to cause a rib fracture can be difficult to quantify and indeed from the high percentage of rib fractures sustained in our data it appears that the ribs may be fractured regardless of the amount of force used; this is borne out by the finding that self-inflicted injuries also caused rib fractures. Our study shows that other factors, such as anatomical positioning and wound depth may have a greater bearing than force in terms of whether a rib fracture is sustained.     

Macroscopic and microscopic analysis of knife stab wounds on fleshed and clothed ribs

Stab wounds upon bone are analyzed to interpret the weapon used and the physical context in which the attack occurred. The literature demonstrates that most research conducted pertaining to wound patterns has been carried out on defleshed and unclothed bone samples, not adequately replicating actual circumstances. For this research, six half pig torsos (Sus scrofa), fleshed (including muscle, fat, epidermis, and dermis layers) and clothed, were stabbed using three knife types, applying both straight and downward thrusts. Analysis conducted macroscopically and through a scanning electron microscope with an environmental secondary electron detector revealed a general lack of consistency in wound pattern and associated secondary effects. Consequently, it was not possible to establish wound pattern per knife type as suggested in previous research or relate it to stab motion. Advantage of microscopic analysis was evident in recognizing wound traits and observation of trace evidence not visible macroscopically.     

Death certification of "suicide by cop"

Death certification of "suicide by cop" is controversial among some medical examiners and coroners. We present five such deaths that were certified as suicides and discuss the medico-legal issues involved with these certifications. To certify such a death as a suicide, certain criteria should be met. Suicide by cop is a circumstance that involves competing intentional acts that may result in dichotomous determinations of the manner of death. Despite the absence of direct self-infliction, there is overwhelming evidence that these five individuals intended to end their own lives. Their use of an unusual method to accomplish this goal may inappropriately result in a reflexive certification of homicide. All of the decedents possessed weapons or a facsimile of a weapon. We present five instances of suicide by cop and contend that these types of deaths are best certified as suicides.     

Homicide by unusual‐edged weapons: Forensic considerations of two cases

Homicide by stab wound is common worldwide. However, the use of unusual edged weapons is rarely reported in the forensic literature. Here, we report two cases of homicide involving a Japanese sword, or katana, and a sickle. Both of these weapons can create either stab or incised wounds with some particularities. In our cases, characteristics of the external wounds, internal injuries, and the depth of penetration raised the possibility of an unusual weapon. Meticulous forensic examination of these injuries (morphological characteristics, depth of penetration, trajectories, and cut marks in the bone) may allow the forensic expert to determine the type of weapon used.     

SEM and Stereomicroscopic Analysis of Cut Marks in Fresh and Burned Bone

This study documents the prevalence of cut mark characteristics in fresh and burned domestic pig ribs. Stab wounds from single edge serrated and smooth‐edged knives were inflicted in the vertebral and sternal regions of each fresh rib. Each rack of ribs was then divided into vertebral and sternal units. Vertebral units were defleshed and their associated cut marks were examined using a stereomicroscope. Sternal units were burned in an outdoor fire pit and examined with the addition of a scanning electron microscope (SEM). Linear cuts, V‐shaped cross‐sections, mounding, hinge fractures, and wastage were all observed on burned ribs. There was an overall decrease in the prevalence of all features (up to a 40% decrease), regardless of knife type, in burned ribs. Striations within cut marks were not observed in either fresh or burned ribs. Oblique faulting and bone lifts could only be observed using the SEM. Mounding and wastage were obliterated during the burning process. Therefore, cut marks in burned bone should ideally be examined for their characteristics utilizing an SEM.     

Obesity,Body Mass Index,and Homicide

The body mass indexes (BMIs) of 100 randomly selected homicide cases from the files of Forensic Science SA were compared to the Australian and South Australian populations. There were 70 males and 30 females (M:F = 2.3:1; age range 18–84 years; mean 42.3 years). There was a substantially lower proportion of obese individuals in the homicide population compared to the general Australian and South Australian populations (19% [vs.] 27.9% and 30%, respectively). A second group of 144 randomly selected autopsy cases where the BMI was ≥40 kg/m² was analyzed. There were 77 males and 67 females (M:F = 1.2:1; age range 23–78 years; mean 46.7 years). The majority of deaths were natural (N = 108), with no homicides. A negative association between obesity and homicide has, therefore, been demonstrated. Reasons for the lower numbers of obese/morbidly obese individuals among homicide victims are unclear, but may include physical protection afforded by fat padding from sharp force injuries, and relative sociodemographic isolation.