Scene Examination in Cases of Sharp Force Trauma
Written by Peter Vanezis   

AN EXCERPT FROM
Pathology of Sharp Force Trauma

 

This article appeared in the May-June 2021 issue of Evidence Technology Magazine.
You can view that full issue here.

A SCENE IN WHICH THE DECEASED IS DISCOVERED and has sustained sharp force wounds is usually associated with significant blood on and around the body and requires careful assessment of the quantity and the distribution of the blood together with other scene findings to assist in attempting to reconstruct the events leading to death. It is therefore vital that the scene and/or scenes be identified and protected to allow uninterrupted examination by the investigating team and prevent or minimize contamination by uninvited persons.

As part of the multidisciplinary forensic team, the pathologist will work alongside colleagues to assess the body and its environment as well as assisting in the collection of evidence. Reconstructing the circumstances in which a person has died when they are discovered at a scene requires a number of important initial questions which need to be addressed. They include, whether or not the deceased died at the location in which they were found, and how (the manner) the deceased came to their death—in other words, is it a case of homicide, suicide, or accident?

In a number of instances, although the police are very anxious for some initial guidance by the pathologist to assist them with their investigation, it is not always possible to give any clear answers in a specific way regarding the manner of death or the type of weapon used. I have experienced cases where, because there had been a large amount of blood and sometimes clothing and other material covering the wound sites, it had made difficult any differentiation between different types of wounds such as stab or firearm injuries, or even masked the wound completely. Since the scene is not the place for the pathologist to carry out a detailed examination, for obvious reasons of contamination, the safest approach is to keep one’s own counsel until the post-mortem examination in the mortuary has been carried out.

Scenes are so varied that one can only categorize them in very broad terms. The examination of each type of scene frequently requires a different approach, with the attendance of appropriate forensic expertise. When assessing a scene, the senior investigator will decide on the approach and the various types of experts that might be required. This will depend on the location, type of incident, number of deceased, health and safety aspects, urgency of examination, and climatic conditions.

Location of a Body
The location may be in a building or enclosed within a structure, such as a residence or workplace. It is essential to understand the connection, if any, between the location and the deceased, i.e. if the location is the deceased’s residence.

Domestic disputes are a common cause of fatal stabbings; and in some series stabbing occurs, most commonly, in the victim’s own home. Rogde et al. (2000), from a series of 141 homicides from two Scandinavian capitals—Oslo and Copenhagen—found that 78% of all females were killed in their own home, while this was the case for 49% of males. This is hardly surprising as many of the victims are known to their assailants; and knives in a household, particularly from the kitchen drawer, are close at hand to be used as weapons. Among the victims killed in their own home, 51% of the females and 35% of the males shared this home with the offender (most often their spouse) (Figure 1). By contrast, 21% of males were killed outdoors compared to only 6% of females.


Figure 1. The deceased was found stabbed in the lounge by her husband.

In a case example, the male victim was found collapsed outside the entrance to an address which was close to where he lived. There was a trail of blood from his flat to where he collapsed. Resuscitation attempts were carried out, including a clamshell thoracotomy, but the deceased died from a stab wound to the neck and had also suffered a number of other injuries (Figure 2).


Figure 2. The victim (a) is on the ground at the foot of the steps of the front door (b) which show substantial amounts of blood. A clamshell thoracotomy has been carried out and medical equipment as well as other items from medical intervention have been left on and around the deceased.

An outdoor scene may be either an urban or countryside environment and in a number of situations involves some degree of concealment, particularly in homicide cases where there has been an attempt to dispose of the body. Occasionally a body is disposed of by burial and there may well be the need to locate the deceased.

The author was part of a team which investigated the case of a fully clothed body of a woman that was discovered in a shallow grave next to a lime tree (Figure 3). She had been missing for five years. Her identification was based on medical records including the use of facial superimposition. The length of internment in the grave was calculated from the lime tree root lengths and their rings growing through her. It is believed that this was one of the first cases where this technique was employed. The botanist was accurate to within one season from the five years from when she had been missing. Since then, there have been a number of publications in the forensic literature which have demonstrated the usefulness of examination of tree roots and other associated plant growth as a means of estimating the length of internment (Quatrehomme et al., 1997; Margiotta et al., 2015).


Figure 3a. Back garden of house where deceased has been buried.


Figure 3b. Partly dug grave showing human remains.


Figure 3c. Fully clothed, skeletonized remains, with some adipocere present in the legs.


Figure 3d. Tears in blouse from knife.


Figure 3e. Root growing through blouse.

The cause of her death was established by close examination of her clothing and skeletal remains. Examination of her lace blouse, particularly on the inner aspect, clearly demonstrated two tears, although more were suspected, that appeared to have been caused by a knife. Examination of her rib cage confirmed a fracture to the fourth left rib anteriorly, fifth rib below showing complete severance, and a small cut on the inner aspect of the sixth rib. All were in line and were typical of a thrust of a sharp implement such as a knife into the chest (Figures 4 and 5). From the damage seen to the fourth rib, it was reasonable to assume that the knife used had entered up to the hilt with the assailant’s hand also making contact against the chest, delivering the blow as if by a hard punch. The skeletonized chest was devoid of soft tissues but this did not deter the court from making the correct assumption that vital organs would have been seriously injured (Vanezis et al. 1978).


Figure 4. (a) Left anterior rib cage showing the location of damage caused by stabbing to the fourth, fifth, and sixth ribs. Detail of the ribs show (b) rib 4 with is fractured. (c) Rib 5 is severed and (d) the sixth rib is cut on the inner aspect (arrow). All are indicative of a forceful overarm stabbing motion.


Figure 5. Stab wound to lower right side of body of the sternum (arrow).

A further case seen by the author which illustrates the importance of a thorough scene examination is that involving a missing 14-year-old schoolgirl who had been abducted and murdered by her stepfather (Vanezis 1996b). He had been sexually abusing her since she was an 8-year-old child. He was convicted of her murder before her body was found. Whilst in prison, and from conversations with other prisoners, it emerged that she did not die in a car crusher, as he had originally asserted, but he had killed her by other means and had deposited her body in a disused Victorian cemetery in North London. Most of her remains were eventually found, partially covered by dense vegetation after they had been scattered by predators to different parts of the periphery of the cemetery (Figures 6, 7, and 8). Identification was confirmed by her mother from her clothing found separately but nearby (cardigan, skirt, and shoe) as well as a ring, watch, and necklace. Assessment of the remains by an anatomist and dentist found her age to be consistent with that of the missing girl. In addition, examination of clothing and skeletal remains by a forensic scientist and myself revealed findings demonstrating that she had been stabbed, which included a diagonal clean cut on a portion of one of the left ribs. On her cardigan there were five tears typical of having been caused by a knife, as well as a number caused by animal teeth. The knife tears were to the front left part of the cardigan. A further six tears were seen on the left sleeve, indicating that she had tried to defend herself.


Figure 6a. Mandible found separately from other scattered remains.


Figure 6b. Ring found nearby.


Figure 7a. Garments and other objects worn.


Figure 7b. Close up of tears on left side of cardigan.


Figure 8. (a) Partial skeleton recovered and (b) Section of a rib identified with a diagonal cut caused by a sharp implement. On the shaft there can also be seen marks most probably caused by animals.

A body found in, or near, water begs the question, in cases of sharp force and other types of injury, whether or not the individual had been killed and deposited into a river, sea, or other body of water. The injuries need to be assessed as to whether they are antemortem or post-mortem. If they are ante-mortem were they responsible for causing death or did the deceased, despite suffering injuries before death, die from drowning or some other cause associated with water. Such cases may well provide serious challenges for the investigators.

A number of issues need to be resolved such as where the deceased entered the water in relation to where they were found. The use of diatomaceous examination may provide some insight into this aspect of the investigation, although results should be treated with caution (Coelho et al. 2016). They emphasize the importance of the creation of a diatom database at different regions and at different seasons to assist the investigator with identifying potential points of entry into water.

A number of complex suicides have been reported using more than one method of self-injury including, very rarely, self-stabbing followed by drowning. The first complex suicide involving multiple stab wounds followed by drowning was reported by Kaliszan et al. 2013. The victim, a young man, was seen walking into the sea partially submerged. He had at some stage stabbed himself in the chest and abdomen a number of times before disappearing under the water. A post-mortem examination revealed emphysema aquosum which is typical of drowning. He left some of his personal belongings on the beach. Suicide was clearly determined on the basis of the circumstantial evidence prior to death, where he was found, and the distribution of the wounds on his trunk. Peyron et al. (2018) report a case of a man found in a river with 18 stab wounds, which presented a serious challenge in assessing whether the deceased had died from his wounds or from drowning and whether or not they were self-inflicted or homicidal. He had been stabbed in the chest and was found to have a haemothorax and lung injuries. However, the post-mortem and histological examination revealed that the death was consistent with a death caused by drowning. They were not certain of the manner of death, although a police investigation concluded that the death was a suicide.

In the case of a deceased found by the seashore—or indeed close to any body of water, such as a riverbank—the question will arise as to whether the person died at the site of discovery or had been previously in water. This is not always an easy question to answer and will depend very much on the investigation of the circumstances and post-mortem findings.

Such a question arose when a 60-year-old man was found partly covered by seaweed by some rocks close to a harbor wall. Initially it was not known whether he had entered the water from one of the ships just outside the confines of the harbor or fallen over from the harbor wall. The post-mortem examination revealed a stab wound to his left upper arm and an incised wound to the back of his head and to the palm of his right hand. There were superficial friction marks, indicative of contact with stones from the harbor wall near where he had been found. Following local enquiries, it was established that a man, later identified as the deceased, had been involved in a knife fight with two men. During the fight, he had lost his balance, fallen over the harbor wall and drowned.

In addition to some of the locations discussed above, there are many other types of locations such as the street, commonly seen in cases of gang violence, or in other public places including bars, night clubs, and elsewhere.

Position of the Body
The position of the body may be of assistance in many cases to resolve both the manner of death (whether homicide accident or suicide) and help reconstruct the scenario and ascertain the locus where wounding had occurred and whether or not the deceased had died in the same area where injured, or had moved elsewhere, either when still alive by the victim moving themselves after injury, or being moved after death. It is crucial for the pathologist to document the position of body and ascertain whether it had been moved prior to his/her attendance at the scene and reasons for doing so. There are a number of legitimate reasons why a body may be moved from its initial position:

  • movement by someone e.g. relative to check for signs of life
  • for resuscitation purposes
  • to collect evidence which may otherwise be lost or become contaminated
  • to secure/make the scene safe.

Blood Distribution
The handling of the scene, the blood distribution and the collection of trace evidence are, on the whole, tasks that are addressed by forensic scientists and police personnel, although with respect to blood distribution there are some areas of shared expertise between the biologist and the pathologist. In one case seen by the author, the blood on the blade of the knife was wiped from the blade onto a shirt which had been covering a radiator, giving an impression of the width of the blade and sharpness of its tip (Figure 9).


Figure 9. Blood staining on shirt caused by wiping the blade used in stabbing.

The appearance of blood needs to be assessed in relation to the position of the body and in particular to any wounds that are found. The pattern of distribution of such blood stains may indicate whether they were produced during life or after death. Care must be taken to assess the distribution and quantity of blood with regard to whether or not movement of the body has taken place prior to carrying out scene examination, for example for resuscitation. Such movement may cause large quantities of blood to flow from major stab wounds. The blood in these cases originates from within the body cavity and, particularly with chest wounds, large quantities may spill out on to the floor on turning the body over.

Examination of the bloodstain patterns at the scene gives an insight into the actions and activities of victim and assailant and may be of particular value in assessing the direction of travel of blood spots, their velocity on impact, and distance travelled (Figure 10). Forensic scientists, experienced in blood distribution patterns, will use their experience, together with experimental testing and published work, to interpret different patterns in order to estimate site of attack and number of impacts. The size and orientation of stains, from spots to splashes, is indicative of the type and location of the attack. By the very nature of many sharp weapons, most cases of homicidal sharp force injury require close contact between the perpetrator and the victim. As such, important trace evidence (hairs, fibers, fluids) that might potentially link a suspect to the crime might be present on the victim or at the scene. If the attacker sustains injuries during the attack, the suspect’s blood and/or hair may also be present at the scene. With certain sharp force homicides, a sexual assault may have preceded or coincided with the sharp force attack. An examination of the scene may be helpful in identifying seminal fluid or other trace evidence.


Figure 10. Arterial blood spurts from the left common carotid artery seen on the door, opposite the left side of the face and neck. Observe the extensive pooling of blood from his wounds and the footprint marks from blood surrounding the deceased's head.

Tissue damage to a body, which may be of a very extensive nature, can be produced by pets with no other access to food when acting as predators and locked in a house with their owner (Rossi et al. 1994). At first sight, such injuries may resemble incised or puncture wounds.


About the Author
Peter Vanezis OBE is Professor Emeritus of Forensic Medical Sciences at the William Harvey Research Institute, Queen Mary University of London. He began his career in forensic medicine at the London Hospital Medical College in 1974 in the department headed by Professor James Cameron. He became Reader and Head of the Forensic Department at the Charing Cross and Westminster Medical School in 1990, following which he was appointed Regius Professor of Forensic Medicine and Science in 1993 at the University of Glasgow. He was awarded the OBE in 2000 for leading the British Forensic team in the investigation of mass graves in Kosovo. After establishing a forensic pathology unit at the Forensic Science Service in 2003, he was appointed to the new chair of Forensic Medical Sciences at Queen Mary University of London where he pursued academic activities until his retirement in 2018. He continues his interest in forensic medical education and research through his Academy of Forensic Medical Sciences.


References

Coelho, S., P. Ramos, C. Ribeiro, J. Marques, A. Santos. 2016. Contribution to the determination of the place of death by drowning - A study of diatoms' biodiversity in Douro River estuary. J Forensic Leg Med. 1(41):58–64.

Kaliszan, M., K. Karnecki, E. Tomczak, T. Gos, Z. Jankowski. 2013. Complex suicide by self-stabbing with subsequent drowning in the sea. J Forensic Sci. 58:1370–1373.

Margiotta, G., G. Bacaro, E. Carnevali, S. Severini, M. Bacci, M. Gabbrielli. 2015. Forensic botany as a useful tool in the crime scene: Report of a case. J Forensic Leg Med. 34:24–28.

Peyron, P. A., T. Casper, O. Mathieu, Y. Musizzano, E. Baccino. 2018. Complex suicide by self-stabbing and drowning: a case report and a review of literature. J Forensic Sci. 63:598–601.

Quatrehomme, G., A. Lacoste, P. Bailet, G. Gr.vin, A. Ollier. 1997. Contribution of microscopic plant anatomy to postmortem bone dating. J Forensic Sci. 42:140–143.

Rogde S., H. P. Hougen, K. Poulsen. 2000. Homicide by sharp force in two Scandinavian Capitals. Forensic Sci Int. 109:135–145.

Rossi, M.L., A. W. Shahrom, R. C. Chapman, P. Vanezis. 1994. Post-mortem injuries by indoor pets. Am J For Med and Path. 15:105–109.

Vanezis, P. 1996b. Scene location and associated problems, Chapter 5, p. 77, in Suspicious Death Scene Investigation, Eds. P. Vanezis and A. Busuttil. Arnold: London.

Vanezis, P., B. G. Sims, J. Grant. 1978. Medical and scientific investigations of an exhumation in unhallowed ground. Med Sci Law. 18:209–221.

 
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