Scene of crime and Scene of Death
Every scene of crime is a scene of death but vice versa is not always true.
Scene of Death
This can be defined as a place from where a dead bod is found. Just because a body is lying there it does not mean that the death has occurred there. It may be the place of disposal. It may also be the place where the death has occurred but injury/injuries may have been inflicted somewhere else.
A scene of a death can turn out to be a scene of crime after the visit of the doctor. If the death is obviously due to a crime e.g. death due to multiple fire arm injuries the police will treat it as a scene of crime from the outset. But in rare cases, police may want the doctor to visit the scene and exclude criminal activities before they declare it not a ‘scene of crime’.
Scene of crime
It can be defined as a place where a crime has taken place. It does not need to be a death. Even a place where rape has taken place is regarded as a ‘crime scene’. Usually doctors are required only in crimes scenes involving deaths. Other ‘crime scene’ investigations are done by relevant experts such as forensic scientists, finger print specialists, botanists etc. and not by doctors. In a crime scene the doctor’s role is limited to the examination of the dead body. The recovery of forensic samples, which may include, bullets, cartridge cases, blood, fiber, foot and fingerprints etc. is the responsibility of the relevant forensic scientist.
Visting a scene of crime
Visiting a scene of crime of a death is part of the post-mortem examination. The evidence gathered by such examination is used in the following manner.
1. Informing the police whether a crime has taken place. For instance, if the doctor finds suspicious marks on the neck with petechial haemorrhage on the tarsal plates in a unsuspected sudden death. They should inform the police that it is a suspicious death. If the doctor finds that the pool of blood in which the deceased is lying originated from his mouth and he has all the stigmata of chronic liver diseses. The doctor should inform the police that it is not suspicious as blood appears to have originated from the ruptured oesophageal varices.
2. Estimation of time since death. The most reliable of methods of estimation of time since death, which is body cooling method, should be done at the scene of death.
3. Exmaination of blood stain pattern might give a clue to time of survival, activities of the deceased at the time and immediately after the injuries were inflicted.
4. Interpretation of the injuries may be easy if the doctor understands that there are many agents at the scene which could potentially produce injuries on the deceased. Sometimes the origin of complex injuries which is impossible to be interpreted at the autopsy room may be clear when the scene is visited e.g. a man with complex cuts on the face may have fallen on broken glass.
5. interpretation of the post mortem injuries. For instance only a scene visit will reveal the presence of carrion eaters, which may have caused bizarre postmortem injuries on the body.
How to visit a scene of crime
The doctor does not need a magisterial order to visit scenes of crime. A police request, may be written or verbal, is more than enough.
In some occasions, the doctor visits the scene of crime even after the body has been removed and some times even after the autopsy. This is usually to facilitate the interpretation of injuries. For instance only a scene visit may reveal an unsual projection on the ground which had caused a depressed fracture on the occipital bone mimicking an assault with a hammer
Who should visit the scene?
The overall responsibility of managing scene of crimes is with the police. The crime scene manger is a police officer who will coordinate the visits of the individual expert. If it has to be investigated scientifically it should be visited by all the experts at the same time as a team. Before it is visited the police, crime scene manager, should organize a meeting of police and experts to plan the various aspects of its examination.
As soon as it is decided that the scene of death is a scene of crime the police shoud
1. Cordon off and seal the area
2. Don’t allow no- investigators (public/media) to come in
3. Inform magistrate/ inquirer, JMO, and forensic investigators without delay
4. Make the scene safe e.g. burned down house, site of bomb explostion
The member of the team may include
1. Scene of crime officer (SOCO)
2. Magistrate/ISD
3. JMO
4. Forensic scientists
5. Police investigators (finger print officers, kennels etc)
Scene of Crime officers (SOCO)
They are specially trained police officers, who are responsible of recovering of forensic evidence. They do not have a role in interpretating them. Their duties include:
- Protecting the crime scene to avoid evidence being disturbed
- Searching an area for footwear marks and examining for fingerprints
- Taking photographs of accidents and injuries
- Taking samples from people for DNA testing
- Examining for and collecting trace evidence such as hair, fibres and blood
- They are responsible for identifying bodies through DNA or fingerprint testing.
- Preparing statements of evidence
- Attending court with the exhibits collected in the course of an enquiry
- The SOCOs do not investigate crimes or analyse evidence themselves.
- They are not considered as experts by the court of law
Magistrate
Although they do not have any investigative or prosecuting role the laws says that they should visit the scene and record all the findings and form opinions about the causation of injuris. According to the code of criminal procedure act number 15 of 1979
1. They should immediately visit the scene where body lies.
2. Make an inquiry and draw up a report of apparent cause of death describing the injuries, marks, objects and circumstances.
3. Give an opinion about the manner in which the injuries and marks occur.
JMO
It need not be a consultant JMO to attend a scene of crime. Even a MO-medico-legal should be able to attend and do the necessary investigations.
Role of the JMO
1. Examine the body in relation to the locus.
2. Note the type and location of visible injuries on the body.
3. Sketch, describe and photograph the body/bodies in relation to the scene
4. Look for evidence of post injury movement.
5. Collect evidence for time of death, time of injury, time between injury and death.
6. In general leave the clothing, ligatures and other items best leave intact with the body to examine at the mortuary.
7. Any item that is unlikely to survive the transportation process should be photographed removed and collected at the scene (Eg Knife).
8. In suspected sexual assaults it is ideal to collect swabs at the scene itself.
9. Hands and feet should be bagged in paper prior to putting the body into body bag.
10. Supervise and instruct the transportation of the body.
If not visited by the Forensic Pathologist
1. Transportation artifacts may be created
a. New injuries may occur or existing injuries can get altered during transit.
b. Clothing will be disarranged
c. Blood stains will form on parts of clothes originally free from them.
d. Fresh tears in clothes may be produced from rough handling.
e. Existing rigor mortis may be broken down at least partially
2. Valuable evidence can get lost
3. Valuable evidence on event reconstruction might missed
e.g. Blood stains
4. Can affect the estimating of time since death
Advantages of visit of a Forensic Pathologist
1. Gets evidence on time of death, time of injury and time between injury and death.
2. Finding evidence for possible movement of the victim after injury (volitional activity).
3. Finding evidence for possible movement of the body.
4. Get clues to the cause and manner of death
5. Interpretation of injuries.
6. Safe transportation of the body
Practical aspects
TO DO
1. Respond to the calls for scene visit immediately
2. Hands in pocket
3. Mouth shut
4. Eyes wide open
5. Ears receptive
6. Separate living from dead
7. Observe thoroughly
8. Take notes, describe, sketches, measurements, photographs with land marks
9. In a case of mass disaster number bodies and parts before documenting.
10. Observe to estimate the time since death
11. Observe evidence of movement of the body
NOT TO DO
1. Approach without the permission from crime scene manager
2. Tamper with the scene unnecessarily
3. Contaminate the scene
4. Give premature opinion
5. Autopsy at the scene
6. Interview the mass media
Forensic Scientists
Forensic scientists who should attend a scene of death depend on the scene of crime. It is the responsibility of the police to call upon the relevant expert to attend the scene e.g. if it is a firearm death the ballistic expert should be called.
It should be remembered that the doctors are no supposed to recover forensic evidence from the scene of crime. It is the job of the relevant forensic scientist or the SOCO. However, recovery of forensic evidence from bodies (both dead and live in case of clinical cases) is the responsibility of the doctor.
a. Bomb and ballistic experts
1. The investigation conducted at the scene of an explosion or bombing plays a vital role in uncovering the truth about the incident.
2. Collect, study, and analyse evidence related to ammunition and firearms and bombs
3. The evidence recovered can be critical in identifying, charging, and ultimately convicting suspected criminals.
b. Forensic entomologists
Collect entomological evidence
Useful in timing and event reconstruction.
c. Blood stain pattern analysts
1. Blood stain pattern analysis applies scientific knowledge in biology, chemistry, mathematics and physics to solve practical problems.
2. Can produce strong, solid evidence, making it an effective tool for investigators.
Trace evidence
Trace evidence is a very small piece of evidence left at a crime scene or bodies of victim or assailant that may be used to identify or link a suspect to a crime. The evidence can be collected at the scene, autopsy room or at the clinical examination room.
The following types of evidence, among others, may be analyzed:
- Stains and secretions
- Hairs and Fibers
- Paints (automotive and architectural)
- Explosives
- Glass
- Headlamp Filaments
- Footwear and Tire Impressions
- Physical Matches
- Arson Debris
- Acids/Bases
- Miscellaneous Unknowns
Although trace evidence on its own is often not enough to make a case, it could very well corroborate other evidence or even prompt a confession which could help to solve the case
Concept of trace evidence (Locard’s exchange principle)
Whenever there is contact between two objects (whether either are a living thing or not), there is a transfer of material between them. It is therefore the responsibility of forensic experts to find that transfer evidence, however difficult it may be to locate. This is called Locard’s exchange principle; Proposed in 1910 by Dr. Edmond Locard.
Must include permanent notes about;
1. Date (and time, when appropriate) of the collection,
2. Name of person or persons collecting the evidence,
3. Descriptive listing of item or items collected,
4. Unique identifier for each item collected such as an item number and case number
5. Location of each item (notes, sketches, measurements, photographs, or a combination of these).
Collection
The method used for collection is generally dependent type of evidence and from where or what sort of object it is being collected. The most important thing to remember is to avoid contamination.
1. Shaking (Hair, broken buttons from clothing etc)
2. Brushing (foreign hair on hairy body parts)
3. Taping (small hair, weed, paint particles adhered on body)
4. Swabbing (Stains)
5. Hand picking (bullets)
6. Clipping (Finger nails)
7. Vacuuming (A vacuum cleaner equipped with a filter trap is used to recover trace evidence from an item or area. The filter and its contents should be immediately packaged to avoid sample loss. This method should be used after other collection techniques as it is indiscriminate and may result in the collection of a large amount of extraneous material)
8. In some cases, such as oil or grease, a solvent extraction can be used to collect the evidence for analysis.
9. Storage, security and chain of custody should be maintained.
Priyanjith Perera
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