University of South Wales
Referral Coursework 2012-2013
1A. The procedures and protocol of the collection, preservation and packaging of all aspects of evidence from various crimes that maybe encountered by a criminalist.
The search for physical evidence at a crime scene must be done thoroughly and followed by the protocol. How the criminalist will decide to execute the crime-scene investigation depends on the size and the locale of the area, as well as on the actions of the suspect(s) and victim(s) at the scene. It must be considered that physical evidence can be anything, from a massive object to a microscopic trace, however, some evidence are clearly visible but others need to be examined in the laboratory in order to be detected. Physical evidence must be processed in a way so as to prevent any change from happening between the time that was collected on the crime scene and the time it is received by the laboratory. When collecting physical evidence from a scene, any criminalist must be aware of the fact that recovery of one type of evidence can destroy another. Once a piece of physical evidence has been recovered it is of vital importance to be properly packaged, labelled and stored as soon as possible after the recovery. Furthermore, in order to avoid cross-contamination or any damage through contact all items must be packaged in separate appropriate containers. All containers must be completely sealed in order to avoid losing a valuable evidential item or for avoiding cross-contamination between the samples. There are several types of physical evidence, for that reason there are different packaging containers. A criminalist in order to be well-prepared must have a large amount of tools and different packaging containers when examining a crime-scene. Small items or trace evidence such as hair, glass and fibres can be packaged at an unbreakable plastic pill bottle with pressure lids or they can be wrapped in pre-folded paper (this is known as “druggist fold”). Manila envelopes, screw cap glass vials or cardboard pillboxes are the most common used packaging containers at crime scenes. However, some items of physical evidence such as blood-stained materials and clothing require other forms of containers; blood-stained materials have to be packaged in a wrapping paper, manila envelope or a paper bag in order to avoid the growth of mold. When items of clothing have to be packaged they need to be air-dried first and then placed into paper bags so as to ensure a constant circulation of air through them. Furthermore, when physical evidence is recovered from a crime-scene, adequate control samples must be collected as well. The control samples are taken for two reasons. Control samples are needed in order to enable evidentially important information to be detected from the background and to help in the comparisons between known control samples and samples that are taken from the crime-scene.
1B. Physical Evidence at crime scenes. Definition, description and recognition of a range of aspects of physical evidence and appreciation of their evidentiary value with respect to advancing the investigation.
Physical evidence includes any and all objects that have the ability to demonstrate that a crime has been committed or can provide a link between the crime and the victim or the crime and the perpetrator. There are a lot of types of physical evidence such as blood, semen and saliva, documents, drugs, fibres, fingerprints, hair, soil and minerals and impressions. It’s one of them consists of a category; all blood, semen, or saliva present in a form so as to suggest a relation to the crime or the people involved in it. Blood and semen can be found dried onto fabrics or other items and saliva residues can be left onto a cigarette butt. Fibres, natural or synthetic whose transfer can be useful can establish a relationship between items or persons. Drugs, any substance confiscated in violation of laws. Animal or human...
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