According to Ronald (1990, there are basically four types of evidence; the first being anecdotal which is very weak and involves describing one specific instance or instances of the same type or structure. The weakness of this type of evidence is that, it cannot be relied on in proving a general statement and alone, it is also insufficient in disapproving a general statement. The second type is testimonial evidence which is moderately strong as well as supportive. It is characterized by a reference to a trustworthy authority from well-established sources. This is considered to strengthen an argument, although one has to say why a particular person’s comment should especially be considered. However, an assumption should not be made that credentials that are respectable alone should always be accepted without being questioned. The third type of evidence is statistical evidence and it makes use of empirical analysis. Results of scientific experiments are used for investigations and the source of such results must be reported; whenever they are used to structure an argument. Multiple sources are encouraged with this type because different sources tend to conflict. The fourth type of evidence is analogical evidence which offers supportive evidence and is fairly strong. It involves explanatory modeling of a specific phenomenon, through comparison with another phenomenon that is already understood. This type helps one to connect things but lacks a hard proof for any person who would be resisting a particular view.
There are various types of information that can be derived from different specimens collected such as the kind of tools that were used, as well as the extent of assault caused. If evidence involves blood stains, it should be collected on a gauze pad and dried at room temperature. The stain should be frozen within the shortest time possible and taken to the laboratory before 48 hours are over. If evidence involves seminal stains, which are usually found on blankets, clothing and sheets, the stain should be allowed to dry. It should then be wrapped in a paper and packaged but caution should be observed not to pack the specimen in a plastic bag. For sexual assault, there is a specific collection kit that directly collects the evidence from victims. Instructions on the kit have to be strictly followed to maximize benefits from the evidence. The victim also has to be examined by a qualified physician. The garment needs to be labeled such as panties and then packaged separately. “A possible race of a person can easily be identified through collection of evidence such as human hair. Usually glasses also serve as evidence as they are normally broken in cases of burglaries or headlights; after run-and-hit incidences” (Ronald, 1999 p. 105).
Collected evidence is examined by a qualified specialist and the mode of examination depends on the nature of the specimen. Every piece of evidence should be analyzed several times throughout the actual investigation by following all the required steps. These include development of photos as quickly as possible; looking at the pictures to see if there could be anything one cannot explain. This is done using high quality machines like video editors documenting all the analysis (Tim, 2007).
Tim (2007) argues that some possible contamination issues with the collection of evidence include erased writing, damaging as well as destroying potential fingerprints and confusion during labeling. Research has revealed that, in all cases, the primary precaution should focus on preventing addition of fingerprints to the collected evidence or destruction of the already existing ones. Any unnecessary contact must be avoided even when the person collecting the specimen uses gloves and handkerchiefs.
References
- Ronald, L. (1999): Criminological theories: introduction and evaluation: Taylors & Francis pp. 102-108
- Tim, N. (2007): criminology: William Publishing pp. 413-420