Trace Evidence at Crime Scene Student’s Name Institutional Affiliation

Trace evidence are substances established in very small amounts at the point of crime that can be analyzed and investigated to come up with viable information about the subject under investigation. Such substances may include hair, fiber, glass, glass, metal, paper, paint or botanical sources such as soil, pollen or leaves. Presence of these traces is as a result of the culprits unconsciously coming into contact with the surface (Fish & Braswell, 2011). How long such traces remain at the crime scene depends on the persistence of the substance in terms of its size and shape, amount deposited, actions between deposition and revival, scenery of environment and the amount of time passed. Irregular services tend to collect the evidence more readily than smooth surfaces.

Paint can be in term of liquid, fragments, or smears. This usually identified in terms of color, type, texture, layers structure and composition. When paint dries it forms a layer that is thin and hard. It is made up of several constituents that include carriers, pigments, modifiers, extenders and binders. Carriers are the substance that becomes a solid when evaporation takes place usually an organic liquid. Pigment is the substance that gives the paint its color (Fish & Braswell, 2011). It is worth noting that blue and green pigment is usually organic compounds whereas red, yellow and white color pigment is usually inorganic. Modifiers are substances that controls paint properties e.g. its flexibility and damage resistance. Extenders on the other hand increase paints volume and improves its coverage. Last are the binders which its main aim is to stabilize the paint and enhancing it.

The best ways to analyze paints is either mechanical, physical, and chemical forms. In the mechanical analysis paints flakes are matched in an attempt to find out whether it resembles a jigsaw puzzle. The chemical analysis tries to determine the actual composition of the sample by the use of different chromatographically techniques. On other hand, physical analysis deals with the color, texture, thickness, appearance and the pattern of occurrence by use of microscope (Fletcher, 2006).

Soil is usually collected at the crime scene by professionals in criminology investigations. The soil sample is collected within a 100-yard radius at the crime spots. In addition if soil is found on the shoes this is usually left and the shoe taken to the crime lab for investigation. While taking these samples it is important to use dogs since it may not be visible. More so the investigators should be very careful and be well dressed to avoid the distortion of the samples. The soil samples should be of high standard in that it should not be contaminated and should be within the standard radius of the within which the crime occurred (Fletcher, 2006). All these taken into consideration all will be in order and at most the intended results will be retrieved from the soil samples collected. It is worth noting that different areas have different chemical make up during sample collection.

During the soil examination the soil is dried under the standard lab conditions to determine physical and chemical characteristics. Through microscopic examination physical characteristic are determined to reveal presence of plants and animals or any artificial debris. Soil color is also determined (Genge, 2002). Chemical characteristic is examined to come up with pH and different elements and compounds present in it. It is compared with different soil samples from different point of the scene occurrences. Soil texture is also examined and its luster.

During the investigation scientist usually make their investigation to determine the location in which the crime took place or the path in which the drugs were transported through. It also helps understand what happened at the crime scene and identify who is responsible for the crime (Genge, 2002).

References

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Fish, J. T., Miller, L. S., & Braswell, M. (2011). Crime scene investigation. Amsterdam: Anderson Pub. Books.
Fletcher, C. (2006). Every contact leaves a trace: Crime scene experts talk about their work from discovery through verdict. New York: St. Martin's Press.
Genge, N. (2002). The forensic casebook: The science of crime scene investigation. New York: Ballantine Books.
Current Issues in Criminal Justice - 2

Next, you will consider how corrections personnel should behave and what procedures they should follow in relation to inmates.
In this assignment, you will write a standard of behavior for corrections personnel at a prison to follow when interacting with inmates. • Include 10 elements in your standard. • Describe the ethical reasoning behind each standard. • Give an example of corresponding unethical behavior that would break each element of the standard.

Assignment should be two to three page(s) in length.

Bloodstain pattern analysis can be used to determine where the victim and suspect were located, as well the directionality of the impact. • Complete the “Blood Spatter Evidence” activity that is located on the CD-ROM accompanying your textbook. • Explain the terms “area of convergence” and “area of origin” and explain what each term reveals to an investigator. • How is the area of convergence determined? • How is the area of origin determined?

• An in-depth submission that should be free of spelling and grammar errors. • An essay 1-2 pages in length.
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