Trace Evidence.edited
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Trace Evidence
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Discussion Post
Explaining to the CSI partner in training the methods of finding trace evidence,
cautions on not losing or destroying it, and collection methods.
Trace evidence connects perpetrators, victims, and crime scenes through tiny physical fragments
moving throughout a crime
(Buzzini & Curran, 2020)
. Trace evidence can be gathered through the
use of the following techniques; Optical search: This is a thorough examination of the crime
scene to look for any traces of evidence that might be clear to see using the naked eye
(Buzzini &
Curran, 2020)
. Another technique deployed is utilizing different illumination: locating trace
evidence that might otherwise go undetected in well-lit areas is possible. Laser beams, UV lights,
and infrared light are alternative luminaires that can help locate trace evidence at a crime scene
(Buzzini & Curran, 2020)
.
Biochemical tests: Certain sorts of trace evidence can be found using
chemical tests. For instance, fluorescent dyes, which react with the metal in hemoglobin to make
the blood light in the dark, can be used to check for blood.
It is essential to undertake the following precautions
when gathering trace evidence to
prevent losing or altering it. Wear gloves when gathering trace evidence to prevent damage and
avoid depositing personal DNA or fingerprints on the material
(Buzzini & Curran, 2020)
.
The
instruments used to gather trace evidence must be clean and devoid of traces from earlier
investigations
(Buzzini & Curran, 2020)
.
Each item of proof must be identified with its area, date,
and moment of collection and the identity of the individual who gathered it; this help to prevent
cross-contamination.
Other trace evidence can be collected through the following methods; Hair: Use forceps
to delicately pluck hairs, being cautious not to injure the base or shaft. Each hair needs to be
contained in its paper bag. Fibers: Fabrics can be delicately removed with forceps or taped to a
3
surface to be collected. Each fiber needs to be contained in its paper wrapper.
Swabs may gather
minute amounts of evidence, including blood and other bodily fluids
(Athar, 2020)
. They help
obtain DNA samples as well.
Relating the components of human hair that are considered class characteristics
The aspect of human hair, described as a class attribute, refers to characteristics similar to
a group of people. The elements of human hair class attributes include Cuticle Scale Sequence:
The cuticle comprises lobes and is the hair shaft's outer part. These plates can have different
patterns that vary from person to person, but the coronal, spinous, and imbricate varieties are the
most prevalent
(Athar, 2020)
.
Cortex Layout: The cortex, the hair shaft's middle part, is where the
pigmentation that gives hair its color is found
(Athar, 2020)
. Each person has a unique cortical
anatomy, including thickness and form.
Pigmentation: How color is distributed within the hair
shaft can also serve as a class feature
(Athar, 2020)
.
Using these classifications of hair evidence,
forensics experts can eliminate some possible suspects and establish a case against the offender.
Explaining how the Locard Principle plays a significant part in the transfer of trace
evidence and the importance of identifying and collecting it for the investigation.
The Locard's Exchange Principle is the central concept in forensic science because it describes
how trace evidence can move between individuals, things, or surroundings.
According to this
theory, there is a substance exchange every time two substances come into direct contact
(Athar,
2020)
. The transmitted material may include physical evidence like hair, fibers, DNA, and other
micro or macroscale components. Since there is an exchange of materials in every crime scene,
as explained in Locard’s Principle, finding and gathering trace evidence is crucial because it can
offer insightful details about the incident and assist investigators in compiling evidence against
the perpetrator
(Athar, 2020)
.
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References
Athar, M. (2020). Trace evidence: A versatile key in forensic investigation.
International Journal of
Forensic Sciences
,
5
(2). https://doi.org/10.23880/ijfsc-16000193
Buzzini, P., & Curran, J. M. (2020). Interpreting trace evidence.
Handbook of Trace Evidence Analysis
,
421–454. https://doi.org/10.1002/9781119373438.ch7
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Compound
1
2
Et
onal Academy of Science. All Rights Reserved.
Mass Fe
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Enter the answer that belongs in the green box.
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A docs.google.com
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Some account servi
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Arial
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BIUA
E = E = EE E - E E X
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.. 6 I 7 O 8 1 IC
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(sodium
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Suspect #4: Ben Linus
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