Criminal Justice: An Examination of Physical Evidence and its Role

This report provides an overview of physical evidence in criminal justice, emphasizing its crucial role in litigation. It categorizes physical evidence into fingerprints (including latent, patent, and plastic types), impression evidence (tire marks), trace evidence (fibers, hairs), and documentary evidence. The report references Rule 401 of the Federal Rule of Evidence, which defines the admissibility of evidence, and discusses the significance of each type of evidence at a crime scene, such as the Turn-a-round lounge. It also highlights the importance of forensic science labs, including latent fingerprint sections, trace evidence sections, forensic garages, and questioned documents labs, in the analysis and interpretation of physical evidence. The report references the work of several experts in the field to support its conclusions.

Criminal Justice - Evidence
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Physical Evidence
Physical evidences are the any kind of evidence that can be physically obtained in the scene
of crime. These evidences are also called the real or material evidence. The physical evidence
tends to play a vital role in the formation of the litigation charges and can be produced in case
proceedings as a support in forming a conclusive decision for a case. The chief types of
physical evidences that are collected from a scene of crime involves fingerprints, footprints,
marks of tire or biological evidences like the DNA samples that are collected from the body
parts of fluids as they also form a subcategory of the physical evidence. The Rule 401 of the
Federal Rule of Evidence discusses the concept of evidence (Carroll 2009). This section
states that evidences are facts the presence of which can make a conclusive decision in
generating a decisive result of a case.
Types of Physical evidence in the crime scene
There are different types of evidences that can be collected from the turn-a-round lounge
depending on the nature of crime.
Fingerprints: the fingerprint in most of the cases are visible without the aid of any devise in
case they are not visible to the bare eyes than they are called latent fingerprints. The latent
fingerprints have been collected from the crime scene of the Turn-a-round lounge. These
types of evidences are chiefly generated from the sweat or oil coming from the skin. Latent
fingerprints are visible from the other lighting sources that are used. It is notable that the
hands and feet don’t have any oil glands as a result latent fingerprints of hands and legs can
be considered to be coming from other sources. It is also to be noted that the cold hands tend
to leave less strong finger prints in comparison to warm hands. In case someone in engaged
in fighting activities the chances of generating body heat is higher so this types of evidence
can be considered to be of importance in this case. The presence of the fingerprints or
footprints of a person in a place can be considered as significant evidential proof of the
person being present at the scene of crime. There are different types of fingerprints that can
be collected like patent fingerprint which are prints of other material on body parts which is
in turn printed in some location of the crime scene. The plastic fingerprints which are prints
of hands and legs that are on a soft surface like liquid or semi solid substance (Bhargava et al.
2009). Bloody footprints are impressions that are formed from source of blood which ends up
making marks in some other substance. This evidence has also been available in the Turn-a-
round lounge’s crime scene in terms of blood stained footprints which were present in the
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exit of the place. It is also notable in this case that there were three footprints that have left
the location of crime in turn-a-round lounge. These types of physical evidence are considered
as conclusive in nature in a case.
Impression evidence: impression evidences involve marks that are formed when there is a
significant level of contact between two objects that leaves evidential impression. The
patterns that were formed by the tyre of the car of Sam and Michelle in the mud parking of
the lounge can be considered under this type of evidence. The imprints that are formed in the
mud because of the pressure of the tyre can provide classification information like type of
vehicle, pattern of the vehicle and the possible direction of the motion of the car (Bhargava et
al. 2009). The ‘Tire book’ which provides information regarding around 5000 different tyre
prints can provide evidential proof regarding the identity of the tyre as well as the possible
track that is taken by the vehicle.
Trace evidence: the searching of the trace evidence is one of the most important aspects of
the forensic investigation. Trace evidences can cause to develop conclusive evidences that
can help in deciding the case. The trace evidences involve substances that are likely to be
overlooked unless microscopic investigation is done. This can involve cloth fibres, hairs, dirt
material etc. The Locard’s Exchange principal states that a person cannot be in interaction
with a situation without collecting any evidence from it or leaving any evidence of his or her
presence in that place (Tedeschi 2013). Trace evidence involves traces on the body of the
victim, small fabric of clothing, trace evidences from foot wares, footprints on floor, traces of
metal, weapons in this case the knife and biological trace evidences.
Documentary evidence: the documentary evidences involve papers and writings. In this
murder case threatening letters were claimed to have been written by Joe the victim. They
were found in the house of one of the suspects that is Michelle.
Sections of forensic science labs
Latent fingerprint section: the latent fingerprint section of the forensic lab uses several
chemical and non chemical procedures to determine the fingerprints. The fingerprint section
of the forensic laboratory also involves activities like using of the international fingerprint
database to recognise the person whose fingerprint has been collected (Tedeschi 2013).
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Trace evidence section: the trace evidence section takes into consideration traces of
evidences that are microscopic in size. This section is highly dependent on microscopy, FTIR
microscopes, electron microscopes etc (Robertson Vignaux & Berger 2016).
Forensic Garage: the tire impressions and the possible structure and model of the car can be
examined in the forensic garage section. This section deals with all information regarding the
detail of cars. They are chiefly responsible for the processing of evidence regarding the
impression that is made by the wheels of the car in this case (Saferstein 2013). These are also
called the examination area for vehicles involved in a crime scene.
Questioned documents lab: This is the section of forensic lab that conducts investigation
regarding papers and inks that has been collected as evidences in the investigation of a case.
This section also takes into consideration the verification of the authenticity of the document
that has been presented as evidence in solving a case (Siegel & Saukko 2012). In this murder
the threatening letters of the victim that is Joe has been found in the house of one of the
suspects that is Michelle during the investigation. Michelle claimed that the letters were
written by Joe however the documents lab can confirm the authenticity of the document.
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Reference List
Bhargava, R., Perlman, R. S., Fernandez, D. C., Levin, I. W., & Bartick, E. G. (2009). Non-
invasive detection of superimposed latent fingerprints and inter-ridge trace evidence
by infrared spectroscopic imaging. Analytical and bioanalytical chemistry, 394(8),
2069-2075.
Carroll, J.L., (2009). Proportionality in discovery: A cautionary tale. Campbell L. Rev., 32,
p.455.
Robertson, B., Vignaux, G. A., & Berger, C. E. (2016). Interpreting evidence: evaluating
forensic science in the courtroom. John Wiley & Sons.
Saferstein, R. (2013). Forensic Science. Pearson/Prentice Hall.
Siegel, J. A., & Saukko, P. J. (2012). Encyclopedia of forensic sciences. Academic Press.
Tedeschi, J. T. (Ed.). (2013). Impression management theory and social psychological
research. Academic Press.
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