Collecting The
Evidence
The collection of the various forms
of forensic evidence, by the Scene of Crimes Officers (SOCO’s), from the crime
scenes of each of Aileen Wuornos’s seven victims was essential as it
contributed to the case being built against the perpetrator as well as enabling
various further lines of enquiry to be identified that ultimately led to the
apprehension of the serial killer responsible for the brutal killings.
The Scenes of Crimes Officers
(SOCO’s) ensured that all of the physical, biological and chemical evidence
that was collected from the scenes of each of the seven victims was done so in
a manner that ensured that the evidence could not be made inadmissible when it
was presented to the Court. In the case
of Aileen Wuornos the forensic evidence that was located at the various crime
scenes had to be identified, photographed and collected using the appropriate technique
for that specific piece of evidence. For
example when the vehicle belonging to Richard Mallory was examined by the Scene
of Crimes Officers (SOCO’s) the discovery of two plastic tumbler glasses was
identified and it was ultimately the responsibility of the Scene of Crimes
Officers (SOCO’s) to use their expert knowledge in order to identify the
appropriate packaging that should be used.
As the two plastic tumbler glasses potentially had saliva and
fingerprints belonging to the perpetrator on them the preservation of the
evidence was essential and they would have been placed into an airtight package
such as a sealed paper bag which would prevent any distortion or loss of
evidence. The Scene of Crimes Officers
(SOCO’s) will have applied their personal protective equipment (PPE) prior to entering
the scene of the crime in order to prevent any contamination or destruction of
any forensic evidence. If the Scene of
Crimes Officers (SOCO’s) were to enter the scene of a crime without applying
their personal protective equipment (PPE) and collect forensic evidence, for
analysis at the scene or at the forensic laboratory, the evidence will be
deemed inadmissible in Court as the correct procedures and practices in
relation to the collection of evidence have not been followed. The two plastic tumbler glasses were a key
piece of evidence that will, although not found in any available documentation,
have been presented to the court if the identification of any fingerprints or
saliva were matched to that of Aileen Wuornos.
Once the Scene of Crimes Officers
(SOCO’s), in the case of Aileen Wuornos, had identified the forensic evidence
that they thought relevant to the criminal investigation they would have
photographed the evidence prior to its collection so that when the case was
presented to the Court the photographs would have been used to prove their
location and presence at the crime scene, this is particularly important as the
validity of certain pieces of forensic evidence will have been questioned by
the defence as a method of trying to prevent their client being deemed guilty
of the charges they have been charged with.
When the Scene of Crimes Officers (SOCO’s) were collecting the relevant
forensic evidence from the various crime scenes they will have ensured that the
process of transferring the evidence from the scene to a suitable receptacle
was done so using the appropriate technique.
For example when the Scene of Crimes Officers (SOCO’s) identified a
blonde hair in the vehicle that was found to belong to David Spears they will
have carried out the correct procedures and practices in relation to the
collection of evidence, the hair will have been photographed prior to its
transferal to an envelope that can be sealed using the peel-back adhesive strip
on the lip of the envelope and then subsequently tape is placed on the outside
of the packaging. The adhesive tape will
enable the forensic scientist, who is responsible for analysing the evidence at
the scientific laboratory, to identify whether the forensic evidence has been
tampered with during its transportation from the scene of the crime to the
scientific laboratory.
In order for the forensic evidence to
be collected from the crime scene using the appropriate technique the Scene of
Crimes Officers (SOCO’s) must ensure that they use the appropriate technique,
in regards to the hair located in the vehicle of David Spears the use of
sterile tweezers would have been used to transfer the hair from the steering
wheel to the envelope. When collecting
the various forms of evidence to prevent the evidence being destroyed or
contaminated which will ultimately make it inadmissible in Court the correct
procedures and practices should be followed in relation to the collection of
evidence.
Following the discovery of the
vehicle that was found to belong to Peter Siems the Scene of Crimes Officers
(SOCO’s) located numerous suspected bloody prints and bloodstains. The Scene of Crimes Officers (SOCO’s) will
have used their knowledge regarding the collection of biological evidence in
order to collect the sample suspected to be blood, a sample of the suspected
blood will subsequently be transported back to the forensic laboratory. The suspected blood will have been
photographed prior to its collection and subsequently swabbed used a sterile
swab. The tube which contains the
suspected blood sample will prevent the sample from deteriorating to a point
where it cannot be used.
The preservation of forensic
evidence, particularly biological evidence that is sensitive to the environment
that it is kept in, is essential to any form of criminal investigation as
without the correct procedures the evidence may become unusable or the validity
of the evidence can be questioned if it is presented to the Court. The use of the Kastle-Meyer (KM) presumptive
test which contains phenolphthalein, a reagent, a dye which is colourless will
be used at the forensic science laboratory in order to confirm that the sample
is in fact blood. The Kastle- Meyer (KM) presumptive test can also be carried
out at the scene which can in turn save resources and money. When this reagent is combined with hydrogen
peroxide the bloods haemoglobin in a suspected sample reacts by producing the
colour pink. Kastle-Meyer (KM) involves
the use of ethanol, Kastle-Meyer (KM) reagent and hydrogen peroxide applied to
a suspected sample of blood on filter paper or cotton swab. A colour change to pink caused by the various
chemical reactions will indicate if blood is present on the suspected sample. The correct analysis of the blood sample is
essential to the criminal investigation for if the suspected blood sample is
confirmed to be blood it can then sent for further analysis were by a DNA
profile can be produced and potentially a match to a suspect made. In the case of Aileen Wuornos, although not
found in any available documentation, the suspected blood found in the vehicle
of Peter Siems would have been used to identify whether the sample of blood
obtained from the suspect matched the blood found in the vehicle.
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