When the criminal investigation team
gather evidence at the crime scene, there are procedures for the collection and
preservation of this evidence. This would be how the investigation team
physically collect the evidence and what they use to do this, and also what
they use to preserve the evidence for example; the right packaging and tagging
of that evidence.
It is important that the investigation
team use the right equipment when collecting evidence. This is so they do not
damage the evidence or get the best sample of that evidence that they possibly
can. An example of this could be using a swab to collect a sample of blood; the
investigation team wouldn't use tweezers to collect this because they wouldn't get the best sample from using that piece of equipment. Different pieces of
equipment are used to collect the different types of evidence and different
packaging will be used for the different types of evidence. The coroner for a
deceased would be a way of evidence is collected. The coroner is called out
when an individual has died, if this individual is involved in a homicide, this
body will be examined.
Packaging of this evidence is important
in order to prevent damaging that evidence. This would be the material of the
packaging and the size of the packaging. The material pf the packaging plays an
important role because if a piece of evidence is not put into the right
packaging it could damage or ruin that evidence. An example of this would be if
a weapon that had blood on it was put into a plastic container. The box could
build up with residue which could ruin the evidence. It’s also important that
the evidence is put in a package size suitable for that evidence. For example
putting a blood swab in a container and in a sealed plastic bag would be more
suitable than putting that evidence in a plastic box.
After the evidence has been packaged
correctly, it is a procedure to tag or label that evidence. This label or tag
includes important information like the case reference that the evidence
belongs to, the date, and identification number, the names of the individuals
who have handled that piece of evidence and details of that evidence. This is
an important procedure because if this evidence was lost or misplaced, the
information on the label should tell that individual enough information to
return that evidence to its correct case. Also if the evidence has been
tampered with, the names of the individuals who have handled that piece of
evidence is on the tag.
Once the evidence has been correctly
collected, packaged and tagged, it is then analysed using suitable techniques.
Different types of evidence will be analysed using techniques. A presumptive
technique most commonly used to analyse blood sample to see whether they are
blood would be the Kastle Meyer test. This technique includes adding 3 liquid
components; ethanol, Kastle meyer and hydrogen peroxide, onto the sample. A
colour change to pink will indicate to the team that the sample is positive for
blood. This sample would then be taken back to the labs for examination and
further analysis.
Chemical evidence would be analysed
using a different technique to biological evidence because they are different
types of evidence. A commonly used technique used to analyse drugs which is
chemical evidence would be identifying what drug is at the crime scene. Marquis
Reagent is a liquid component added to the sample which performs a colour
change test which then allows us to identify what drug it is due to that colour
change. This technique is only a presumptive test and would be sent back to the
labs where further analysis could be performed such as spectroscopy and
chromatography.
Other pieces of evidence that may not
have been specifically collected from the crime scene but still have
involvement in the case would also be analysed. This could be witness
statements or surveillance videos. These
would be types of evidence that are produced by technical aids such as CCTV or
listening devices. These would be used to identify individuals, look at
locations and also the time when those pieces of evidence were produced.
Witness statements are important pieces of evidence in investigations because
they might be able to identify things that the investigation team may not know
because they did not see the crime take place. These would be analysed as to
whether they are valuable evidence in the investigation because they can supply
detailed information but also may be biased and opinionated statements.
The biological evidence of this case
being the fingerprints would have been collected using specific techniques and
equipment. The technique to collect these were dusting which involves dusting
fine powders to objects or areas intending for the particles of the powder to
adhere to residues left by the hands and fingers of individuals. This evidence
would then be analysed by forensics in order to try and match that fingerprint
to a possible suspect. These fingerprints were preserved in sealed envelopes
which were then given to the forensic team.
Witness statements were valuable pieces
of evidence in this investigation. This is because of the lack of physical
pieces of evidence that these witness statements could give the investigation
team any information and details. These witness statements included reported
viewings of an individual carrying a young child who matched Madeleine’s
description. This witness statement revealed the ‘Tanner sighting’. Witness
statements also given by residents of the holiday destination came forward with
information which then made the investigation team question another resident of
that area on Madeleine disappearance. This shows that an analysis of the
witness statements were carried out which lead to further lines of enquires.
Although there were many witness statements given, there were none that saw
Madeleine wondering off by herself or a kidnapper abducting Madeleine from the
apartment. There were no surveillance videos that gave the investigation team
any evidence or leads in the case. If surveillance videos gave evidence, this
could have been used to identify any individuals present in the videos and also
the location.
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