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 where 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 her self 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.
No comments:
Post a Comment