Sydnee Brain 193024
UNIT 23: Forensic Evidence, Collection and Analysis
GATHERING AND PRESERVING FORENSIC EVIDENCE
UNDERSTAND HOW TO GATHER FORENSIC EVIDENCE, THE INTEGRITY
TO FORENSIC INVESTIGATION AND THE IMPORTANCE OF HEALTH AND
SAFETY
Forensics includes scientific tests and techniques carried out and used in
connection of finding out the who, what, when, where and how of a crime.
There are four key stages in an investigation, the scene of the crime,
forensic science analysis, interpretation of analysis, and forensics science
and the law and criminal justice system.
Documentation
There are many steps, procedures and precautions taken in a forensic
investigation, these include, authorised personnel and specialists,
documentation methods, risk assessments and collection and preservation
of evidence. All evidence, photos, facts and theories are discussed and
considered by the investigating team to identify significant witnesses,
suspects, persons of interest and motives, as well as any linked offences
and/or crimes and any areas where intelligence needs to be developed to
fill any knowledge gaps.
In a forensic investigation, it is very important that documentation
methods are used to keep a record of data throughout the whole
investigation. In many cases, poor scene documentation could lead to
inadmissible evidence in court, and evidence that has not been noted or
recorded could consequently allow a guilty party to get away with a
crime.
An example of an important document is the cordon log, this keeps track
of everyone who enters and leaves the scene, this is important because it
shows exactly who, when and why people were at the scene. It also helps
in cases where SSU, fire fighters, paramedics and other emergency
services are present as they could naturally contaminate the scene by
attending to help a victim or asses the situation, having a record of them
there would rule them out as a person of interest. Another documentation
method includes sketches and photographs, these are the most effective
, Sydnee Brain 193024
UNIT 23: Forensic Evidence, Collection and Analysis
ways to represent a crime scene by the investigating officer, they supply
significant pieces and details with exact measurements of the site and
evidence where the crime occurred. Examination forms are also a form of
documentation used by forensic scientists as a way of recording details
about their examinations of evidence submitted to their laboratory,
without this, there would be no record or note of the evidence being
examined.
Evidence labels are another way of documenting, as they are used to
label exhibits, this makes it easy for items to be identified at a later date,
they also show who and when the last person touched the item.
Authorised personnel
Cordons are typically one of the first people called to the scene and will
carry out specific measurements to stop any media or other unauthorised
personnel from contaminating and/or damaging the crime scene and any
evidence, or taking away crucial trace evidence on their shoes, hands,
clothes etc. Measurements to restrict outside access can include, taping
off the scene, placing barricades at points of entry and even having police
officers standing guard. After the scene is secure the cordon then fills out
a log sheet to keep record of every person, including witnesses,
paramedics and other authorised personnel that enters and leaves the
crime scene and the time they did so. This type of measurement helps
limit the amount of people who must be examined when stray fingerprints
and shoeprints are found.
Depending on the nature of a crime, the cordon will also contact a
scientific support unit to attend the scene. The SSU use modern, cutting
edge technology which can help examine forensic evidence collected from
a crime scene, fatality or incident to help piece together what happened.
This particular unit includes personnel to specialise in efficient crime scene
examination, central submission of evidence, lab examination, fingerprints
and DNA, and photographic evidence.
One unit of the SSU is forensic expertise and CSI, these specialists carry
out forensic examinations in the laboratory such as, searching items from
the suspects and victims of a crime for blood, semen, saliva and cellular
material. The involves using a range of techniques and equipment.
