Criminal
Investigation In Practice
It is
essential when attending a crime scene that the scene is secured using crime
scene tape which will prevent the scene from contamination, any destruction of
evidence occurring or the disappearance of forensic evidence. The crime scene tape should surround the
scene of the crime which will ensure that the Scenes of Crime Officer (SOCO)
will analyse, collect and package any forensic evidence that is relevant to the
crime that has been committed.
The role of
securing the scene will be that of the First Attending Officer (FAO) as he/she
will be the first person present at the scene and will therefore be required to
ensure that any forensic evidence is protected from contamination, destruction
or disappearance. The First Attending
Officer (FAO) will also have the role and responsibility of carrying out the
Initial Scene Assessment which will detail if any victims or suspects have
received any medical attention and if so whether any forensic evidence has been
moved in the process. The Initial Scene
Assessment will also detail the information relating to any suspects that have
been questioned and instructed to stay at the scene of the crime. The First Attending Officer (FAO) will have
the role and responsibility of preventing any unauthorised personnel from
entering the crime scene such as; the press, friends, family or the actual
perpetrator himself/herself. It will be
down to the judgment of the First Attending Officer (FAO) to determine the
appropriate method for securing the scene of the crime, for example the scene
of the crime may be an outdoors environment which may require the First
Attending Officer (FAO) to erect a tent to protect the scene itself, any
forensic evidence, and any victims that may be present at the scene.
In the case
of Aileen Wuornos all of her victims, except Peter Siems, were located in
heavily wooded secluded area. Therefore
the First Attending Officer (FAO), in the case of Aileen
Wuornos, would have had to ensure that the appropriate cordoning off of the
scene was carried out using crime scene tape.
The First Attending Officer (FAO) will have had to protect the victims
from any further damage from the environmentby erecting a tent to ensure that
the bodies were protected from the hot weather conditions. The priority for the First Attending Officer
(FAO) is to identify whether or not a criminal offence has been committed which
in turn determines whether or not other resources, such as Scenes of Crime
Officers (FAO), will need to be requested to attend the scene. In the case were the First Attending Officer
(FAO) comes to the conclusion that a crime has been committed an entry log will
be used to detail the title of the authorised personnel entering and exiting
the scene, the time at which he/she did so and the date of entry/exit to the
crime scene. The entry log is an
essential document that must be used at every crime scene, regardless of the
type of crime, as it will be referred to in court if the case does in fact go
to court.
Upon arrival
at the scene of the crime, the Scenes of Crime Officer (SOCO)and Investigating
Officers/Detectives will be informed by the First Attending Officer (FAO) of
the forensic evidence that is visible to him/her, the details regarding the
crime that has been reported, any eyewitnesses and details of the information
that the eyewitness/s has provided as this may prove insightful to the criminal
investigation. Following the relay of
information from the First Attending Officer (FAO) the Scenes of Crime Officer
(SOCO) will be aware of what relevant forensic evidence needs to be collected
that will assist in the criminal investigation.
In the case
of Aileen Wuornos the victims had all sustained multiple gunshot wounds,
although the rate of decomposition had in turn prevented the medical examiner
from being able to determine the cause of death at the scene of the crime for
some of the victims, however if the cause of death was clear the Scenes of
Crime Officer (SOCO) may have been able to search for any shell casings. It is also the responsibility of the Scenes
of Crime Officer (SOCO) to determine whether the forensic evidence that he/she
wants to collect is relevant to the criminal investigation as if it is not it
will waste valuable resources and delay the progress of the criminal
investigation. In order for the Scenes
of Crime Officer (SOCO) to be aware of what forensic evidence is valuable to
the criminal investigation he/she will need to be informed by the First
Attending Officer (FAO) as to the nature of the crime that has taken place, for
example if the criminal offence that has taken place is suspected to be related
to drugs the Scenes of Crime Officer (SOCO) can be aware that substances that
they find at the scene of the crime that he/she suspects to be drugs should
analyse them at the scene, if possible using spot tests, or collect and package
the substance appropriately for transportation to the forensic laboratory for
further analysis. It is vital that the
information from the First Attending Officer (FAO) is relayed as it gives clear
insight into the nature of the criminal offence and subsequently what further
lines of enquiry need to take place.
In the case
of Aileen Wuornos, what would turn out to be Peter Siems car was found on
Wednesday 4th July 1990 at 9.44pm by Trooper Rickey. However, the Police failed to carry out a
fingerprint check in relation to the bloody fingerprints that were located in
the vehicle.
Prior to
entering a crime scene, the Scenes of Crime Officer/s (SOCO’s) will put on the
relevant Personal Protective Equipment (PPE) in order to prevent any
contamination of the crime scene as well as any evidence present that is
collected.
An initial
crime scene assessment would be carried out which would include sketches and
photographs of the crime scene along with the weather condition at the scene
noted.
It is
essential that prior to the Scenes of Crime Officer (SOCO) entering the crime
scene that a Common Approach Path is set out by in order to ensure that all of
the authorised personnel who enter and exit the scene of the crime follow one
path and do not deviate from the path which may cause contamination or
destruction of forensic evidence which may have proven to be key to the
criminal investigation. The Common
Approach Path begins at the point at which the crime scene begins to the focal
point of the crime scene and consists of either metal stepping plates or
cardboard markers.
Every crime
scene would have an evidence log which would record all the evidence collected
from the crime scene using each pieces given unique identification number. The evidence log is a written record of the ‘chain
of custody’ of all exhibits which can be referred to in order to identify who
has come into contact with that exhibit and handled it following the correct
procedures to avoid contamination. It
would provide the court with the documentation of the order in which each
exhibit was found, collected, analysed, by whom and the evidence recorded.
How evidence
is collected and preserved depends on the type of evidence at the crime
scene. A crime scene could contain
biological evidence, such as; bodily fluids, fingerprints, blood, soil, pollen
etc – chemical evidence, such as; medicine/s, drugs, poisons, gunshot residue
(GSR), paint, accelerants and physical evidence, such as; tyre marks,
vehicle/s, footwear marks, video footage (CCTV), weapon/s, etc.
Collecting
blood, biological evidence, at a crime scene would be done by the Scenes of
Crime Officer (SOCO) using a swab that is rolled in the suspected blood which
would then be sealed in a tube using crime scene tape on which would be written
the time of discovery/collection, what it is suspected to be, location of
discovery, the Scenes of Crime Officer (SOCO’s) identification number, exhibit
reference and property reference number.
It would then be placed in an evidence bag that would be sealed and a
permanent marker used to write the aforementioned information which is done to
prevent the evidence being tampered with.
When
collecting a suspected murder weapon, physical evidence, such as; a knife the
Scenes of Crime Officer (SOCO) having photographed the weapon would place the
knife in a suitable evidence tube and seal it in order to preserve any evidence
on it such as blood and fingerprints. It
is then placed in an evidence bag which is sealed and then crime scene tape
applied. The time of discovery/collection,
what it is suspected to be, location of discovery, the Scenes of Crime Officer
(SOCO’s) number, exhibit reference and property reference number would be
completed on the evidence bags label.
In the case
of Aileen Wuornos a blonde hair was
located on the steering wheel of the truck that belonged to David Spears on the
20th May 1990 as well as an opened packet of Trojan condoms which
had been discovered on the floor of the truck.
The hair would be classed as biological evidence if the hair root bulb
was still attached and trace evidence if it was not while the condom packet
would be classed as physical evidence. They would be collected following the correct
procedures for evidence collection in order to avoid contamination of the
evidence whilst recording it in the evidence log.
At the forensic
laboratory the forensic scientist, wearing the appropriate Personal Protective
Equipment (PPE), will initially carry out the Kastle-Meyer (KM) test which is a
presumptive test on the sample suspected of being blood. This involves the use of ethanol, Kastle-Meyer
(KM) reagent and hydrogen peroxide are applied to the suspected sample of blood
on a cotton swab. A colour change to
pink caused by the various chemical reactions will indicate if blood is present
on the suspected sample and if so the sample will be sent for further analysis by
a forensic serologist in order to provide a DNA profile which can be used to
identify a match to a suspect.
The physical evidence,
knife, that is suspected of contained both blood and fingerprint evidence would
be analysed in two ways initially. The
Kastle-Meyer (KM) test would be carried out to determine whether blood is
present on the knife and the sample further analysed by a forensic serologist
in order to determine whether the blood is that of the victim or the victim and
the perpetrator of the crime.
A method that can be used for developing latent fingerprints on
the knife is Superglue Fuming
(Cyanoacrylate). This method of
fingerprint development works as the traces of fatty acids, proteins and amino
acids that are present in latent fingerprints along with the moisture in the air
react when the superglue is heated to produce a gas which adheres to the ridges
of a fingerprint and can be seen as white.
This method requires a chamber that has the appropriate extraction
system fitted. The item is then placed in the chamber and a few drops of
superglue are placed in an open container on top of a heater, the chamber is
then sealed and the heater inside the chamber is turned on. Once the superglue reaches boiling point it
turns into a gaseous cyanoacrylate, the exposure and natural humidity which is
contained in the atmosphere trigger the reaction. This process can take a long time dependant
on many factors; the size of the chamber, what the concentration of gaseous
cyanoacrylate is in the air and the humidity of the air etc. As the fingerprint is clearly visible
following this process it can be photographed immediately prior to any further
enhancements. The whole process must be
carefully monitored as if the item is left for too long the latent fingerprints
will overdevelop meaning that the fingerprints ridges will grow wider until
they finally overlap. This would make
them unusable and inadmissible as evidence. Fingerprint evidence is analysed by a
fingerprint expert who will compare it to fingerprints held on the national
database for fingerprints, palm prints and crime scene marks, IDENT1, or those
taken from a suspect.
In the case of Aileen Wuornos the biological sample of hair
would have been analysed in order to determine if a DNA profile could be obtained
from the hair root bulb, if attached, which could have been used to make a
positive match to a suspect, if not, the hair would be classed as trace
evidence and it could only be stated that the sample is a match to the colour
and possible length of a suspects. The
discarded condom packet would have been analysed to discover any latent
fingerprints or saliva that could be used to make a positive match to a
suspect.
All the vehicles recovered in the Aileen Wuornos case would
have been transported to the forensic facility/garage by a reputable company
trusted by the police to handle such evidence appropriately. They would then have been inspected by a
forensic scientist in order to determine the presence of any evidence.
Aileen Wuornos was under surveillance by the police who
recorded her movements and had placed a telephone tap on Tyria Moore’s phone
line in order to record her telephone conversations in the hope that Wuornos would
confess to the killings to Moore.
The results obtained from all forensic tests would be
thoroughly documented for use by the police, courts and as a permanent record
that can be referred to when required.
A case file containing all the records relating to the
criminal investigation which would include the initial crime scene assessment, entry
log, sketches/photographs, evidence, witness statements, results from forensic
testing on evidence which presents a case that the person suspected and in
custody is responsible for the crime and should be charged. This is presented to the Crown Prosecution
Service (CPS) who are responsible for deciding if the case file contains enough
evidence to warrant the suspect being charged.
If so the forensic scientist can be called to give evidence as an expert
witness in relation to how the evidence was collected and analysed and the
results obtained. The investigating
officer in charge of the case may be called to give his/her evidence in
relation to his/her interpretation of the evidence which would include the
statements obtained from witnesses, if any, and the suspect/s statement.
In the case of Aileen Wuornos the case file would have been
handed to the District Attorney, John Tanner, who would make the decision on
whether there was enough evidence to charge the suspect. Aileen Wuornos was indicted for murder on the
28th January 1991, following her arrest on the 9th
January 1991, at the Supreme Court of Florida and a trial date set for the 14th
January 1992 with Judge Uriel Blount presiding over the case who chose to come out of retirement specifically
to try the case.
As no record can be obtained it is presumed that the scenes
of crime officers (SOCO’s) did wear the appropriate Personal Protective
Equipment (PPE) when attending the crime scene however if the (PPE) is not worn
when collecting evidence that evidence can be deemed inadmissible due to
possible contamination which could have a detrimental effect on the outcome of
the case when/if presented to a court of law.
The witness statements taken in the Aileen Wuornos case were
proved to be accurate however the downside of using witness statements are that
they can be biased or confused especially if a period of time has elapsed between
the sighting and the taking of the witness statement.
There were obvious floors in the investigation of the crime
scenes in the Aileen Wuornos case as evidence was missed, a scandal regarding
film deals with two police officers and Tyria Moore which could have prejudiced
the case against Wuornos prior to the trial commencing and the fact that
Richard Mallory’s criminal record relating to the attack of a woman was deemed irrelevant
even though Wuornos claimed she acted in self defence as Mallory had attacked
her. Wuornos’s horrific background of alleged
neglect and physical abuse was not presented to the jury which could have been
presented as mitigating circumstances for the crimes she committed.
No comments:
Post a Comment