AC 1.1 - Evaluate the effectiveness of the roles of personnel involved in
criminal investigations
Crime Scene Investigators
Role
A crime scene investigators role is to collect and preserve evidence from the crime scene.
Their main responsibility is to ensure that the evidence at the scene is not contaminated as
this would therefore mean it would be inadmissible in court. They work together with the
police to decide what evidence is vital and decide the best way in order to gather it. They
photograph the crime scene, as well as any surrounding areas that contain evidence, using
the common approach path. Once they have obtained all the evidence, they have to pack
and document everything so it is ready to be sent off for analysis by forensic specialists. In
addition to this, they may also attend post mortems and give evidence in court.
Effectiveness
Expertise - CSI’s are experts in their field as they undergo thorough training and many also
have a degree in a science related field. This would imply that they have a great deal of
expertise as they have had the necessary training in order to carry out their role effectively.
Availability - CSI’s are available 24/7 as they work on an on-call basis. This means that they
could be called to a crime scene at any time of the day. This is essential as of course crimes
can be committed at any time, and so it is important that crime scene investigators can arrive
at the scene quickly in order to obtain evidence before it may be possibly contaminated by
factors such as the weather.
Cost - Each CSI gets paid a salary, and so this will therefore incur additional costs to the
investigation.
Other evaluative points
- The samples that CSI’s collect may be a hazard to their health and safety, so these
risks need to be calculated and the appropriate measures taken in order to minimise
the risk of harm
- The role can take a toll on CSI’s mental wellbeing due to the nature of the scenes
that they may attend to.
- The weather could contaminate the crime scene
- They may be able to prove a suspect's innocence through DNA or fingerprint testing.
Case Example - Amanda Knox
- Exchange student found dead in her flat in Italy, friend Knox suspected of murder.
- Contamination of evidence, failures to document evidence, planted evidence to
falsely incriminate
Forensic Specialists & Scientists
Role
Once evidence has been collected from the crime scene by CSI’s, it is passed over to the
Forensic Specialists and Scientists. Their role is to interpret and analyse the evidence in
relation to the crime scene. They analyse a range of evidence, such as blood and other
bodily fluids, in order to try and find DNA. This is the aim of most evidence analysis, as
,finding DNA means the person responsible for the crime is often identified and found.
Effectiveness
Expertise - Forensic scientists possess a great deal of specialist knowledge that is vital in
investigations. They are able to interpret evidence which could lead to proving if a suspect is
innocent or guilty, so they have a big role to play within an investigation. This expertise is
especially valuable in complicated and advanced criminal cases, as the criminal may also
possess knowledge which prevents evidence being linked to them.
Availability - Forensic scientists typically work during the normal working week, which is
Monday to Friday. This could be an issue as some cases may require evidence to be
analysed urgently in order to catch the suspect as soon as possible, and so waiting for a
forensic scientist to be available would cause delays in the investigation. However, some
forensic scientists work on an on-call basis, which means that they can work on high priority
cases as they unfold which would greatly help the investigative process.
Cost - As forensic scientists are highly qualified individuals, this also means that their
salaries and work they provide is expensive. This would mean that the use of forensic
scientists in investigations would increase the cost of the investigation overall, and perhaps
means that not all evidence would be analysed as it might not be financially feasible.
Other evaluative points
- The work that forensic scientists do is subjective, and thus that means that different
forensic scientists may interpret evidence differently. This could cause issues in the
courtroom, as the defence and prosecution’s experts may give conflicting evidence
which would confuse the jury and make it more difficult for them to come to a verdict.
- An expert, such as a forensic scientist, could mislead the court, whether it be on
purpose or as a result of a mistake in their work. This ultimately leads to miscarriages
of justice where either the suspect is wrongly found guilty or not guilty. An example of
this is the case of Sally Clarke who was found guilty for murders she did not commit
as a result of an expert's mistake.
- Issue of contamination - If evidence is contaminated in the analysis process this can
cause issues such as evidence being mixed up or incorrectly interpreted. This of
course would lead to problems with the investigation, perhaps in accusing the wrong
suspect or letting someone go due to the evidence surrounding them being lost.
Case Example - Sally Clarke
- Wrongly convicted of the murder of her two sons as a result of the expert witness,
Professor Sir Roy Meadows, giving evidence that was based on wrong information
(See AC3.2 for more detail)
Case Example - Adam Scott
- Falsely accused of rape after his DNA was contaminated, leading him to spend 5
months in custody charged with rape. This shows how contamination of evidence can
affect a criminal investigation.
Case Example - Sarah Payne
- Sarah Payne was a young girl was abducted and murdered by a previously convicted
pedophile Roy Whiting
- Used fibers from sweatshirt found in van to link to the presence of Sarah there, found
threads of school uniform on Velcro shoes
- A number of clothing fibres and a single strand of Sarah's hair were linked to items in
, the van used by Mr Whiting to take the eight-year-old before driving her more than 20
miles to dump her naked body.
Police Officers & Detectives
Role
Police officers are most commonly the first people to arrive at a crime scene. Their first duty
is to ensure the wellbeing of anyone involved, for example by calling an ambulance or
keeping the public away from the scene for their safety. If the suspect is still present, they
should aim to arrest them. After this has been established, the police officers role is to make
sure that the evidence at the scene is conserved until a CSI is available to gather it. They do
this by ensuring that nobody enters the scene or touches anything that could be classed as
evidence. They may also take witness statements from people who saw the crime take
place, and this needs to be done as soon as possible to avoid issues of witnesses forgetting
or being confused as to what they saw. Detectives have a similar role, but they have a more
managerial role, meaning they oversee what happens at the scene initially and talk to the
officers to gather the information they need to begin their investigation.
Effectiveness
Availability - Police officers work on an on-call basis, meaning they are available to attend to
crime scenes 24 hours a day, 7 days a week. This is vital as it means criminals are more
likely to be arrested at the scene which saves time in trying to identify and locate them at a
later date.
Expertise - Police officers undergo training to ensure that they are fit to carry out their role
and so they have specialist knowledge to be able to deal with a crime scene. Detectives
have many years of experience in order to obtain the rank of detective, and they often work
in specialist departments which ensures that they are equipped to investigate and deal with
the crime at hand.
Cost - Both police officers and detectives get paid a yearly salary which incurs costs.
Other evaluative points
- Police could fail to secure a crime scene, which could possibly result in the
contamination of evidence, and this would severely hinder the case in court.
- Certain crimes may not be taken as seriously by the police, or because of personal
biases
- Issues such as institutional racism in the police force show incompetence and
discriminatory attitudes among the police. This affects crime scene procedures as
they may make assumptions about the offender or victim which could lead to
evidence being overlooked or the crime not being investigated correctly (Stephen
Lawrence case)
Case Example - Stephen Lawrence
- Racially motivated attack resulting in the death of Lawrence whilst walking home.
- Failed to be recognized as a hate crime due to the institutional bias and racism of the
police service and failures to investigate suspects due to force corruption
Crown Prosecution Service
Role
The CPS is a prosecution service which covers England and Wales, made up of 2,000
solicitors and barristers, as well as assisting staff. Its main function is to advise the police on
, the likelihood of prosecution if a case is brought to court. They also test to see if there is
sufficient evidence for prosecution, and if the case is in the public interests. The CPS can
decide what charge to give an offender in more serious cases. They also have a role in the
court proceedings, as they prepare cases for hearings and make sure all the relevant
information is disclosed to the defence, and may also present the case in court.
Effectiveness
Availability - The CPS have a service in place called ‘CPS Direct’, which operates a 24/7
service which is easily accessible over the phone for the police to utilise, meaning they can
have suspects charged as soon as possible without the CPS delaying them.
Expertise - The CPS is composed of many highly qualified professionals. The main staff
include solicitors and barristers, who have excellent knowledge of the law and court
proceedings which is essential in advising the police correctly. There are also clerks who
ensure that all the documents are ready for court.
Cost - Due to the amount of staff employed to ensure the CPS can operate efficiently, the
running of the service is expensive. However, it may also reduce the cost in court, as less
cases are thrown out of court due to the CPS’ work to ensure cases are ready for court.
Other evaluative points
- There is no longer a bias in investigating cases, as previously the police used to be in
charge of investigating, charging and prosecuting cases, but now the CPS ensures
that cases are handled independently and it is more fair on the individual suspects
- There is more consistency as there is one body which oversees all prosecution in
England and Wales
- The CPS can reject the police's request to prosecute someone, this can lead to
issues in the relationship between them.
- Errors can occur as a result of the CPS’ fault, which could happen if the evidence is
not reviewed thoroughly enough before making the decision to prosecute. (Damilola
Taylor)
Case Example - Damilola Taylor
- Taylor was a 10 year old schoolboy found dead from a leg wound
- The case underwent a lengthy trial spanning 6 years and including 3 trials before
convicting 2 brothers.
- Prosecution's case was filled with holes and heavily reliant on unreliable witnesses.
This shows the CPS’ failure to ensure the case was ready to go to court
Pathologists
Role
Pathologists are doctors who are specialists in examining the causes of disease and death.
They carry out post mortem examinations where they examine the dead body to establish
how and when they died. They examine things such as internal organs, marks on the skin
and take tissue samples so they can be analysed in a laboratory. A different pathologist,
from the defence, will also carry out the same examination. After the post mortems are
complete, the pathologist will write a report for the coroner and a statement for the police.
They may also be asked to present their findings in court if necessary.
Effectiveness
Availability - In a suspected murder, the Home Office will assign a pathologist to work
