Criminology Unit 3: Crime scene to courtroom
AC1.1 - Evaluate the effectiveness of the roles of personal involved
in criminal investigations
Scenes of crime officers (crime scene investigators):
These officers are employed by the police
Preserve and protect the scene
Recover evidence – by taking photos and videos
Ensure evidence is not contaminated
Collects evidence ASAP
Search for things like gunshot residue, fingerprints, hairs and fibers.
Contaminated evidence is inadmissible in court
SOCOs are trained and qualified for this role
On-call system
Prevent unauthorized access to the crime scene.
Cost, expertise and availability:
- Average salary £16,000 to £37,000
- Degree in psychology, forensics, criminology or science
- 2-3 A levels needed or equivalent
- May be able to enter through police college
- High-cost equipment because of the advanced technical nature of the tests made.
- Highly paid professionals as very highly trained
Strengths
- Experts at collecting evidence
- When collected correctly, can help to conclusively link suspects to a crime or
eliminate them from the investigation
- Allow other professionals to get on with their important tasks of analysing and
investigating leads.
- 68% of respondents to the crime scene are SOCOs (Unison.org.uk)
- “a statistically significant increase in acquittal rates from the year's pre-CSI to post-
2001 and post-2002, but not post-2003” (Cole & Dioso-Vila)
- Risks can be minimized by the wearing of protective clothing, including masks and
glasses.
Limitations
- May be exposed to hazardous substances in their role, such as contaminants
contacting the skin or airborne substances that could enter the mouth.
- High turnover of staff – decreases availability of SOCOs which may result in evidence
collection being rushed and not completed to the standard
- SOCOs are one of the most commonly reported job losses according to unison.org.uk
- Case study Amanda Knox: In 2007, Meredith Kercher was found murdered in Italy -
allegedly by Amanda Knox. During the investigation, there was contamination at the
, crime scene which allowed lawyers to suggest that the evidence collected was
unreliable. Not all the officers wore protective clothing inside and outside the house
which could have caused contamination. Knox was originally charged and put in
prison for the crime in the original trial- however the retrial allowed the Knox’s
defence team to point out the issues with crime scene contamination
Forensic scientists:
Review evidence from a crime scene
Produce information for a court
Evidence such as blood and other body fluids are analyzed in a laboratory and
interpreted.
The information they gather can be used to assist the court in deciding and
producing a just result.
Specialisms – DNA analysis, toxicology, computing forensic anthropology, fire
analysis and psychology.
Cost, expertise and availability:
- High level of expertise
- A-levels in Biology, Chemistry, Maths and possibly Computer Science
- Minimum qualification of first degree in a science subject
- Some have a PhD in their chosen specialty
- Very high cost – due to equipment and technology
- The availability of staff is low.
- They are paid between £20,000-£35,000 per year and senior levels can reach
£50,000 or more.
Strengths
- High level of expertise means they are needed to help in complex cases so that
suspects can be conclusively linked or excluded from investigations.
- Hard to detect evidence can be found meaning they can detect small details using
the complex technology
- e.g. microscopic traces of fibres were the key to convicting two men for the murder
of Stephen Lawrence.
- They take samples collected by the SOCOs at the crime scene to a
Limitations
- Some believe that DNA analysis of a person can be against human ethics.
- It can be expensive and time-consuming
- If care and attention is not present, a miscarriage of justice could occur.
- The Jury may believe the evidence is true as they are an expert in their field even if
the scientist may have made a mistake.
- Case study: Adam Scott, a plastic tray that contained his DNA had not been
disposed of and was reused in a rape case. This mistake resulted in him being in
custody for five months.
- Case study: Amanda Knox, In the murder of Meridith Kercher, there was a
contamination of DNA which led to the conviction of Amanda Knox – which was a
, mistrial of justice and later was overturned by a different forensic scientist who
discredited this evidence.
Police officers:
First on the scene
The first job is to preserve life but also to secure the crime scene so that evidence
can be conserved.
Attend to anyone injured
Ensure nobody contaminates the crime scene
Arrest any suspects
Trained professionals who investigate crime and attempt to reduce fear.
There are specialist units in the police service, including the CID, firearms,
underwater etc.
The CID are detectives not constables
Cost, expertise and availability:
- High level of training
- High level of expertise
- The police officers must receive 2 years of training first to become officers – then to
become detective they must go through special exams to qualify.
- Constables cost up to £60,812 per year
- Officers can cost up to £27.3 billion in the UK in 2023/24
- Police constables can earn £37,124 per year
- Low availability of police officers due to high turnover, sickness and stress as well as
lack of recruitment,
- Many officers call in sick due to stress
- Availability of specialist officers is even lower
Strengths
- Experts in investigations of crime
- Highly trained and deal with complex or serious crime.
- Allows other professionals to focus on their role as the police officers
apprehend and arrest the suspect/s.
-
Limitations
, - Sometimes the police carry out poor investigations or they do not thoroughly
investigate, (e.g. in the Damilola Taylor case where they did not detect lies
from a witness which seemed to be obvious)
- Fail to secure crime scenes in some cases leads to miscarriages of justice.
- Case study: Stephen Lawrence, the Macpherson Report (1999), issued because
of the Lawrence case, said that the police had institutional racism and made 70
recommendations to improve the service. E.G. police officers failed to administer first
aid which could have possibly saved his life, and they interviewed Stephen’s friend
11 days (about 1 and a half weeks) after the killing.
- The Hillsborough disaster also shows that the police can act inappropriately in
criminal investigations. The inquest in 2016 concluded that blunders by the police
caused or contributed to the disaster and that victims had been unlawfully killed.
Crown prosecution service (CPS):
Set up in 1986
Independent prosecution agency to take over from the police
Advises police on cases for possible prosecution.
Ultimately decides whether to prosecute,
CPS works with the police to help avoid bias.
CPS is effectively a law firm with over 2,000 crown prosecutors (fully qualified
barristers and solicitors.
Apply tests to allow consistency – consider the evidence collected by the police and
whether it is in the public interest to prosecute.
Advice is available 24 hours a day from CPS direct.
Cost, expertise and availability
- High level of expertise – with multiple specialist divisions (e.g. terrorism, complex
fraud, organized crime)
- Prosecutors must be qualified solicitors or barristers, have completed their Legal
Practice Course or Bar Vocational Course and the two-year training contract.
- Very high cost, staffing and running costs.
- Low availability – severe shortages of lawyers.
Strengths
- Separation of crime investigation from prosecution.
- Justice is more impartial than before 1986 when the police were in charge or
charging and prosecuting.
- Expert divisions require specialist knowledge, meaning they can pursue complex
cases that are beyond the level or expertise of any police force.
Limitations
- In the past many cases have collapsed due to lack of evidence
AC1.1 - Evaluate the effectiveness of the roles of personal involved
in criminal investigations
Scenes of crime officers (crime scene investigators):
These officers are employed by the police
Preserve and protect the scene
Recover evidence – by taking photos and videos
Ensure evidence is not contaminated
Collects evidence ASAP
Search for things like gunshot residue, fingerprints, hairs and fibers.
Contaminated evidence is inadmissible in court
SOCOs are trained and qualified for this role
On-call system
Prevent unauthorized access to the crime scene.
Cost, expertise and availability:
- Average salary £16,000 to £37,000
- Degree in psychology, forensics, criminology or science
- 2-3 A levels needed or equivalent
- May be able to enter through police college
- High-cost equipment because of the advanced technical nature of the tests made.
- Highly paid professionals as very highly trained
Strengths
- Experts at collecting evidence
- When collected correctly, can help to conclusively link suspects to a crime or
eliminate them from the investigation
- Allow other professionals to get on with their important tasks of analysing and
investigating leads.
- 68% of respondents to the crime scene are SOCOs (Unison.org.uk)
- “a statistically significant increase in acquittal rates from the year's pre-CSI to post-
2001 and post-2002, but not post-2003” (Cole & Dioso-Vila)
- Risks can be minimized by the wearing of protective clothing, including masks and
glasses.
Limitations
- May be exposed to hazardous substances in their role, such as contaminants
contacting the skin or airborne substances that could enter the mouth.
- High turnover of staff – decreases availability of SOCOs which may result in evidence
collection being rushed and not completed to the standard
- SOCOs are one of the most commonly reported job losses according to unison.org.uk
- Case study Amanda Knox: In 2007, Meredith Kercher was found murdered in Italy -
allegedly by Amanda Knox. During the investigation, there was contamination at the
, crime scene which allowed lawyers to suggest that the evidence collected was
unreliable. Not all the officers wore protective clothing inside and outside the house
which could have caused contamination. Knox was originally charged and put in
prison for the crime in the original trial- however the retrial allowed the Knox’s
defence team to point out the issues with crime scene contamination
Forensic scientists:
Review evidence from a crime scene
Produce information for a court
Evidence such as blood and other body fluids are analyzed in a laboratory and
interpreted.
The information they gather can be used to assist the court in deciding and
producing a just result.
Specialisms – DNA analysis, toxicology, computing forensic anthropology, fire
analysis and psychology.
Cost, expertise and availability:
- High level of expertise
- A-levels in Biology, Chemistry, Maths and possibly Computer Science
- Minimum qualification of first degree in a science subject
- Some have a PhD in their chosen specialty
- Very high cost – due to equipment and technology
- The availability of staff is low.
- They are paid between £20,000-£35,000 per year and senior levels can reach
£50,000 or more.
Strengths
- High level of expertise means they are needed to help in complex cases so that
suspects can be conclusively linked or excluded from investigations.
- Hard to detect evidence can be found meaning they can detect small details using
the complex technology
- e.g. microscopic traces of fibres were the key to convicting two men for the murder
of Stephen Lawrence.
- They take samples collected by the SOCOs at the crime scene to a
Limitations
- Some believe that DNA analysis of a person can be against human ethics.
- It can be expensive and time-consuming
- If care and attention is not present, a miscarriage of justice could occur.
- The Jury may believe the evidence is true as they are an expert in their field even if
the scientist may have made a mistake.
- Case study: Adam Scott, a plastic tray that contained his DNA had not been
disposed of and was reused in a rape case. This mistake resulted in him being in
custody for five months.
- Case study: Amanda Knox, In the murder of Meridith Kercher, there was a
contamination of DNA which led to the conviction of Amanda Knox – which was a
, mistrial of justice and later was overturned by a different forensic scientist who
discredited this evidence.
Police officers:
First on the scene
The first job is to preserve life but also to secure the crime scene so that evidence
can be conserved.
Attend to anyone injured
Ensure nobody contaminates the crime scene
Arrest any suspects
Trained professionals who investigate crime and attempt to reduce fear.
There are specialist units in the police service, including the CID, firearms,
underwater etc.
The CID are detectives not constables
Cost, expertise and availability:
- High level of training
- High level of expertise
- The police officers must receive 2 years of training first to become officers – then to
become detective they must go through special exams to qualify.
- Constables cost up to £60,812 per year
- Officers can cost up to £27.3 billion in the UK in 2023/24
- Police constables can earn £37,124 per year
- Low availability of police officers due to high turnover, sickness and stress as well as
lack of recruitment,
- Many officers call in sick due to stress
- Availability of specialist officers is even lower
Strengths
- Experts in investigations of crime
- Highly trained and deal with complex or serious crime.
- Allows other professionals to focus on their role as the police officers
apprehend and arrest the suspect/s.
-
Limitations
, - Sometimes the police carry out poor investigations or they do not thoroughly
investigate, (e.g. in the Damilola Taylor case where they did not detect lies
from a witness which seemed to be obvious)
- Fail to secure crime scenes in some cases leads to miscarriages of justice.
- Case study: Stephen Lawrence, the Macpherson Report (1999), issued because
of the Lawrence case, said that the police had institutional racism and made 70
recommendations to improve the service. E.G. police officers failed to administer first
aid which could have possibly saved his life, and they interviewed Stephen’s friend
11 days (about 1 and a half weeks) after the killing.
- The Hillsborough disaster also shows that the police can act inappropriately in
criminal investigations. The inquest in 2016 concluded that blunders by the police
caused or contributed to the disaster and that victims had been unlawfully killed.
Crown prosecution service (CPS):
Set up in 1986
Independent prosecution agency to take over from the police
Advises police on cases for possible prosecution.
Ultimately decides whether to prosecute,
CPS works with the police to help avoid bias.
CPS is effectively a law firm with over 2,000 crown prosecutors (fully qualified
barristers and solicitors.
Apply tests to allow consistency – consider the evidence collected by the police and
whether it is in the public interest to prosecute.
Advice is available 24 hours a day from CPS direct.
Cost, expertise and availability
- High level of expertise – with multiple specialist divisions (e.g. terrorism, complex
fraud, organized crime)
- Prosecutors must be qualified solicitors or barristers, have completed their Legal
Practice Course or Bar Vocational Course and the two-year training contract.
- Very high cost, staffing and running costs.
- Low availability – severe shortages of lawyers.
Strengths
- Separation of crime investigation from prosecution.
- Justice is more impartial than before 1986 when the police were in charge or
charging and prosecuting.
- Expert divisions require specialist knowledge, meaning they can pursue complex
cases that are beyond the level or expertise of any police force.
Limitations
- In the past many cases have collapsed due to lack of evidence
