1
CRIMINOLOGY
UNIT 3 NOTES
LATEST WITH
SUMMARY
(100% WELL
ENLIGHTENED
2026)
, 2
TABLE OF CONTENTS
1. ac 1.1 – evaluate the effectiveness of the roles of personnel involved in criminal investigations.
(10 marks)
2. ac 1.2 assess the usefulness of the investigative techniques in criminal investigations (20 marks)
3. ac1.3 explain how evidence is processed (6 marks)
4. ac 1.4 examine the rights of individuals in criminal investigations (6 marks)
5. ac 2.1 explain the requirements of the crown prosecution service(cps) for prosecuting suspects (4
marks)
6. ac 2.2 describe trial processes (4 marks)
7. ac 2.3 understand rules in relation to the use of evidence in criminal cases (4 marks)
8. ac 2.4 assess key influences affecting the outcomes of criminal cases (10 marks)
9. ac2.5 discuss the use of lay people in criminal cases (6 marks)
10. ac 3.1 examine information for validity(15 marks)
11. ac 3.2 draw conclusions from information (15 marks)
, 3
ac 1.1 - evaluatethe effectiveness of theroles of personnel involved incriminal investigations.
(10 marks)
crime scene investigators
role:
a crime scene investigators role is to collect and preserve evidence from the crime scene. they
main responsibility is to ensure that the evidence at the scene is not contaminated as tis would
therefore mean it will not be admissible in court. 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
haveobtained all the evidence, they have to pack and document everything so it is ready to be
sent off for analysis by for ensicspecialists. in addition to this, the may also attend post mortems
and give evidence in court.
effectiveness:
expertise- csis are experts in their fieldas they undergo through training and many also have
adegree 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- ciss 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 its important that crime scene investigators can arrive at the scene
quickly in order to obtain evidence beforeit may be possiblycontaminated by factors such as the
weather.
cost- each csi gets paid a salary, and so this will therefore incur additionalcosts to the investigation.
otherevaluativepoints:
• the samples that csi‟s collect may be ahazard to their health and safety, so these rusks
need to be calculated and the appropriate measurestaken in order to minimize the risk of
harm
• the role can be taking 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 provide asuspect‟s innocence throughdna orfingerprints testing.
case example- amanda knox:
• exchange student founddead in herflat in italy, friend knoxsuspectedof murder.
• contamination of evidence, failures to document evidence, planted evidence to
falsely incriminate
strength
• ciss may gather evidence that conclusivelylinks suspects to crime scenesand victims
• the evidence may also proveconclusively that asuspect is in fact innocent, e.g., when
their fingerprints do not match those found by the csi at the crime scene
limitations
• the work requires specialist skills (such as forensicphotography), as well as patience,
, 4
meticulous care and attention to detail. failure to collect and record evidence correctly,
or allowing it to become contaminated, can lead to a guilty person going free or an
innocent one being convicted.
• the forensicsamplesthat csis handle may out their health orsafety at risk. these
includeblood and other body fluids, hazardouschemicals, explosives and
incendiarydevices, firearms and ammunition, knives and hypodermic syringes.
• the work may be stressful and emotionally demanding. this can lead to burn-out and
people leaving the profession, resulting in staff shortages.
forensics specialists and 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 analyze arange 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 evidencewhich couldlead to proving if asuspect is
innocent orguilty, 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 analyzed
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, someforensicscientistswork on an
on-call basis, which means that they can work on high priority cases as they unfold
whichwouldgreatly help the investigateprocess.
cost- as forensicscientistsare 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 woul d be analyzed as its might not be financiallyfeasible.
otherevaluative points-
• the work that forensics 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 defense and prosecution‟sexpertsmay give conflictingevidence
which would confuse the jury and make it more difficult for them to come to a verdict
• an expert, such as a forensicscientist, couldmislead the court, whether it be on purpose
or as a result of a mistake is wrongly found guilty or not guilty. an example of this is the
case of sally clarke who was found guilty for murdersshe did not commit as aresult of an
expert‟s mistake.
• issue of contamination – if evidence us contaminated in the analysis process this can
cause issues such as evidencebeing mixedup or incorrectly interpreted. this of
CRIMINOLOGY
UNIT 3 NOTES
LATEST WITH
SUMMARY
(100% WELL
ENLIGHTENED
2026)
, 2
TABLE OF CONTENTS
1. ac 1.1 – evaluate the effectiveness of the roles of personnel involved in criminal investigations.
(10 marks)
2. ac 1.2 assess the usefulness of the investigative techniques in criminal investigations (20 marks)
3. ac1.3 explain how evidence is processed (6 marks)
4. ac 1.4 examine the rights of individuals in criminal investigations (6 marks)
5. ac 2.1 explain the requirements of the crown prosecution service(cps) for prosecuting suspects (4
marks)
6. ac 2.2 describe trial processes (4 marks)
7. ac 2.3 understand rules in relation to the use of evidence in criminal cases (4 marks)
8. ac 2.4 assess key influences affecting the outcomes of criminal cases (10 marks)
9. ac2.5 discuss the use of lay people in criminal cases (6 marks)
10. ac 3.1 examine information for validity(15 marks)
11. ac 3.2 draw conclusions from information (15 marks)
, 3
ac 1.1 - evaluatethe effectiveness of theroles of personnel involved incriminal investigations.
(10 marks)
crime scene investigators
role:
a crime scene investigators role is to collect and preserve evidence from the crime scene. they
main responsibility is to ensure that the evidence at the scene is not contaminated as tis would
therefore mean it will not be admissible in court. 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
haveobtained all the evidence, they have to pack and document everything so it is ready to be
sent off for analysis by for ensicspecialists. in addition to this, the may also attend post mortems
and give evidence in court.
effectiveness:
expertise- csis are experts in their fieldas they undergo through training and many also have
adegree 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- ciss 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 its important that crime scene investigators can arrive at the scene
quickly in order to obtain evidence beforeit may be possiblycontaminated by factors such as the
weather.
cost- each csi gets paid a salary, and so this will therefore incur additionalcosts to the investigation.
otherevaluativepoints:
• the samples that csi‟s collect may be ahazard to their health and safety, so these rusks
need to be calculated and the appropriate measurestaken in order to minimize the risk of
harm
• the role can be taking 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 provide asuspect‟s innocence throughdna orfingerprints testing.
case example- amanda knox:
• exchange student founddead in herflat in italy, friend knoxsuspectedof murder.
• contamination of evidence, failures to document evidence, planted evidence to
falsely incriminate
strength
• ciss may gather evidence that conclusivelylinks suspects to crime scenesand victims
• the evidence may also proveconclusively that asuspect is in fact innocent, e.g., when
their fingerprints do not match those found by the csi at the crime scene
limitations
• the work requires specialist skills (such as forensicphotography), as well as patience,
, 4
meticulous care and attention to detail. failure to collect and record evidence correctly,
or allowing it to become contaminated, can lead to a guilty person going free or an
innocent one being convicted.
• the forensicsamplesthat csis handle may out their health orsafety at risk. these
includeblood and other body fluids, hazardouschemicals, explosives and
incendiarydevices, firearms and ammunition, knives and hypodermic syringes.
• the work may be stressful and emotionally demanding. this can lead to burn-out and
people leaving the profession, resulting in staff shortages.
forensics specialists and 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 analyze arange 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 evidencewhich couldlead to proving if asuspect is
innocent orguilty, 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 analyzed
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, someforensicscientistswork on an
on-call basis, which means that they can work on high priority cases as they unfold
whichwouldgreatly help the investigateprocess.
cost- as forensicscientistsare 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 woul d be analyzed as its might not be financiallyfeasible.
otherevaluative points-
• the work that forensics 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 defense and prosecution‟sexpertsmay give conflictingevidence
which would confuse the jury and make it more difficult for them to come to a verdict
• an expert, such as a forensicscientist, couldmislead the court, whether it be on purpose
or as a result of a mistake is wrongly found guilty or not guilty. an example of this is the
case of sally clarke who was found guilty for murdersshe did not commit as aresult of an
expert‟s mistake.
• issue of contamination – if evidence us contaminated in the analysis process this can
cause issues such as evidencebeing mixedup or incorrectly interpreted. this of
