Harrison Naylor
Unit 3 1.2
Forensics
One technique used in an investigation is Forensics. Evidence collected at
the crime scene is analysed by experts. They use the UK National DNA
Database and the Police National Computer (PNC) to match evidence
found at the crime scene in the hopes to identify the criminal. The
National DNA database holds DNA profiles and relevant samples for a
limited period. For example, as of 2023, the DNA profiles of approximately
5.7 million individuals was held. The PNC collects and holds data on
people, vehicles, criminal history and properties. It is used to carry out
real-time checks.
An advantage of forensics is that everyone’s DNA profile is unique. This is
a strength as once this profile can be matched with another on the
database; there is admissible evidence to convict a suspect. DNA cannot
be altered; therefore, this evidence is strong and credible. An example of
this is the Colin Pitchfork case. This was the first time DNA profiling was
used in a criminal investigation. Authorities gathered DNA from
approximately 5000 local men. Pitchfork then pleaded guilty to the
murders and rape cases. This exemplifies how useful DNA evidence is in a
case. Another strength of forensics is that familial DNA can also be used in
cases. Rather than a direct match, the DNA profile will be significantly
similar as people share 50% of their DNA with their parents. This is a
strength as it can help convict people who are not on the National DNA
Database. This was evidenced in the Colette Aram case. She was
abducted, raped and murdered. As evidence analysation advanced,
biological evidence that had been preserved was tested. However, for
years this DNA did not match anyone. This was until Hutchinson’s son was
arrested for a motoring offence. His DNA was taken, and it provided a
familial match to Paul Hutchinson, the killer, whose DNA found on a paper
towel in a pub nearby had been preserved for 25 years. This portrays the
usefulness of familial DNA. A third strength of forensics is that it can help
solve old cases, bringing justice to offenders and comfort to victims. As
technology advanced, so did forensic science. This means that evidence
that could not be analysed in the past can be used now to close cases.
731,000 matches of unsolved crimes were solved from 2001 to 2020
because of the advancements made. However, a disadvantage is that if
the DNA profile found as evidence is not on the National Database, the
offender cannot be convicted. This is a disadvantage as the offender will
, Harrison Naylor
be able to continue committing these crimes. For example, Robert
Napper, who committed multiple murders and rapes, was able to evade
the authorities as DNA found at the scenes did not match any on the
database as he had never been convicted of a crime before. This meant
he was able to continue committing crime. Another weakness is that
human error is a possibility. For example, cross contamination of evidence
can occur, meaning people can be wrongfully convicted for crimes they
did not commit, which is unjust. An example of this is the Randox Scandal.
The Randox Testing Services in Manchester (a private forensics lab) dealt
with toxicology and mostly drug driving tests for authorities in the UK.
Staff at the lab had manipulated results and over 10,000 criminal cases
were affected. This ruined people's lives, giving them criminal records and
even causing them to lose their job in some circumstances. A third
weakness is that people still get convicted of crimes that they did not
commit. An example of this is the David Butler case. The DNA sample
used to convict him was only a partial match and was poor quality, yet
was still used to convict him, which is unfair and is a weakness of
forensics in criminal investigations.
One type of case that forensics is useful in is sexual offences. This is
because the offender typically leaves behind biological evidence (blood,
skin cells, semen). This is analysed in laboratories and a swab from the
offender at the station will be taken to search for a match. It may also be
useful in murder cases. During the investigation, blood may be found if
there was some struggle, skin cells may be found under the victim's
fingernails, and the murder weapon may have the offenders DNA on. This
is also analysed in a lab, and a swab will be taken from the offender.
Furthermore, DNA is also useful when investigating burglaries. It can be
collected at the crime scene. Fingerprint analysis could also be used if it is
evident that the offender did not wear gloves. Regardless of this
usefulness, forensics may not be useful in other types of crime. For
example, it would not be useful when investigating a cybercrime as DNA is
not transferred online. This is a disadvantage as crimes like fraud can be
carried out online, where forensics cannot be used to convict the offender,
making it easier to evade authorities.
Interviews
Another technique used in criminal investigations is interviews. This
involves making a detailed account of an event from a person the police
believe to have knowledge that may be relevant to the case that they are
investigating. Eyewitness testimonies (EWT) are given by people who
spectated a crime. Most investigations rely on eyewitness testimonies to
understand how the event derived.
Unit 3 1.2
Forensics
One technique used in an investigation is Forensics. Evidence collected at
the crime scene is analysed by experts. They use the UK National DNA
Database and the Police National Computer (PNC) to match evidence
found at the crime scene in the hopes to identify the criminal. The
National DNA database holds DNA profiles and relevant samples for a
limited period. For example, as of 2023, the DNA profiles of approximately
5.7 million individuals was held. The PNC collects and holds data on
people, vehicles, criminal history and properties. It is used to carry out
real-time checks.
An advantage of forensics is that everyone’s DNA profile is unique. This is
a strength as once this profile can be matched with another on the
database; there is admissible evidence to convict a suspect. DNA cannot
be altered; therefore, this evidence is strong and credible. An example of
this is the Colin Pitchfork case. This was the first time DNA profiling was
used in a criminal investigation. Authorities gathered DNA from
approximately 5000 local men. Pitchfork then pleaded guilty to the
murders and rape cases. This exemplifies how useful DNA evidence is in a
case. Another strength of forensics is that familial DNA can also be used in
cases. Rather than a direct match, the DNA profile will be significantly
similar as people share 50% of their DNA with their parents. This is a
strength as it can help convict people who are not on the National DNA
Database. This was evidenced in the Colette Aram case. She was
abducted, raped and murdered. As evidence analysation advanced,
biological evidence that had been preserved was tested. However, for
years this DNA did not match anyone. This was until Hutchinson’s son was
arrested for a motoring offence. His DNA was taken, and it provided a
familial match to Paul Hutchinson, the killer, whose DNA found on a paper
towel in a pub nearby had been preserved for 25 years. This portrays the
usefulness of familial DNA. A third strength of forensics is that it can help
solve old cases, bringing justice to offenders and comfort to victims. As
technology advanced, so did forensic science. This means that evidence
that could not be analysed in the past can be used now to close cases.
731,000 matches of unsolved crimes were solved from 2001 to 2020
because of the advancements made. However, a disadvantage is that if
the DNA profile found as evidence is not on the National Database, the
offender cannot be convicted. This is a disadvantage as the offender will
, Harrison Naylor
be able to continue committing these crimes. For example, Robert
Napper, who committed multiple murders and rapes, was able to evade
the authorities as DNA found at the scenes did not match any on the
database as he had never been convicted of a crime before. This meant
he was able to continue committing crime. Another weakness is that
human error is a possibility. For example, cross contamination of evidence
can occur, meaning people can be wrongfully convicted for crimes they
did not commit, which is unjust. An example of this is the Randox Scandal.
The Randox Testing Services in Manchester (a private forensics lab) dealt
with toxicology and mostly drug driving tests for authorities in the UK.
Staff at the lab had manipulated results and over 10,000 criminal cases
were affected. This ruined people's lives, giving them criminal records and
even causing them to lose their job in some circumstances. A third
weakness is that people still get convicted of crimes that they did not
commit. An example of this is the David Butler case. The DNA sample
used to convict him was only a partial match and was poor quality, yet
was still used to convict him, which is unfair and is a weakness of
forensics in criminal investigations.
One type of case that forensics is useful in is sexual offences. This is
because the offender typically leaves behind biological evidence (blood,
skin cells, semen). This is analysed in laboratories and a swab from the
offender at the station will be taken to search for a match. It may also be
useful in murder cases. During the investigation, blood may be found if
there was some struggle, skin cells may be found under the victim's
fingernails, and the murder weapon may have the offenders DNA on. This
is also analysed in a lab, and a swab will be taken from the offender.
Furthermore, DNA is also useful when investigating burglaries. It can be
collected at the crime scene. Fingerprint analysis could also be used if it is
evident that the offender did not wear gloves. Regardless of this
usefulness, forensics may not be useful in other types of crime. For
example, it would not be useful when investigating a cybercrime as DNA is
not transferred online. This is a disadvantage as crimes like fraud can be
carried out online, where forensics cannot be used to convict the offender,
making it easier to evade authorities.
Interviews
Another technique used in criminal investigations is interviews. This
involves making a detailed account of an event from a person the police
believe to have knowledge that may be relevant to the case that they are
investigating. Eyewitness testimonies (EWT) are given by people who
spectated a crime. Most investigations rely on eyewitness testimonies to
understand how the event derived.
