Unit 3 1.2 miss johannes
Assess the usefulness of investigative techniques in criminal investigations.
The crime scene:
● The police are usually the first to the scene to set up a cordon (prevents people from
entering a crime scene). They approach the scene on
stepping plates.
● CSI then documents and processes the scene.
● Police officers also used to prevent people from entering
the crime scene.
● Any police detective entering the scene would be
required to wear a protective suit.
● Tents can also be set up to provide a distinct barrier as
well as a screen.
● Crime scene tape creates an inner cordon.
● Evidence markers are used to document evidence.
Investigative techniques
Intelligence databases
This refers to info that has been obtained by many sources, including confidential sources, and
has been recorded and evaluated. This info may be stored in a variety of databases that police
officers can access such as:
The police national computer - contains several separate databases.
● It stores details of over 12 million peoples arrests, convictions and police cautions, with
links to biometric databases for fingerprints and the national DNA database.
● Vehicle registration data and info on 48 million people who hold a driving license, and on
those who are disqualified.
● The pnc also holds info on missing and wanted persons.
The police national database- contains intelligence about suspected criminal activity as well
as data on the pnc. It holds over 3.5 billion searchable records and is made up of 220 linked
databases.
, Crimint and the gangs matrix- crimint holds info on criminals, suspects and protestors and
the gangs matrix holds info on suspected gang members.
International databases- uk police can also access databases that share info between police
forces in different countries. These include the INTERPOL databases on child secual
exploitation,biometric records (DNA+ fingerprints), stolen property e.g stolen art work, firearms
and organised crime networks.
Forensics
Refers to the scientific techniques and tests that are used to assist in investigating crime.
Forensics have had a massive progression in the last 100 years. Forensic evidence can include
biological materials (e.g blood,semen, skin flakes and hair) along with fingerprints, shoe prints,
weapons, fibres and threads from clothing, paint flakes etc.
It is essential that access to the crime scene is strictly controlled and that investigators wear
appropriate protective clothing in order to avoid contaminating evidence. Once collected, the
evidence can then be examined by forensic specialists who then share their information with the
police to aid an investigation.
DNA evidence
DNA evidence is the area in which forensics has made the greatest progress. DNA is found in
almost every cell of the body, and each person's DNA profile is different (except for identical
twins). In recent years, highly sensitive techniques have been developed for the extraction and
rapid analysis of minute quantities of DNA samples. This has made DNA profiling the most
important development in solving serious crime since fingerprinting was invented.
The first ever use of forensic DNA profiling: ( case study)
● DNA profiling was invented by the scientist, Alec Jeffreys in 1958 and it was first used to
investigate the rape and murder of two girls in leicstershire in 1983 and 1986.
● Using the new technique, Jeffreys established that the semen left in both cases
belonged to the same man. Police then took samples of
all 4,583 men in the area and eventually found a match
with Colin Pitchfork, who was convicted of both murders.
● The test also exonerated Robert Buckland, a 17 yr old
with learning difficulties who had admitted to the 1983
killing. Buckland became the first person to ever be
cleared of a crime using DNA analysis.
● however , Pitchfork was only caught when a co worker
revealed to workmates that he had taken the blood test
masquerading as Pitchfork, because Pitchfork told him he
had already given a sample while pretending to be a
friend who wanted to avoid being harassed by police
because of a previous conviction.
Assess the usefulness of investigative techniques in criminal investigations.
The crime scene:
● The police are usually the first to the scene to set up a cordon (prevents people from
entering a crime scene). They approach the scene on
stepping plates.
● CSI then documents and processes the scene.
● Police officers also used to prevent people from entering
the crime scene.
● Any police detective entering the scene would be
required to wear a protective suit.
● Tents can also be set up to provide a distinct barrier as
well as a screen.
● Crime scene tape creates an inner cordon.
● Evidence markers are used to document evidence.
Investigative techniques
Intelligence databases
This refers to info that has been obtained by many sources, including confidential sources, and
has been recorded and evaluated. This info may be stored in a variety of databases that police
officers can access such as:
The police national computer - contains several separate databases.
● It stores details of over 12 million peoples arrests, convictions and police cautions, with
links to biometric databases for fingerprints and the national DNA database.
● Vehicle registration data and info on 48 million people who hold a driving license, and on
those who are disqualified.
● The pnc also holds info on missing and wanted persons.
The police national database- contains intelligence about suspected criminal activity as well
as data on the pnc. It holds over 3.5 billion searchable records and is made up of 220 linked
databases.
, Crimint and the gangs matrix- crimint holds info on criminals, suspects and protestors and
the gangs matrix holds info on suspected gang members.
International databases- uk police can also access databases that share info between police
forces in different countries. These include the INTERPOL databases on child secual
exploitation,biometric records (DNA+ fingerprints), stolen property e.g stolen art work, firearms
and organised crime networks.
Forensics
Refers to the scientific techniques and tests that are used to assist in investigating crime.
Forensics have had a massive progression in the last 100 years. Forensic evidence can include
biological materials (e.g blood,semen, skin flakes and hair) along with fingerprints, shoe prints,
weapons, fibres and threads from clothing, paint flakes etc.
It is essential that access to the crime scene is strictly controlled and that investigators wear
appropriate protective clothing in order to avoid contaminating evidence. Once collected, the
evidence can then be examined by forensic specialists who then share their information with the
police to aid an investigation.
DNA evidence
DNA evidence is the area in which forensics has made the greatest progress. DNA is found in
almost every cell of the body, and each person's DNA profile is different (except for identical
twins). In recent years, highly sensitive techniques have been developed for the extraction and
rapid analysis of minute quantities of DNA samples. This has made DNA profiling the most
important development in solving serious crime since fingerprinting was invented.
The first ever use of forensic DNA profiling: ( case study)
● DNA profiling was invented by the scientist, Alec Jeffreys in 1958 and it was first used to
investigate the rape and murder of two girls in leicstershire in 1983 and 1986.
● Using the new technique, Jeffreys established that the semen left in both cases
belonged to the same man. Police then took samples of
all 4,583 men in the area and eventually found a match
with Colin Pitchfork, who was convicted of both murders.
● The test also exonerated Robert Buckland, a 17 yr old
with learning difficulties who had admitted to the 1983
killing. Buckland became the first person to ever be
cleared of a crime using DNA analysis.
● however , Pitchfork was only caught when a co worker
revealed to workmates that he had taken the blood test
masquerading as Pitchfork, because Pitchfork told him he
had already given a sample while pretending to be a
friend who wanted to avoid being harassed by police
because of a previous conviction.
