AC1.2 ASSES THE USEFULNESS OF INVESTIGATIVE TECHNIQUES IN CRIMINAL
INVESTIGATIONS
DNA;
DNA profiling is one of the most reliable forms of evidence and can be collected through bodily fluids
like blood, skill cells, or hair follicles. The first advancement of DNA forensics was by Alec Jeffreys in
1985, which was developed to identify a killer that same year who had murdered two people.
DNA evidence is most useful at the investigation, trail, and identification part of a case, as not only
can it aid in identifying the victim/perpetrator, but it can also be used as evidence in court. To store
individuals DNA, the NDNAD (National DNA Database) was created, and it holds around 6.6 million
profiles (2020) from individuals that have been identified through saliva or hair. Another way to
identify an individual through DNA identification is fingerprint recognition, which was developed in
the 1990s, and it involves the process of collecting impressions that have been left by a person’s
finger ridges. They are usually found at impulsive crime scenes where the offence that took place
was improvised or non-premeditated as perpetrators who plan out their crimes typically wear
gloves. While there are specific DNA tests are typically effective since DNA is unique to one person. It
is helpful for crimes such as sexual assault – and rape -, homicide, assault, etc., or where the offence
involves physical presence of some kind. This means that DNA profiling may not be so effective for
white-collar crimes such as tax fraud or identity theft, as the offender is typically behind a
computer/device. According to statistics, DNA evidence can help identify the perpetrator around
60% of the time, and for cases where DNA technology had not been developed yet, the evidence
collected could help identify anyone who partook in the offence. Not only may it be able to identify
the offender, in cases such as murder, both the victim and the victim’s family can be identified as
DNA between family members is usually similar (this is also known as Familial DNA). Fingerprints are
also useful as there is an exceedingly small chance of you sharing a fingerprint with someone else,
and even though DNA evidence cannot be stored after the investigation has ceased, fingerprints can
be stored on the system and used later for comparisons.
However, on the UK’s national database, only 6.6 million individuals DNA is stored, and if a person’s
DNA is not on the system, then there is nothing to compare the evidence to. There are also huge
backlogs within the system, and there are cases of cross contamination occurring due to mishandling
of DNA. In addition, there are arguments to the ethical infringements of storing ones DNA. For the
limitations of fingerprints, getting a match can cost a lot of money and matched fingerprints do not
confirm or deny someone’s guilt; Fingerprints at the scene of the crime can be there for a multitude
of reasons such as the individual lives in proximity of the crime scene, or it is a public space. Anne
Marie Foy, mother of four, was murdered in September of 2005, and taxi driver David Butler’s DNA
was collected from the crime scene. Forensic collection of skin cells from Anne Marie Foy’s
fingernails had been matched with Butler’s DNA as his records were available on the NDNAB after he
willingly gave it when his mother’s house was burgled. It was later confirmed that Butler had a skin
condition that made him shed skin cells faster than the average individual, and the victim’s nails
were coated with nail polish, making them an attraction for DNA. The evidence was dropped, and
Butler was acquitted.
INTELLIGENCE DATABASES;
PNC:
The police have access to and can use the Police National computer (PNC) (which contains text
information that is relevant to their job) which was introduced in 2011. The PNC stores details of
around 12 million arrests/convictions, fingerprints, vehicle registration and information regarding
, those who have their licenses suspended while also holding profiles of people who are currently
wanted or missing. The PNC is available to all law enforcement agencies within England, Scotland,
Wales, Isle of Man, the Channel Islands, and Northern Island and it is used to help investigations for
both national and local police departments.
The PNC is able to help law enforcement agencies (such as the police or the UK criminal justice
system) have an easier time during critical investigations that may not have an ample amount of
time to investigate. The PNC provides real time checks on people, crimes, properties, and vehicles
while storing alerts for missing persons and vehicles that had been stolen. The PNC is effective
because of the amount of information on it that can be used during an investigation, and the PNC in
the UK has links to many other police databases in Europe which means there can be an extensive
share, especially if the case takes place over national waters within Europe. And by providing real
time checks, the police are able to quickly research the background of people within a short amount
of time.
However, the database if primarily in word format, meaning that the police have to heavily rely on
descriptions of people rather than photos. Descriptions of individuals are subjective, short brown
hair to one person may visualise completely different to another individual. Because of this basic
information, the police don’t have a lot to go off, and it could hinder the investigation rather than aid
it. Especially recently, the PNC (Police National Computer) is not really used as much anymore due to
the fact that the police often have to guess what a person looks like solely based off a description of
a suspect.
PND:
The Police National Database (or the PND) are available to all UK law enforcement agencies which
allows several organisations to share information and descriptions/photos of a suspect/individual.
However, the PND is completely separate to the Police National Computer. The PND contains over
3.5 billion records with nearly 20 million being added every month. The PND has around 222
databases with over 4000 users able to access the information on it.
This is incredibility useful as it allows forces across the world to share information to other forces
and agencies to make sure a case is solved as quickly and thoroughly as possible. The PND also
specialises in the safeguarding of minors and vulnerable individuals, terrorism counter, and
organised crime units such as drug rings, making it incredibility useful during cases that may involve
any of the things stated above. Not only does the database store actual criminal prosecutions and
records, it also stores allegations where a conviction may not have been given out or where the case
was dropped due to insufficient evidence (however this is not an exhaustive list). The billions of
records can help identify the criminals and prevent them too, making them effective during an
investigation.
However, much like the PNC, there are the disadvantages to using databases. One of the most
obvious about using technology is the risk for system malfunction, data leak, or hacking. If any of the
information on the Database is leaked (especially with the minors and the vulnerable individuals) it
can be a huge safeguarding issue with possible millions of confidential details being exposed to
society. This could increase crime and not be very helpful when being used during an investigation.
PROFILLING TECHNIQUES;
INVESTIGATIVE PROFILLING:
Investigative Psychology was developed from geographical profiling by psychologist David Canter
who stated that psychological profiling can aid the prosecution and the identification of the criminal
