What are the advantages of the use of DNA in criminal cases?

The use of DNA in Society

Since the discovery of DNA it has been a concept which has revolutionised much of society as we see it today. For example medical areas such as paternity testing and genetics have improved markedly since the notion of DNA has been introduced. In relation to a paternity test now all is required is a small swab of the inside of a potential fathers cheek with the DNA gained able to be compared against that of the child.

The use of DNA in the Criminal Justice System

DNA has also revolutionised the field of criminology and made a huge impact in the functioning of the Criminal Justice System in a much improved manner.

What are the advantages of using DNA in the Criminal Justice System?

The main advantages of the use of DNA in the Criminal Justice System can be broken down into the following three categories:

  1. The use of DNA to solve crimes

  2. Identifying victims of crime

  3. Linking two crimes

The use of DNA to solve crimes

Since the advent of DNA profiling, DNA has been used as evidence and has become an extremely powerful tool in the arena of the criminal law. Often the DNA of an individual may be found on the body of their victim or at the scene of the crime and can be adequately used to pinpoint that individual as the perpetrator.

Evidence that is resistant to tampering

Due to the fact that an individual’s DNA is the same in all areas of their body it cannot be altered or changed in any way meaning that it is effectively a form of evidence which is resistant to any form of tampering.

DNA is different between all individuals

No DNA is the same between two individual people – unless those individuals are identical twins – this means that the evidence can be relied upon as an accurate way to direct or to conclude criminal cases. Most often the use of DNA at a crime scene will enable investigators to move the case in the right direction and to remove potential suspects from the investigation. This will then enable the police to concentrate their manpower directly on the case rather than wasting time interviewing potential suspects – for this reason alone the use of DNA has a huge advantage in criminal cases.

Identifying Victims of Crime

Another important function of DNA in criminal cases is that it enables the victims of crime to be identified. In some cases where the condition of the body when discovered has left the victim unidentifiable hair and many other parts of the body can provide viable DNA evidence which can be analysed and profiled to identify the victim of the crime.

Linking Two Crimes

If the same DNA is found at two different crime scenes then it can be used to link together the crimes enabling criminal investigators to determine if a serial criminal is at large or even to establish if the victims knew one another.

The National DNA Database

What is the National DNA Database?

DNA samples which have been obtained for analysis from the collection of DNA at crime scenes and from samples taken from individuals in police custody can be held in a national database called the National DNA Database.

The UK National DNA Database

The UK’s National DNA Database is the largest database of any country with 5.2% of the UK population being on the database. Over the last five years there has been a continued expansion of the DNA database with currently over 3.4 million DNA profiles being held on the database – this accounts for the majority of the population of known active offenders.

DNA Database Top Government Priority

Maintaining and developing the DNA Database is one of the UK Government’s top priorities. In fact government and police investment into the database has topped £300million over the last five years.

Are there any plans to create a voluntary database?

Despite the use of DNA being such an important issue there currently are no plans from the UK Government to introduce a voluntary database or a universal compulsory database which would see the entire population required to provide DNA to be included in the database.

What will be the process when the police find a DNA match from the database?

Upon receipt of a DNA match report from the National DNA Database the police will proceed to arrest the suspect. However, charges cannot be brought upon a DNA profile match alone as there must always be appropriate supporting evidence.

What happens once the charges are brought?

What the process will be once the charges are brought depends upon the plea by the defendant:

  • If there is a clear indication of a guilty plea, following consultation with the Crown Prosecution Service (CPS) it may be possible to proceed without the need for any further statements of scientific DNA work.

  • If there is no indication of a guilty plea but the DNA evidence is not in issue the CPS may decide to proceed on the basis of the National DNA Database match report.

  • If there is no indication of a guilty plea or in fact no plea at all and the DNA evidence is an issue in the case then an abbreviated statement will be requested from the crime stain supplier before the Plea and Case Management Hearing.

  • If there is an indication of a not guilty plea and the DNA evidence is an issue then a full evaluative statement concerning the DNA findings must be supplied – the full evaluative statement must make reference to any additional Police and Criminal Evidence (PACE) and Criminal Justice (CJ) sample analysis that may have been undertaken. It must also address the issues in the case as identified by the parties.