You may have heard, in the last day or two, about the ‘DNA Bill’ being approved in Parliament. This is a really exciting step forward for science and for the reach of law in South Africa. This post will look into the history and effectiveness of DNA profiling, and what in means in this country.
Firstly, let’s look at what exactly we are talking about. The generally accepted approach is to take a DNA sample from a criminal or suspect, and record a number of unique markers, called loci. I once heard Vanessa Lynch, founder of The DNA Project, compare the process to paging through a number of books and recording the letters at a number of specific positions in each book. You could identify the book if those letters were linked to the book in a database, but on their own, those letters mean nothing. This allows an accurate and reliable identification of the individual, without a record of any potentially discriminatory DNA data. This information, known as a DNA profile, is then put into a database, along with the profiles of any police or laboratory personnel that may have come into contact with the samples.
Various countries around the world have implemented DNA profile databases – a 2008 Interpol report (PDF) states that 54 countries have a national database. The most comprehensive databases are in the USA and the UK, unsurprisingly. The only major difference between these various databases is their inclusiveness, which is where the delays around implementation in SA have arisen. Inclusiveness refers to which DNA profiles can be kept in the database. One of the most inclusive databases is the National DNA Database (NDNAD) in the UK, where any suspect’s DNA profile may be stored indefinitely. In the USA, this is illegal – any DNA profile of a person not convicted of a crime must be expunged from the database and the sample must be destroyed after a certain time. The inclusiveness of the NDNAD has caused some civil rights groups to object to storing the DNA profile of innocent people, claiming an infringement of the right to privacy.
So, the DNA Bill, or rather the Criminal Law (Forensic Procedures) Amendment Bill. This has been in the pipeline for around five years – the infrastructure has been in place for some time, but civil rights concerns over privacy and potential for exploitation by corrupt officials have kept it in the planning stages. The bill authorises the establishment and maintenance of a database with profiles from both convicted criminals and suspects (the samples themselves will be destroyed).
While implementation has been raised as a very real concern, this has to be seen as a great step forward for our country. The most obvious benefit is an improvement in conviction rates – DNA evidence is a very compelling argument for conviction in court. Then we come to the more nebulous benefits, such as decreasing criminal activity. Hard and fast numbers are hard to come by, but this study (PDF) shows a very real decrease in crime as a result of DNA databasing, especially in crimes where evidence is left behind, such as assault, theft and murder.
An interesting point in all of this is the role of DNA databases in getting early offenders on the database. Criminals, on the whole, do not wake up one day and decide to murder someone – rather, they may start with robbery, then assault, then eventually move on to murder. If their DNA profile is stored after the first offence, conviction for the second or third offence will be that much easier.
While it may be some time before we see the benefits of this Bill on our daily lives, it is surely an exciting step for science in South Africa. If nothing else, it will provide graduate scientists with a few more job opportunities.