DNA: The crime-fighting tool that needs to be used

This article was featured in The Witness, 3 Sep 2010 on Page 9.

DNA: The crime-fighting tool that needs to be used
03 Sep 2010

Dr Carolyn Hancock, a Director of The DNA Project

EARLIER this year Rudi Venter, who had been charged with the murder of his wife, walked out of court a free man. DNA evidence had determined he was innocent.

Venter’s wife was beaten to death with a baseball bat at their Johannesburg home in 2006. At the time, Venter said he had returned home after taking his children to school and seen two men running from the house before finding his critically injured wife. Venter was arrested for her murder a year later. Just before he was due to go to trial in February, his legal team asked an expert to interpret the DNA results from material found at the scene. It was found that DNA samples obtained at the scene contained the blood of Venter’s wife and two unidentified men. Venter’s blood was not present anywhere. Consequently, the state withdrew the murder charge.

If the DNA found at the scene had been processed at the time as a matter of routine, Venter would not have spent four years with a murder charge hanging over him.

“DNA does not only prove guilt, but it can also prove innocence,” says Dr Carolyn Hancock, a director of the DNA Project and a former genetics lecturer at the University of KwaZulu-Natal.

“In the United States, 258 people have been freed from prison on the basis of DNA results. The average time they had spent in prison was 13 years. Seventeen of them were on death row for crimes they never committed.”

Currently, this cannot happen in South Africa as the processing of DNA for forensic purposes by the South African Police Force Forensic Science Laboratory is prioritised according to five categories. Top of the list is a request from prosecutors when they have a suspect. The laboratory then undertakes to do a complete DNA analysis within 120 days or by trial date.

Bottom of the list are those cases with no known suspect. “This is what we believe should change,” says Hancock. “With a DNA database, reoffenders would immediately be identified.”

For this to happen, aspects of the Criminal Procedure Act of 1977 need to be amended in order for the country’s police force to be able to routinely use DNA for forensic purposes. The act is out of date; back in 1977, nobody had started using DNA for forensic purposes and consequently the act doesn’t specifically regulate the use of DNA for criminal intelligence purposes.

To address this omission, the Criminal Law Forensic Procedures Amendment Bill was drafted in 2008. It deals with the use of DNA and looks to allow police access to fingerprint databases other than their own, such as those of the departments of home affairs and transport, which routinely take fingerprints for identification purposes.

The draft bill was subsequently divided into two parts — one dealing with fingerprints, the other with DNA. The fingerprint legislation has been adopted. As a result, in addition to about five million fingerprints recorded by the SAPF, the police will now be allowed to search the other databases and access around 33 million fingerprints.

The DNA part of the bill is on hold while the parliamentary portfolio committee overseeing the bill reviews presentations regarding the issue and travels overseas to see how DNA analysis is done in other countries. It is unlikely that any decision will be made on the bill until next year.

If the bill is passed, which seems likely, capacity issues will have to be addressed if it is to be implemented effectively. One solution, given the lack of capacity of the SAPF, would be to outsource work to private laboratories.

“The capacity does exist out there to make this work,” says Hancock. “The immediate demand could be met. The use of private labs for the analysis of reference samples taken from arrestees would be a short-term solution, but they are used everywhere else and it is regarded as international best practice.”

But there remains a need for more qualified personnel within the SAPF and to that end, Hancock, as part of an initiative funded by the sponsors of the DNA Project, has been instrumental in developing a post-graduate qualification in forensic DNA analysis so that the state will have access to well-qualified personnel. This degree is already being offered at the University of the Free State and will be offered next year at the University of Cape Town. “The course material is freely available to any South African post-graduate institution,” she says.

Although the draft bill might be on hold, the DNA Project is promoting and publicising the use of DNA analysis in the fight against crime. The DNA Project is a non-profit, public-benefit organisation lobbying for the expansion of a national DNA database and it proposes that DNA profiles be created from DNA samples collected from crime scenes and from all those suspected or convicted of a crime.

“In this country, such a database would be hugely beneficial because of the number of criminals who reoffend,” says Hancock. “If you get them on the database the first time they commit an offence, then if you don’t convict them for their first offence you will hopefully do so when they reoffend.”

The DNA Project has just launched a new campaign aimed at promoting DNA awareness in South Africa. “We are primarily targeting community police forums and security companies,” says Hancock.

“The latter are often the first on a crime scene. You press a panic button and they are the first to respond. We want to ensure that anyone who is first at a crime scene ensures that any DNA evidence is preserved as it can easily be contaminated or destroyed. This evidence should be collected by trained SAPF crime-scene investigators.”

This nation-wide campaign sees the DNA Project offering free DNA awareness workshops to educate people as to the benefits of utilising DNA evidence for crime detection and prevention, and the need to contain and not contaminate a crime scene. “We would like to offer these workshops, which are free of charge, to those who are likely to be the first to arrive at a crime scene. For example, first responding officers, security guards, police reservists and paramedics.”

The DNA project is hoping to get this message to 10 000 people this year and they also have government funding to reach as many schoolchildren as possible. “Genetics is part of the school curriculum,” says Hancock, “and forensics is something they study — and many of them watch CSI on TV.”

The workshops will provide a basic understanding of how DNA profiling can be used to assist in criminal investigations in South Africa and the importance of preserving DNA evidence which may be at a crime scene. “This is essential as no matter how good our legislation or our laboratories are”, says Hancock, “we need to have the evidence properly preserved and collected at the crime scene.”

FORENSIC DNA evidence plays a vital role in criminal investigations because it can identify and help convict a suspect who is guilty of committing a crime or prove the innocence of a suspect who has been wrongly accused of a crime.


DNA stands for deoxyribonucleic acid. This is the name for the chemical which is found in almost every cell in the human body and which is the blueprint or recipe for that person’s characteristics. Everyone’s DNA is unique (unless they have an identical twin). A person’s DNA is also exactly the same in every cell of their body. For example, the DNA pattern, also known as the DNA profile, in a human’s blood is the same as the DNA in his or her skin cells, body tissue, semen and saliva, which makes it possible to compare crime-scene evidence such as semen stains, saliva on cigarette butts and blood on clothing, with DNA obtained from a blood sample or cheek scraping taken from a suspect.


A DNA profile is simply a unique list of letters and numbers obtained from a person’s DNA that acts as a personal identifier. A DNA profile contains no information about a person’s physical characteristics, their mental predisposition or anything about their medical his-tory. In the same way as fingerprints link a suspect to a crime, DNA provides scientific evidence that can identify or exclude a suspect from a police investigation. It can also be used to identify a victim through DNA from relatives, even when a body cannot be found. DNA profiling can also link two or more crime scenes. When evidence from one crime scene is compared with evidence from another, the police can tell whether it was the same person who had committed two different crimes. Even very old cases, which the police thought would never be solved, may contain DNA evidence that can be used to identify the person who committed that crime.


Once DNA samples have been collected from a crime scene and processed at the Forensic Science Laboratory, the DNA profile, which is the identification number taken from the DNA sample, can be compared with the DNA profiles taken from a known suspect. If no known suspect exists, the DNA profile taken from the crime scene is still valuable, as when it is entered onto the national DNA database, the police can see whether that DNA profile links to another known DNA profile on the DNA database or perhaps it may even link several different crimes to each other.

— DNA Project.


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