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'DNA experts could also be guilty of giving false results'

by Pallavi Polanki  Oct 11, 2012 09:45 IST

#DNA   #forensic evidence   #Q&A  

In an in-depth interview to Firstpost, GV Rao, DNA analyst and former chief staff scientist at the Hyderabad-based Centre For DNA Fingerprinting and Diagnostics discussed of critical issues facing the DNA testing in India, the problems with the DNA profiling Bill, and his experience as an expert witness in some of the most sensational cases that have dominated headlines in the last two decades.

Excerpts from the interview:

Has the use of DNA tests in crime investigations become more prevalent in India in recent times? Could you give us a perspective on the use of DNA fingerprinting technology to solve crimes in India today?

Very much. Between the years 1987 to 1996, DNA testing was being done in Hyderabad only. However post–1996, DNA testing facilities have opened up in Chennai, Delhi, Chandigarh, Kolkata, Gujarat, Madhya Pradesh, etc. We have been using it for regular paternity, offences on women etc.

However, today we are very much behind the rest of the world in upgradation of technology as required. You are well aware that recently a Delhi sessions court set aside a DNA report as being the outcome of outdated technology.
The high court of Gujarat too commented that “DNA results cannot be treated as conclusive proof and cannot be made use of as sole basis of conviction in a criminal case, more so when the Random Occurrence Ratio is not available of Indian Society”.

Further, the backlog of cases is quite large in each of the DNA labs in India, and not much is being done about it. We have still not obtained or adopted the DNA techniques to identify difficult samples. Recently, in the Bhanwari Devi case, the CBI had to send the victim’s bones to the FBI, USA, for identification. This is a sad reflection of the present status of DNA technology in India.

Representational image. Reuters

Does India have the necessary expertise and infrastructure to competently gather, investigate and analyse DNA evidence for forensic purposes?

It is the man behind the machine which makes for the expertise and not the machine in front of the man. We have the machines but the men are missing. We are spending crores of rupees on infrastructure for housing DNA labs without hiring/recruiting fresh talent. Regular paternity cases are not very difficult but the test of expertise comes when it comes to difficult samples like identification of victims of mass disasters, burnt bodies, skeletal remains from unmarked graves etc. This is where Indian DNA labs are failing.

The senior serologists of forensic labs are now designated as DNA experts without exposing them to international standards involved in reporting DNA cases. We need to have a dedicated DNA unit with advanced infrastructure and knowledgeable experts under the National Disaster Management Unit to handle difficult forensic case.

Is police force in India adequately trained to collect DNA samples from the crime scene? Do you recall cases where poor quality of DNA samples compromised the investigation?

Not at all. In India there are no special crime case investigators. We have a law and order police station for each area and from bandobast duty to control crowds. It is a tall order expecting them to collect samples. In some states there are special teams which collect samples for DNA testing and then hand it over to the police.

Maintaining very high levels of sterile conditions is a prerequisite for collection of samples for DNA testing. Further, selecting the correct tissues from the dead body during post-mortem or from a scene of crime is one major problem. Furthermore, selecting locally available preservatives for controlling further damage to the biological material so collected is another problem during field collections. Till date none of the DNA labs have made any sample collection kits made available to police stations or other agencies. A major problem of contamination comes from the DNA of the persons collecting the samples.

In the Beant Singh assassination case, the local doctors of the mortuary without due attention stored the assassin’s sample in Formalin (which is poison for DNA) and we had to develop a new method to clean the DNA and arrive at the conclusion.

Is the technology being responsibly used to solve crimes? What are some of the major problems/flaws you observe?

Without sounding very pessimistic let me assertively say that DNA testing in India is being used very irresponsibly. The very fundamental of DNA testing is applying population biostatistics to arrive at a conclusion and this very fundamental is given a goodbye by the Indian DNA labs. Few labs say that they are applying biostatistics but then their reliance is on a very small sample size. I have been emphasizing since 2001 that major populations should be DNA profiled and a huge database be created for using it to report DNA cases

Even today judiciary is not too much aware as to what goes into DNA testing and what the standards to be followed are. Defense advocates too are not that well informed to bring out what the DNA report is lacking. Yes, DNA testing gives conclusive results, if done, as per scientific standards. However, in my experience, I have observed that we could also be guilty of giving false positive results and sending innocents behind bars.

Other major flaws are lack of standards, guidelines, accreditation, proficiency testing of the DNA labs and its experts. Each DNA lab is again following different procedures for conducting the test. No proper records of the tests conducted are being maintained for production in a court of law for its inspection. DNA experts are not being tested for their proficiency in their expertise by a third party and presently they are getting away with such minimal expertise.

In accredited and validated labs of US and Europe, lot of emphasis is laid on chain of custody of DNA samples. This means that every movement of the DNA sample from collection to final outcome of the result is documented. This chain of custody document is very crucial to show how the DNA sample was handled and by whom. This particular aspect is not being practiced in Indian DNA labs. Therefore, it is necessary that strong directions from an expert committee should come forth for implementing chain of custody in all DNA labs of India.

Could you tell us about your experience as an expert witness in cases that have relied on DNA evidence? What are some of the high profile cases in India where the technology has been used?

I joined the Centre for DNA Fingerprinting and Diagnostics (CDFD) in 1996 on adhoc basis and advanced to Chief Staff Scientist, DNA Fingerprinting Laboratory in 1997 and continued at the Centre till 2009.

I have reported as DNA expert witness in around 1000 DNA cases and deposed around 200 times as a DNA expert in mostly criminal cases. A few of the sensational cases where my DNA expertise was relied upon by the judiciary as evidence include the Naina Sahni or the Tandoor case, Priyadarshini Mattoo, Black Buck killing case, Swami Premananda, Chattisinghpora  False encounter Case (Jammu & Kashmir) and Beant Singh assassination case.

DNA evidence played a very crucial role in the Mattoo case. The DNA from seminal discharge of the accused found on the undergarments of the victim and her private parts were compared with the DNA of the accused and they matched conclusively. This established two things. Firstly, it connected the crime scene with the accused. Secondly, it established that the accused was responsible for committing rape on the victim. As the defense could not find holes in the DNA evidence, the accused got convicted for the crime he committed.

In the Premananda case, a pregnant girl reported to the police that the accused Premananda was responsible for her pregnancy. This was denied by the accused. This was in 1995. The victim sought abortion and we suggested that the foetus along with the blood samples of the victim and accused be sent for DNA Test. DNA of the foetus, the victim and the accused were compared with each other and it was found that the product of conception or foetus was the result of accused Premananda committing rape on the victim resulting in pregnancy. The principle of DNA testing is that a child or growing foetus is composed of 50% each of DNA it receives from the biological father and mother. Once this DNA of the child matches with that of DNA patterns of the biological parents, it is said to be the biological child with due probability drawn from population database.

In the Beant Singh case, the difficult samples had to be analysed by inventing a new DNA isolation method to identify the assassin. In Salman Khan case, a whole new technique was again developed to identify black buck at a species level.

The most satisfying case of all was the Chattisinghpora False encounter Case of J&K. Satisfying because I could report that victims samples were swapped to protect some vested interests. I was under pressure not to reveal it but as DNA does not bend to fear or favor, I went ahead and reported. This lead to widespread protests and government of J&K had to concede and allow me to collect the samples from the graves independently and only then the truth came out. This case also attracted Supreme Court’s condemnation.

The government has drafted a DNA profiling bill. Will this legislation help bring the necessary standardization, quality control and regulation of the application of the technology for forensic purposes? Does it violate the privacy of citizens?

Unfortunately, this Bill does not provide for standardization, quality control and regulation except for collection of DNA samples of everybody involved in all civil and criminal cases, including suspects. The funny part of the bill is that it will also cover people who undergo abortion, paternity suits and receive or donate organs.

The provisions of the Bill are not fool-proof and it shall affect the genetic privacy of Indians whose data will be under Government control indefinitely on a DNA database. With rise in human rights violation in India this information would be a threat to privacy and rights of every Indian, so DNA profiled. The courts of Europe and the US have ruled these actions of storing of DNA samples as unlawful and breach of privacy and strangely we are venturing at this late hour to bring in an Act for collection of DNA samples.

This Bill is not of any use for what is really required for Indian DNA labs. We need standards, protocols, guidelines, amendments to IPC and CrPC for effective implementation of DNA testing. In short, what we need is an expert committee to address these issues and the rest will fall in place.

This Bill does not provide for any provision for creation of population databases for use in DNA test result reporting. The statement within the Bill that the data will be used for creation of population statistics for the purpose of identification, research, protocol development or quality control is not substantiated with how it will be achieved.

In my view, DNA Profiling Bill is inappropriate and does not suit any purpose except for waste of public exchequer

Is the creation of a DNA database, as the bill proposes, make sense/practical for a country the size of India?

A sudden decision to create DNA databases is not practical. We have over 2000 ethnic groups or populations in our country and creation of database for populations of such a big size is nothing but another UIDAI disaster in the making. So we should realize that we have missed the bus and we need to change the DNA reporting style from saying “that Mr X is the father of the child Y” to “that Mr X may be the father of the child Y”. To reach conclusively, Courts need to rely on DNA testing along with other evidences.

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