Issues with forensic DNA profiling in India

So the lack of criminal DNA database is a big lacuna as far as India is concerned in the field of crime investigation. So in many blind cases of sexual assault, murder, burglary, etc., there are no leads available. A DNA profile of the perpetrator is available with the investigating agency after DNA profiling, but there is no suspect to compare. Searching for the perpetrator in such cases, like searching for a needle in a haystack and it leads to loss of time, and there is also resentment in the society. A lot of time and resources are invested to investigate the crime, and only in few cases perpetrator is identified. Many times the cases remain unsolved and are lost in oblivion with time.

If a criminal DNA database is available, which contains the DNA profiles of the convicted and repeat offenders, it becomes easy to search for the perpetrator. The other important issue with respect to DNA profiling is the issue pertaining to collection and preservation of sample for DNA profiling. So if the samples which have been collected for DNA profiling are not of good quality, then the results will never be good.

It is worth mentioning that collection and preservation of DNA evidence has remained an issue with the process of DNA profiling, and the success of the entire exercise depends on the sample collection and preservation, and there are certain wrong approaches and notions which are there in the society as well as the medical fraternity. So it is necessary that whatever is being sent for DNA profiling, it should be properly desiccated prior to packing. And it should be ensured that there is some amount of air circulation that keeps most of the moisture from the sample away, and there should be some desiccant also available along with the sample. Then we have the issues pertaining to quality management.

Quality assurance instils confidence in the mind of society. The concept of quality is visible even when a common article or a food item is purchased. A common man looks for the ISI mark or that mark. DNA evidence is the gold standard as far as identification from biological evidence is concerned. The technology is validated internationally and is very, very robust. However, there is lack of well documented and applied quality management system in the labs. To assure a certain degree of quality, a neutral third party assessment is must. This is obtained through accreditation.

There is also a lack of a society or a body where the experts can discuss the requirements of DNA profiling with respect to India and frame guidelines and set standards with respect to DNA profiling for for our nation. The next major issue is the issue pertaining to the use of statistics as far as the DNA forensics is concerned with respect to India. There is limited use of statistical interpretation in DNA forensics. Main reason it has been lack of population databases of allele frequencies. Efforts need to be made in the direction of carrying out population genetic studies on various population tribes of India to have a robust allele frequency data.

The studies can also identify markers that are more polymorphic with higher power of discrimination with respect to the Indian population. Therefore, DNA examiners must include statistical analysis in their reports to explain the weight of the DNA match. This is calculated using data published as part of population genetic studies. These studies ascertain the range of elements found at different loci in a given population set and the rate of occurrence. Also known as allelic frequency. Such studies are available for different groups of the Indian and South Asian population as well. Currently, though, there is limited research on population genetics data in India. And thus, unfortunately, most laboratories in India provide forensic DNA profiling reports without any statistical analysis.

In the absence of guidelines, the scientists often report the results simply as a match, which is scientifically inaccurate and highly misleading. In India, currently, forensic DNA profiling is predominantly used in cases of sexual violence and homicide, which often include DNA mixtures. While interpretation of DNA mixtures is inherently more difficult, it gets complicated in situations with small amounts of DNA or degraded samples. In such cases, reports simply identifying the accused as contributed to the crime sample without any statistical analysis is highly problematic. In fact, the practice of simply reporting a match is contrary to scientific principles and internationally set guidelines.

The National Research Council in the United States published a report in 1996 called the Evaluation of Forensic DNA Evidence, that it would not be scientifically justifiable to speak of a match as proof of identity in the absence of underlying data that permit some reasonable estimate of how rare the matching characteristics actually are. Therefore, to ensure scientific legitimacy, the use of statistical methods in laboratories should be made mandatory and scientists should report the results along with statistical analysis.

As a lawyer confronted with the evidence of DNA profiling in your case, you should think about three aspects. One, how probative is the DNA evidence in your case? What does the evidence of your client’s DNA establish for the prosecution’s case. The incriminating value of DNA evidence differs depending on the facts and circumstances of every case. There may be an explanation for finding a person’s DNA on a particular object or even on another person. For instance, in a case where a knife is found in the accused’s house and that is suspected to be the murder weapon, the presence of their DNA on it cannot be solely linked to the commission of the murder by the accused.

If the victim’s DNA is found on it, it may be relevant to probe whether there are circumstances other than the crime that may have led to the victim’s DNA to be found on it, such as, if the victim previously visited the house of the accused. Also, remember that the current DNA profiling methods cannot determine when the DNA was deposited. Two, has the chain of custody of the evidence been maintained to ensure its integrity. This includes both the crime scene samples and the reference samples that have been collected from the victim and the accused. From the information available on record, you should consider preparing a chart tracking the movement of all the evidence that has been sent for forensic examination.

This chart should contain information on the date of collection, storage, transfer of items to the lab or transfer between divisions of the lab, the condition in which they were sent to the lab and by who. And finally, the presence of seal on the items, which must be matched by the forensic laboratory with the specimen seal. There is often little information available about the storage of evidence by the police, and therefore it is crucial to do this exercise. Next, you should see how forensic DNA profiling was conducted in your case. Who conducted the examination process? Do they have special knowledge, professional experience or training in forensic DNA profiling?

You should also see what information did the examiner have access to and even the order of examination of evidence. It is important to note that the process of interpretation is subjective and that scientists are susceptible to cognitive bias. Studies have shown that knowing information which is irrelevant to forensic examination or knowing the reference DNA profile of an accused before interpreting the DNA profiles of the crime scene evidence may lead to bias. Next, is there sufficient information provided in the report about the individual steps involved in the process of DNA profiling?

Often, the DNA reports that are exhibited before courts do not contain any information about the method of extraction, amount of DNA extracted and amplified, or even a table of the alleles found on the different loci. The DNA report may also be submitted without accompanying electropherograms of the evidence and the reference samples, which are interpreted by the DNA examiner to arrive at their conclusion. Therefore, as a lawyer, you must check if you have access to all these materials, as they would be essential not only for a thorough examination of the DNA evidence in court, but also in case you wish to seek an opinion from an independent expert.

If you do not have access to these documents, then you should seek access either through the court or from the concerned laboratory. Finally, you may find that the results of DNA profiling have been reported without any statistical analysis. Please note that calculating a random match probability or likelihood ratio is the last step in the process of DNA profiling. Therefore, reporting of the DNA results without it makes the report incomplete. Currently, this aspect has been discussed by a few high courts in India, as well as in the 185th Law Commission report. However, submitting statistical analysis to determine the weight of DNA evidence in a case is yet to materialise as a forensic and legal practice in India.