• Forensic medicine academic and practitioner Dr. Ajith Tennakoon explained that once biological profiles (age, sex, stature) are established of human skeletal remains, members of the public have to provide very reliable info on suspected missing people, extrajudicial killings, etc.
• DNA profiling will follow with necessary tests and comparisons for the final identification

Investigating mass graves in Sri Lanka presents numerous legal, technical, and logistical challenges for forensic teams. However, the country has been able to conduct high-quality investigations into a number of mass graves with limited resources and time-consuming processes.

This was noted by the General John Kotelawala Defence University Medical Faculty's Forensic Medicine Unit Head Dr. Ajith Tennakoon, who also serves as a member of the Office on Missing Persons (OMP) and the National Authority on Assistance to and Protection of Victims of Crime. He is also a retired Chief Judicial Medical Officer (JMO) at the Institute of Forensic Medicine and Toxicology in Colombo and a past President of the College of Forensic Pathologists of Sri Lanka and the Medico Legal Society of Sri Lanka.

He added that with increased resources, more trained personnel, and faster legal processes, Sri Lanka can do better. He made these remarks during an interview with The Daily Morning. He emphasised on the importance of public support in investigating mass graves, especially when it comes to establishing the identities of the deceased. Without public support, he pointed out, the identification process could be seriously delayed.

Following are excerpts from the interview:

What constitutes a mass grave from a medico-legal standpoint? 

As medico-legal experts, we consider a mass grave to be a grave site where more than three dead bodies have been buried. It can be a burial site relating to enforced disappearances, extrajudicial killings, or disasters. During the tsunami, we had a similar situation. We did not have any law or any experience regarding handling dead bodies in disasters. Therefore, we had to go for mass burials. But, the situation is different now. We are ready to face any disaster, including natural and man-made ones.

When human skeletal remains are found, what government agencies get involved and what actions are taken?

When human skeletons are found, whether from a mass grave or as a single body, first of all, the local Police should be informed. The law enforcement agencies are the investigators. Then, the Police have to report the facts to the courts, or the relevant Magistrate, and the Magistrate will visit the site and order the Judicial Medical Officer (JMO) to investigate it. Then, the medico-legal investigation will commence. After that, a lot of other agencies join the process. In the case of a mass grave, the Archaeology Department also joins because excavations should be done in a scientific manner. At the same time, supporting analysts like the Government Analyst’s (GA) Department also join. From the JMO's side, we have a separate sub-specialisation called forensic anthropology – that is the investigation and examination into human remains, or bones. These are the agencies that directly get involved in the examination of mass graves, from the point of discovery to the point of reporting and giving evidence at the court.

In addition to skeletons, what other objects are collected?

In addition to human skeletons, there are other objects which we call artefacts. These artefacts are very important to establish the time period of the incident and also to determine the circumstance of the relevant deaths, e.g. whether they were caused by killings or some natural disasters. For example, if you find a bullet, some sort of a weapon, a private object like a piece of jewellery, or something like handcuffs, we can determine the circumstances of the relevant death and it helps identify the individual. We collect all these things during our investigations into mass graves.

How is evidence collected, stored, and preserved? How does tagging and documentation take place?

The collection or recovery of bones and other evidence is very important. We have to prove where this evidence or the bones were found. Therefore, we have to do very accurate, appropriate photography and recording. Then, when we get the photographs and the recordings, we use a number, a tag number, because we have to have a register. According to our tag numbers, we have to show where it was. Where the dead bodies and artefacts are found, these are very important for later scientific analysis. Therefore, when we collect them, we have to tag them, number them, photograph them, record them, and document them properly, so that you can analyse them with the overall evidence that we collect from the bones as well as from the crime scene. Video recording is also done. In fact, sometimes, we use drones to get aerial photographs and official photographs. Official photography and recording are compulsory.

We hear a lot about carbon dating tests when it comes to investigations on mass graves. What are the other commonly performed tests?

Actually, carbon dating is the last option, because it is more appropriate for very ancient situations. Carbon dating is important to find out the time that the incident has happened. But, it is not for recent incidents, it is more suitable for incidents that happened at least about 50 years ago. When it comes to more recent cases, carbon dating is not important.

There are other tests that we do. There are archaeological tests, because we go layer by layer (in soil). These tests can be done to determine how old a particular (soil) layer is. Then, when it comes to bones, we perform deoxyribonucleic acid (DNA) profiling and DNA extraction from the bones. Especially in human remains, we use teeth to identify the person through these methods. Sometimes, we conduct toxicology analysis if we suspect that some form of poisoning has taken place. Depending on the situation, we can apply some other tests also. However, it is mainly the DNA test, DNA profiling, and the toxicology tests that we conduct in cases of mass graves.

If we find some artefacts like bullets, in such cases, we can get the services of forensic ballistic experts to find out what sort of weapon has been used to fire the bullet. If there is a suspected weapon, we can definitely compare it with the evidence (bullet) to determine whether the bullet has been shot by that particular weapon.

What steps are taken to confirm the identity of a deceased person?

When we discover human remains, we don’t receive it in the form of a dead body. Only the bones are remaining. Therefore, we have to collect old bones from that human body, wash them, clean them, examine them, and then lay them out properly. There is a way that bones are joined together from the skull to the feet. We have to lay them down and examine them, and that is usually a forensic anthropologist’s work. Then, through the examination of these bones, we have to establish something called a biological profile. That contains mainly the age, the sex and stature, and also the cause and manner of death later. We have various methods to determine age, sex and stature. One difference is that in some countries, racial identification is also carried out to determine whether the deceased was of African, Asian or European descent. But, in Sri Lanka, we are all Asian. Therefore, we generally don’t go for racial identification. We cannot ethnically categorise them as they are all the same.

After that, we pay attention to individual identification. If you suspect that a person’s body could be lying in a certain place, in such cases, we can do the extraction of the DNA from the discovered bones. We then have to get a DNA extraction, or profiling, from an immediate family member. This usually happens to be the mother or a sibling, as they are the best living people with whose DNA the deceased’s DNA can be compared with. We get the DNA profiling from them and then compare it in order to establish the identity of the deceased person.

Can you describe in simple terms the steps taken to determine the cause and manner of death?

The next step in this process is to establish the cause and manner of death. In a fresh dead body, we would see injuries in the flesh. However, when it comes to old human remains, or bones, there are no such things. Therefore, we look for any bony injuries such as fractures, which we call anti-mortem injuries which means before death. Peri-mortem injuries are also taken into account, and it refers to injuries during the process of death. The way that we differentiate them is, when it comes to anti-mortem injuries, there can be a healing process, although there could be no healing process when injuries occur during death. There is another category called post-mortem, that refers to after death. When these bones are lying on the soil, there can be animal attacks or various degradative processes. So, there can be post-mortem injuries as well. We have to examine and identify these injuries. Then, if we can see peri-mortem injuries caused by, for example firearms, a blast or blunt force trauma, we can find out the cause of death. Depending on the place of these injuries, sometimes, we can definitely say that the death cannot be an accident or self-inflicted. So, in such cases, we can say that the deaths have been caused by violence and we can exclude an accidental nature or self-infliction. Likewise, we identify the cause and the circumstances of death with these injuries in the bones as well as artefacts or other important evidence that we find in the grave site.

What are the key challenges faced in this process?

First of all, this process has to go through the relevant legal process because it is a crime. There has to be a Magistrate’s order and Police involvement. This process takes some time and there are delays. Investigations and other related steps also sometimes get delayed. For example, we send samples to the GA and especially the extraction of DNA from bones is very complicated. For example, I once sent a sample and I got the report after about three years. So, when there are a lot of samples, there will be problems. We may also have to get the support from the private sector as well as foreign, international support. Then, we finally sent the report to the court.

In addition, at times, there are also legal challenges and technical problems, the latter due to a lack of trained personnel. In fact, we recently did a training program for archaeologists because the registered archaeologists in the Archaeology Department did not have forensic archaeology training. We trained them through the OMP and the International Committee of the Red Cross (ICRC) so that we can get their support in the future. Training Police personnel is another problem that we are facing. 

Sometimes, we need certain latest technologies such as ground-penetrating laser instruments to find any bones under the soil rather than excavating. We can use these technologies to check whether there are any collections of bones, or human remains, under the soil. 

When collecting and presenting evidence, what are the commonly-faced challenges?

When collecting evidence, we have to work as a team with archaeologists, anthropologists under the JMO, and Scene of Crime Officers (SOCO). We cannot just go and do it and we cannot use machinery. We have to go layer by layer using special instruments to prevent any damage to bone fragments. Those processes are challenging, because they are very time consuming. We may also have to stay in the site for months. Logistics should be supported and funding has to come, usually from the Justice Ministry. The OMP operates under the Justice Ministry. 

Sometimes, preserving samples is challenging. We have to collect them in separate boxes and keep them until we finish the investigations. Usually, we keep them in JMO's offices. However, not all JMO offices can keep them. In Colombo, we have a separate department on forensic anthropology. In Jaffna, we have a trained anthropologist attached to the Jaffna University and the JMO's office. However, such is not available in other places. So, storing and ensuring the safety of these specimens is a concern. We have to do everything to prevent any alterations as well. 

What is the legal situation concerning these processes, especially when conducting tests?

In Sri Lanka, it is mainly the Code of Criminal Procedure which discusses investigations into suspected grave sites and also crimes including murders. The OMP (Establishment, Administration and Discharge of Functions) Act also discusses the role of the OMP in investigating suspected mass graves. The legal situation is such that it always has to be reported to a Magistrate, and the Magistrate has to order other stakeholders to investigate. After that, it goes as a teamwork and the Magistrate also gets involved.

How is the general public’s support sought in these processes, especially to identify victims?

This is very important. The biological profile establishes age, sex and stature, and then, we have to go for the final identification of the person. For that, we have to get information from the public about missing people, or who are supposed to have been subjected to an extrajudicial killing or similar incidents. The people have to come up with information about who are suspected to have been buried in a particular mass grave. At the moment, we have about 14 mass graves under investigation in this country. However, all these 14 have been discovered sort of accidentally, for example, while constructing various buildings. The only mass grave that we got information about as a complaint has not been investigated yet, and that is located in Kurukkalmadam, Kalawanchikudi, in the Batticaloa Magistrate’s Court area. All the other 14 were found accidentally. When we find human remains and do the biological profiles, we cannot identify the person only through that. For that, we have to have very reliable information from the public whether they believe that their loved ones could be there. Then only we can take their DNA and do the necessary tests and comparisons for the final identification. We cannot do mass DNA profiling of all the bones that we find as that will be a very expensive process. In this process, we need public support.