It is not clear whether the background odour of the legitimately buried does disguise the smell of the clandestinely interred. We still do not know a lot about how the volatile organic compounds (VOCs) that create the smell, permeate the soil and become airborne, react to different soil conditions and other environmental factors such as air temperature and humidity. A body and its associated microbial community give off hundreds of VOCs, the most well-known of these being putrescene, cadaverine, skatole and indole.
At low concentrations skatole and indole have a pleasant flowery odour and the synthetic version of skatole is used to manufacture some perfumes as a substitute for civet or combined with sandalwood. It can also be used to flavour food such as ice cream and may be added to cigarettes. For those keen on gardening, every time you breathe in the heady scent of jasmine or orange blossom you breathe in skatole. Many insect groups are attracted to skatole, particularly flies, beetles and male euglossine bees, also known as orchid bees. The plants produce skatole as a means of attracting these pollinators. The hope that a legitimately buried body, six-foot deep and contained in a casket, is sufficient to disguise the odour of a body much closer to the surface is probably optimistic; nevertheless, people try.
Cadaver dogs, like people, are fallible. Several years ago, I was working on a case where we were looking for the remains of a woman who was believed to have been murdered by her boyfriend and buried in a park near their home. After several hours of examining the park with Sophie and locating areas of interest, it was decided that the search could be made more efficient by using cadaver dogs. Each dog is only allowed to work for a limited amount of time before they become tired or distracted, so they were brought out on rotation to ensure our time was used most efficiently.
Satisfyingly, the cadaver dogs responded strongly to several of the areas that Sophie and I thought most promising. There remained a degree of doubt, so after some discussion it was decided that the most promising locations should be probed with an auger. Essentially, an auger is a corkscrew that is a foot or two in length. It is driven into the ground to release more VOCs and thus make detection by the cadaver dogs more likely. This form of probing is controversial because it is not entirely clear that the auger has the desired effect, since much of the volatility of the compounds appears to be dependent upon environmental conditions such as temperature and humidity. More importantly, there is a significant risk that evidence, or the remains of the person being searched for, could be damaged by the auger. Unsurprisingly, Sophie was not a fan of this course of action, and strenuously advised against it. Being part of a criminal investigation requires considerable patience and diplomacy. Quite often decisions are made elsewhere, and it is necessary to accept these decisions and proceed as best you can, something both Sophie and I find quite hard at times. We are not diplomats.
Reluctantly, we acknowledged the decision to proceed with the auger. Assidulously, we noted the discussion’s contents, our viewpoint and the outcome. After all the locations had been augered, we waited half an hour for the gases to rise from the newly exposed soil. Another of the dogs was brought out. The dog reacted strongly at one of the sites, and we agreed to proceed with excavation. Up until that point, we had been informally examining the area, but it was now decided to declare a potential crime scene. Declaring an area as a potential crime scene elevates the level of attention to detail and documentation. A cordon is set up and only those of us needed to work directly on the scene are allowed within. Naturally, full protective clothing is worn.
Most of us who work in forensics share a pet hate about crime-scene dramas, the regularity with which the un-besuited lead investigator character saunters under the perimeter barrier and into the tent protecting the remains of the murder victim. Sometimes, they’ll even stoop and pick something up, often with a pen! There is no way this would happen in a well-managed crime scene. The crime-scene manager would eviscerate the offender. For a start, no matter who you are, you have to declare your identity and log in; the officer on duty at the perimeter will insist upon that. And, before you approach the deposition scene, you’ll be expected to don a protective suit.
Those white disposable, all encompassing, rustling romper suits serve a very important purpose. They protect a crime scene from contamination from other sources. To a certain extent, they also protect the wearer. When I’m putting on a protective suit I feel a mixture of being rather important and slightly ridiculous. The suits are rather taxing to wear. Your hearing becomes muffled so you spend quite a bit of time trying not to say ‘what?’ or ‘pardon, I can’t hear you?’. This is exacerbated by the constant rustling of the fabric. Because I wear glasses when I’m working, my glasses get steamed up by my breath that is redirected by the face mask. In winter, the extra layer can be quite a blessing, especially if it’s windy. In summer, the suits are purgatory – clamminess abounds.
We were now working on a potential crime scene, so we spent quite a bit of time documenting the location in more detail with photographs, sketch maps and copious notes recording our activities. Sophie started to scrape away the soil surface with her small hand trowel. All the soil needs to be moved to one side and carefully checked for potential evidence. Very quickly she found the edges of a previously dug hole, known as a ‘pit’, approximately 40 cm by 30 cm. I have worked very closely with forensic archaeologists and anthropologists when they’ve excavated a pit, and I am always amazed by their ability to detect the difference between undisturbed soil and soil that has been dug but is now heavily compacted. Their wrists are ultrasensitive, and each movement of the trowel defines the edge of the pit without damaging it. Quite often I will need to excavate roots, and I have attempted to emulate this action; it is quite an art.
After half an hour or so, a small pink piece of towelling came into view. Even for experienced detectives, crime scene managers and other members of the team, this is a tense and emotionally draining time. There is a degree of controlled excitation in the air; as professionals, we all hope to find the victim and as ordinary, caring people there is trepidation. It’s not nice to be able to confirm that someone has been murdered, because there is always a hope that they have simply gone missing. The smallness of the pit and gradually revealed dimensions of the towel bundle led us to consider the likelihood that the victim had been dismembered.
From all perspectives, dismembered remains are far more challenging than an entire body. An investigating team will have to locate every part of the person’s remains, which can be time consuming and extremely hard to accomplish. This is especially true if more than one location is involved. Human remains damaged by dismemberment are also more complex to interpret, as damage to bones and tissue may have arisen at the time of death or afterwards. Quite often human remains are damaged by animals such as rats or foxes. Understanding how this damage occurred is often essential in understanding a case. And, of course, it is very hard for the living to bear the news about what befell their loved one before their death.
As more of the towel became visible, we could also see strands of blonde hair emerging from the edge of the bundle. There was a quick scramble to verify the colour of the hair of the victim prior to her disappearance. No one was quite sure. Sophie was now finally ready to lift the bundle from the pit and start the process of unwrapping. At this point, we were all feeling extremely tense. As the towelling was gently pulled back, we all felt a draining wave of disappointment. Within the bundle lay a small dog. There was a realisation that we had failed and, rather comically, that we had just spent several hours digging up someone’s pet dog.
Sadly, we were unable to return the dog to the grave. The dog’s remains had to be taken away and destroyed. We could not reinter the remains because the park was quite a crime hotspot and leaving the dog in place could have caused problems and wasted resources for future investigations. Sophie had two final tasks to do before we proceeded. First, she ensured there was nothing buried beneath the dog’s remains, so she continued excavating u
ntil the base of the pit was reached. Nothing was found. This needed to be done because there have been cases of criminals burying human remains beneath animal bodies or under legitimate burials. Sophie also had to make detailed notes of the excavation. This may seem unwarranted but even negative results must be accounted for. There is always the possibility that we made an error and missed vital evidence (or the victim). Documenting our activities is key to demonstrating that the work was undertaken to the best of our abilities. As this tale demonstrates, even experts and cadaver dogs are fallible. But we all learn from these occasions.
*
Several years ago, I was suffering from some self-doubt about my ability to do forensic casework. One of the more challenging things about what I do is that, in many respects, I’m never in familiar territory. Each case is very different. Not only are the awful things that people do to each other varied but the circumstances under which they occur are always unique. This scenario is amplified when the casework is outside of the built environment. This is simply because the natural world is very complex. The landscape and the plants that I work with are nearly always different in some way or another. This can lead to moments of uncertainty when approaching a new scene. I found myself feeling that there was an expectation that I was arriving, fully prepared and capable of resolving the burning issue that the investigating team needed investigating. And sometimes that led me to feel less than qualified to do the job. As is often the case, these sort of emotions are born of a degree of insecurity, because it can be very challenging to be surrounded by very experienced people, especially at a crime scene! Sophie very kindly and effectively told me that I was wrong to feel that way. She pointed out that most detectives will work on a serious crime involving landscape and plants only once or twice in their careers. Most serious crime happens in the built environment and most murder victims are found within a few days of their death at most. By the time that I was having my wobble in self-confidence, I had worked on around twenty serious crime cases of this nature, so, relatively speaking I was an old hand! As I have become more experienced, these feeling have waned, but I am careful to not allow them to be replaced by hubris. By degrees, over the last few years I have started to feel the odd wince when I experience something that I don’t feel is best practice. Part of the problem for most police forces and, to a lesser extent, some forensic service providers, is that because of the relative rarity of these sort of cases they are not always geared up to deal with them.
It came as quite a shock to me that many churchyards in England and Wales do not have accurate information on where the burials in their grounds are. This is not entirely surprising for those that are hundreds of years old but, for more recent burials, it is. In typical British style, the requirements concerning burial grounds are a patchwork of national law, Church of England tradition, local authority rules and the best practice of the many other secular and religious bodies. Ordinarily, only local authorities are required to maintain maps of burial grounds. This seems to me to be rather extraordinary and deeply unhelpful for those of us working on a criminal investigation.
Several years ago, a ‘cold case’, the murder of a teenager who was believed to have been killed by a paedophile, was reactivated following credible information from new witnesses being given to the police. One of the main search areas was a local church. The burial ground of this church was several hundred years old and apart from the very recent burials, the church authorities were unable to provide the police with any accurate information concerning late-twentieth-century burials. As a consequence, the police had to assume that the whole burial ground was a potential location for the teenager’s remains.
The police and the specialist forensics company they were working with requested that I assist in locating the victim’s remains. Vegetation can be a useful tool in helping locate murder victims in such cases, but there are limitations. Often, signs of disturbance diminish and are lost after two to five years. This case was approximately thirty years old. On top of that, graveyards are usually quite actively maintained and there is a lot of continuous activity. People visit loved ones and plant flowers or small shrubs on their graves. Maintenance staff mow lawns and prune trees and shrubs. And, if the grounds are still in use, burials occur. All of this leads to a very complex patchwork of human activity and it can be very hard to identify signs of illegal activity. I spent a rather despondent day hoping to find signs that may be helpful. I was unsuccessful. As far as I know, the victim has still not been recovered and their family remains in ghastly limbo.
As part of another case, I spent three days walking back and forth across a very large Victorian-era local authority cemetery. I was assisting the police in looking for a person who had been tortured and murdered by a criminal gang. It was believed that the victim had been killed within the last six months. Those few days were tiring. It was mid-summer, absolutely boiling hot and incredibly time-consuming work. Map in hand, I examined over 10,000 graves looking for signs of disturbance. If the victim was in the cemetery, there was a reasonable likelihood that they would be found. Most of the graves were marked by simple headstones. For these graves I looked for signs of damage to the turf or movement of gravel-chip dressings on the surface of the grave. Each time I noted anything of interest it would be documented on my copy of the cemetery burial maps.
A small minority of the graves were grander and either consisted of single, large stone slabs or more elaborate chest tombs. Chest tombs are sometimes favoured by criminals because, depending upon the weight, the covering slab can be slid to one side and replaced once the contraband or victim has been placed within. One of the tasks for the search team was to examine these tombs for signs of disturbance. More obvious signs such as recent breakages of the slabs or scratch marks made by tools such as crowbars were also marked up on our maps. And I applied some of my curious botanical wizardry by looking at damage done to the plants.
Ivy (Hedera spp.) is one of our most abundant and ecologically important wild and cultivated plants. It is also immensely valuable as a nectar source for a wide range of invertebrates. Ivy often abounds in graveyards, covering the ground, tree trunks and stone memorials. By our standards, ivy is a very odd plant. It is the only wild plant of these islands that is strongly dimorphic in growth, meaning that ivy grows in two distinct and different stages. The juvenile stage is made up of long, slender, sinuous stems that are normally pressed closely to the surface upon which they grow. These stems have short, fine roots along one side of the stem. These roots are normally firmly attached to whatever they touch and help the plant climb. The adult stage lacks this sinuous growth and is more bushy, akin to an ordinary shrub. This stage bears branches with flowers and ultimately, fruit. Flowering ivy is one of the best food sources for a very wide range of insects; let it bloom!
The juvenile ivy stems are the most useful to me. It is impossible to move an ivy-clad grave slab without either breaking the stems or detaching them. Even if an attempt were made to reposition the slab carefully, I would see the tell-tale signs. To us natural historians, it is well known that old graveyards are havens for wildlife and that tombstones are often particularly good habitats. They can harbour a rich community of mosses, liverworts and lichens, as well as larger plants such as ferns or the delightfully fleshy navelwort (Umbillicus rupestris). These intricate communities also host a diverse assemblage of minute animals such as tardigrades, also known as ‘little water bears’.
Not all gravestones are excellent habitats. Heavily polished marble and slate surfaces offer little in the way of a home, except for bacteria. Generally, rough-hewn limestone and granite rock offer the best range of niches on which life can take told. Most lichens, mosses and liverworts start life as small, relatively simple spores, which are most frequently spread in the environment by water or air. In most cases, each spore is less than a hundredth of a millimetre across. Most never make it to maturity; they are either killed by viruses or eaten by predators such as the voracious tard
igrades. Many are zapped by the ultraviolet radiation of the sun or are desiccated.
If a spore survives and starts to grow, it will simultaneously spread in all directions across the surface, gradually getting larger. As each year and decade progresses the organism will gradually increase in size and usually develop a roughly circular outline, the youngest part on the outer edge and the oldest in the middle. In particularly old individuals the centre starts to die, and a ring will form. Very often these growth patches will form on the edge of one grave slab and grow over onto the adjoining surface, locking the vault closed with a biological seal. As with the ivy, it is not possible to slide the top of a chest tomb to one side without breaking that seal. The colony will be torn apart and it is very unlikely that the corresponding portions will align true if the top is slid back into place.
After a couple of days of mind-aching pacing back and forth, my maps were dotted with about thirty graves that I thought showed some signs of disturbance. My observations were cross-referenced with those made by the police search team and my forensic anthropology colleague. We then prioritised the most likely locations. The first grave we examined was a large Victorian chest tomb. It had quite a few indicators that made us feel we might be successful: there were recent scratch marks on the limestone, some of the ivy and adjoining vegetation was damaged and some of the concentric circles of lichen growth on adjoining slabs were broken up and no longer aligned. All of this was carefully documented.
Murder Most Florid Page 9
