Traces

by Patricia Wiltshire

  I am not frightened of dead bodies. To me, corpses have ceased to be people; they are repositories of information where nature has left clues that we might follow. Very few times in my career have I let my guard down and been affected by the cadavers in the mortuary. The first was a 22-year-old prostitute found dead in a wood, leaving three children behind. I was deeply sad for that girl because of all she had suffered. She had been rejected by her parents at 16 and forced to make her own way. She became insidiously controlled by a pimp who purposefully made her addicted to cocaine and then put her to work to support him and her drug habit. She bore three children, not knowing the identity of any of the fathers, but she would not give them up and her scrawny, scruffy little body bore testament to its neglect as she serviced men so that she could keep her children and cope with the rest of her existence. I cried over that girl as she lay exposed and cold on the stainless steel surface of the mortuary table, not because she was dead, but for all the struggle and misery she had suffered in her pathetic existence, while keeping steadfast in her loyalty to her children. I so admired her for that.

  One of the other cases that moved me was that of the murder of a 15-year-old Scandinavian girl, so completely perfect as she lay there on the slab, naked in the harsh lights of the mortuary. She was killed in woodland on a lovely summer’s day because of a man’s frantic lust and his obsession with seeing her naked as he was kneeling in the grass masturbating. Her physical perfection moved me to deep sadness – for the life she might have had, should have had, but never would.

  I have often stared at death – not only the deaths of those whose stories I have tried to piece back together, but also the deaths of my own loved ones. I lost my parents, as we all do, but, before that, and sooner than I was prepared for, I lost the grandmother who half-raised me; and, when I was still young myself, I was there when my daughter, not yet two years old, slipped away. My fanciful mind still sees her as a little girl in a Margaret Tarrant children’s picture book – where the whole of life is portrayed as being sunny and perfect. But my pragmatic self understands my fantasy. I have been close to death myself, and I see it for what it is: oblivious and dispassionate, just another one of nature’s many processes, as unfathomable as any of the rest.

  Consider this book as a journey through the world I work in, and me your tour guide into that fascinating edge-land where nature and death are intertwined. Along the way, I will take you to the hedgerow in Hertfordshire where my eyes were first opened to the potentialities of plants playing a role in criminal investigation – a moment that transformed my academic view of the natural world, and the new possibilities contained within it.

  I have sat at crime scenes for hours with maggot-ridden corpses; and been to the place known as the ‘body farm’ in Tennessee, where cadavers are laid out to rot so that we might learn from them. We will go to the apartment in Dundee where blood-soaked carpets and cushions, thick with grey and brown growths of mould, provided vital evidence to identify the time of a murder victim’s death. We will go through dense plantations of trees and across lonely moorland; to a body left on an urban roundabout; and then to shamanistic rituals, harnessing the hallucinogenic properties of toxic plants, in the heart of southern England; so, on to the shallow graves of too many girls who went missing, never to be seen by their loved ones again. Along the way I will lead you on forays into my own history: my loves, my losses, and the narrow, little valley in Wales where I was awakened to the wonders and breadth of the natural world. If, come the end, I have left you with a little bit of the wonder I find in looking at plants, animals, and microbes, and perhaps with a new appreciation of how we, as human beings, operate within nature, not set apart from it, then I will consider my work a success.

  The fact of the matter is that too few of us really understand how interconnected we are with the natural world. The vast majority of us now live in towns and suburbs but, whether we live in cities, or whether we live in the remote reaches of the country, nature is everywhere. We might be the most interfering species ever to have walked or crawled on this planet, but we share it with more than a quarter of a million species of plants, 35,000 species of mammal, bird, fish, and amphibian and, at the best current estimates, around 3 million species of fungus, and perhaps as many as 30 million different species of insect. And all of this without even mentioning the myriads of unknown microscopic species on which so much forensic ecology relies. There might be 7 billion of us on this planet, but for every one of us there are more than 200 million insects. When you think of it like this, it is perhaps no surprise to learn that nature is marking us in every step we take.

  Nowadays it is fashionable to say that we live in a surveillance society, but your movements can be tracked by more than cameras. I can tell the kind of place you have been by the microscopic particles on your shoes. I can see which route you walked home, through bluebell woodland or across a garden, by the pollen on your shoes. I might tell you where you lingered with a loved one, which corner of a field you waited in, which wall you leaned on when you were waiting for your friend. And if you are one of those unlucky souls who comes to me as a cadaver, by measuring the moulds growing on your skin and clothes, and by the pollen and spores in your hair, clothing, and shoes, I might tell your loved ones how, where, and when you died. I can tell you who took your loved one away by the pollen embedded into his boots as he carried her off to put her in a shallow grave. By retrieving pollen, spores, and other particles from the membranes lining their nasal cavities, I can tell you if someone was buried alive, or snorted up the surface of the grave as they were being strangled. Nature leaves her clues all over us, outside and within. We all leave our marks on the environment, but the environment leaves its marks on us too, and, although she sometimes needs to be coaxed, nature will invariably give up her secrets to those of us who know where to look.

  2.

  SEARCHING AND FINDING

  There was a girl who went missing. In the world we live in, there are too many stories that begin like this, but one in particular lodges in my mind. Joanne Nelson vanished on Valentine’s Day in 2005. By all accounts, she was bright and vivacious. She lived in Hull, East Yorkshire, and had dreams of travelling the world. She had strawberry blonde hair, cut in a bob with a fringe just above the line of her eyes, and her colleagues at the local Jobcentre had no idea where she might have gone. As far as her parents knew, her boyfriend idolised her.

  Of course, I knew nothing of this. The first thing I knew about the Valentine Girl was when, already missing for 11 days, the police rang and asked me to help find her.

  This is often how it begins for me: the unexpected call that draws me out of bed and on to the motorway to travel anywhere the police are waiting at a crime scene. Sometimes I will be up at dawn, standing over a ditch, or in a lonely motorway lay-by, looking over a body and taking samples from its remains, or, when a call comes in, I might be in my study at home, surrounded by books, papers, journals, and reference materials, with my cat on my lap, and my microscopes in the room next door, ready for action. Other times I will be in the laboratory or listening to a lecture at some scientific meeting. Familiar questions hit me one after another: Can you help us? What can you tell us, Pat? What can you show? Often the police have a limited understanding of what I can do, and what I need to be able to capture the traces nature has left behind, to build up a picture of the possibilities – the might-have-been and the probably was.

  This time, all the police knew for certain was that Joanne Nelson was dead. She had died 11 days previously, strangled by the hands of her lover. Her killer thought he had been wily enough and clever enough to fool the world. He appeared on camera, pleading for his girlfriend’s return. He gave interviews to the press and stood alongside her unknowing parents, summoning up tears. But his tears were for his own plight and not Joanne’s.

  Murderers can be vain and arrogant; they often return to the sites of their killings. People say this is wickedness, driving them back to the
murder scene to gloat – but perhaps they go back just to check on their handiwork, or perhaps they are compulsively drawn back to what they have done. But Joanne’s murderer had no need to go back to the scene of the crime because it happened in his own home. He had strangled her in the kitchen of the house they shared, overpowering her easily after she nagged him over household chores. He had had enough; fury welled up in him and he lost his temper. When a crime happens in the home, the avenues for a forensic detective to explore are often limited. Homes are full of our fingerprints and DNA and they will be coated in fibres left behind by our clothing. Joanne’s house had been scoured and nothing much had been found but, thankfully, the truth had already come out.

  For a time, Joanne’s boyfriend had kept up the façade of innocence. He told the world she had run away. He made plaintive pleas for her to return to the family home. But the secret was too terrible to keep and, when he confided in a friend, and that friend confided in his mother, the truth came out. Paul Dyson confessed to the killing he had earlier denied. The police had their man, but there was a problem. There was no body.

  Dyson could drive, but he had never gained a licence. He only vaguely knew the roads of Hull, and beyond that, one road was much the same as any other. On the night he murdered Joanne, he wrapped her body in plastic and drove her as far as he could from familiar territory. He drove furtively through the night, along unfamiliar country lanes, until he found a lonely spot where he could bury her. Now, over a week later, he could recall so little of where he had been that it might have been anywhere in Yorkshire that needed less than half a tank of petrol to get there. The area I had to consider was vast.

  ‘What can you do for us, Pat?’ the policeman asked me. And my question to him was the same as it always is: ‘Well, what exactly are you asking, and what exhibits have you got so that I can try to give you answers?’

  My work often begins with things that you might think mundane, and so it was here, when the police provided me with the killer’s jeans, a pair of Nike trainers, a pair of Reeboks, and a garden fork found at his parents’ home. Paul Dyson had disposed of Joanne’s body in her own Vauxhall Estate, and this meant that evidence in the form of pollen grains, spores, or other microscopic palynomorphs could be retrieved from the vehicle. I asked for the car’s nearside and offside footwell mats, both rubber pedal covers, the mat from the boot, and the front spoiler from the bodywork. Exhibits such as these are my stock in trade: the shoes worn when a lover carried away his or her partner to bury the body; the material in which a still-warm corpse was wrapped; his trousers and jacket. These have been dutifully taken, logged, recorded, and sealed in evidence bags by crime scene officers.

  ‘What can you get from things like these?’ you might ask, and many policemen still do. On one level, the answer is straightforward. Edmond Locard, the French criminologist and pioneer of the forensic sciences, who lived from 1877–1966, is associated with the maxim ‘every contact leaves a trace’, and this has become enshrined in forensic lore as ‘Locard’s exchange principle’. This clearly impressed Sir Arthur Conan Doyle who once visited him in Lyon. What Locard postulated was that every time a criminal enters a crime scene, he both brings something with him that he leaves there, and takes something of the crime scene away with him. Both these can be used as what we call ‘trace evidence’ – whether that is DNA, fingerprints, hairs, fibres – or the pollen and spores around which my own work is centred. They help us establish contact between people, objects, and places, and, on occasion, provide a context for the time.

  On another level, though, a case like Joanne Nelson’s captures perfectly how the role of the forensic ecologist diverges from other forensic work, such as DNA analysis. I might be looking to retrieve trace evidence from the exhibits I have been given, but that is only the precursor to the main event because what I am really searching for is an image. An image of a place that is half-imagined and half-real. What I am doing is absorbing all the information I can and using it to paint a mental picture of a place that I have never visited, and quite possibly never will. I call the image the ‘picture of place’ – an imagined construct, but out there somewhere. This picture represents something real, a place I can summon into being by carefully considering the pollen, spores, and other microscopic matter that I retrieve from exhibits. It is the place I can see on the backs of my eyelids whenever I close my eyes. Some parts of the image are sharp, others are murky, sliding around like amoebae as more information is gleaned from the microscope. The place where you buried your lover; the place where your victim says you pinned her down and raped her, and which you say you were never near. It’s the place where you picked up the tell-tale clues that will one day expose you, and it is how nature relays the stories that nothing else can.

  And so, two pairs of trainers, the foot pedals of the car, and a garden fork. These were the objects that might yield a picture of the place where poor Joanne Nelson lay.

  My job is to give answers, or intelligence that might lead to those answers. It is work that can be long, tedious, and tiresome. For long hours I will sit hunched over my microscope before I stand up and stretch, wandering around and allowing my neck to rest. I might go straight back to the microscope because I had found something interesting and wanted to press on, or I might take a walk in the garden with my cat, or even play the piano which stands against the wall in my study. The concentration it takes is heavy, and must be sustained for long periods. Remaining focused matters more than anything else as, without this, any hope of correctly visualising the picture of a place can vanish.

  Hours can pass by. I have driven myself to exhaustion trying to decide whether the elements in a spine on a pollen grain are straight or oblique, whether the faint pattern of swirls are more characteristic of hawthorn, or some other member of the rose family. It is on decisions like this that cases can succeed or fail; a person’s freedom might rest upon the difference between one identification and the next.

  As I scan and count the various grains, I am building up images of plants and, from them, the habitats in which they have been growing. When an assemblage of pollen types eventually emerges from the microscope slides, it gives an idea of the vegetation at and around the crime scene; and from this I get clues as to the acidity and wetness of the soil, whether the place is well-lit or shady, and whether it is woodland and, if so, what kind. It might take me hours. It might take days or weeks, or longer. But sometimes, it all comes together neatly and, when this happens, the feeling of satisfaction is unparalleled. It can be like placing the last pieces into a jigsaw puzzle although, of course, there may be some wrong pieces and some gaps in my made-up picture. There may be pollen grains from other places on the shoes, and some of the plants at the crime scene may not be represented, but this is not a major worry because, if there are enough right puzzle pieces, the picture will be recognisable.

  Joanne Nelson’s murder was one of those rare cases where the picture emerged quickly and clearly; a few scans with the microscope and the essence of the picture was there. I did not have to think very carefully. They were wisps of evidence, but wisps that were almost tangible. Paul Dyson might not have known where he had been on the night he disposed of Joanne Nelson’s body, but his belongings were leading the way.

  I soon became certain that Joanne was lying in, or close to, commercial woodland; but I have learnt, over the years, that one piece of a puzzle is barely ever enough. You must look closer and dig a little deeper. Nor is the material you collect from a crime scene ever perfectly pristine and clear. Pollen might have disappeared or become degraded. There will be other microscopic plant and animal structures: remains of micro-fungi, algae, plant, and animal fragments; all these may litter and confuse the view from which I am trying to pick out the critical evidence. And identifying the pollen grains is only the start. A bluebell woodland in Surrey might be similar to a bluebell woodland in Essex; Forestry Commission plantations exist all over the country, and similar collections of trees may be p
lanted in all of them. Worse still, in a single sample, a lone pine might yield a similar result to that of the edge of an extensive pine woodland. No, what you want – what you need – is to build up a picture, with all its contrasting and contradictory hues. Like a perfume, it might have one overriding scent but be suffused with others that can help narrow down the area we must search. That overriding scent might put you on heather moorland, in a pine forest, or somewhere along the coast, but the moors are vast, wild places, plantation forests extend for miles across our nation and, in Britain, we are never so very far away from the sea. No, what you are seeking is a combination, a specific mix of trace evidence, that can make your crime scene unique.

  Now, holding the picture of place in my mind, I stretched to pick up the telephone. It was answered immediately, and I was relieved to hear the calm voice of the kindly Detective Superintendent, Ray Higgins. His assistant officers had been frantic for information, buzzing like drones around a queen bee, but Ray was different. His gentle manner belied his keen competence, sharp intellect, and steely determination to find this little girl for her parents.

  ‘Pat?’

  I was thankful that we were not using Skype; as I continued talking with my eyes closed, I must have looked like some demented mystic. ‘Yes, Ray, I can see the kind of place she lies in.’

  I could sense the relief at the other end of the line. ‘She is in a Forestry Commission-type plantation.’ Ray became animated.

  ‘Pat – he said there were Christmas trees there. That makes sense.’

  There were a few grains of spruce in the profile; spruce, the tree doomed to be sacrificed each winter festival. I was pretty sure that it was not a plantation devoted just to the Christmas market though, because only young trees are chosen for that. To produce pollen, a spruce tree must be sexually mature, about 40 years old at least, and it would be very tall by that age. If Dyson had recognised Christmas trees, there may have been a considerable stand of them, possibly near the entrance to the woodland. It is an enigma that one finds so little spruce pollen right in the middle of a pure spruce woodland, or even near one, although, to the initiated, the answer is obvious. Foresters favour spruce trees at about the age of 40 for felling, just as they are coming to sexual maturity; they are cut down in their prime, leaving very little pollen evidence of their former eminence in the landscape. If you do find spruce pollen, there must have been mature trees somewhere in the area.