Another common leak is that of semen. So, it is never safe for the pathologist to assume, on finding semen outside the body, that the deceased had sex just before he died – although he might have done. And, just because gastric contents are found in the mouth, there can be no assumption that vomiting was a cause of death, since regurgitation is found in about 25 per cent of post-mortems.
The police officers really did not need reminding that death can be a messy business. They knew that bodies often leak from orifices in a way their owners would find shameful in life. In fact, I long ago understood, after talking to people about their end-of-life fears, that this undignified leakage is something many find worrying about death. But I believe there is no need for anxiety. Those of us who choose to work with the dead are non-judgemental and respectful and I feel that worriers really won’t care about this when life is actually draining away from them. I think they will be entirely involved in the process of letting go and giving up their bodies. Embarrassment is just the kind of worldly concern which I believe the dying relinquish, often perhaps with relief.
The next process after death is cooling. I could have devoted an entire lecture to this subject but I offered only the most general of guidelines: I wanted the police officers to recognize how unrealistic TV movies are about judging the time of death accurately from a body’s temperature. The next process is the stiffening of the muscles known as rigor mortis: they were familiar with that one. Then I showed pictures of hypostasis.
On death, blood stops circulating and its components, cells and protein, become subject to the normal laws of gravity. Which means that the red blood cells sink and settle in the lowest areas of the body. The tiny blood vessels in the skin in those areas then become distended by blood. This makes the skin initially appear pink but within five or six hours it turns a very angry colour, bright pink with a bluish tinge. And here is the paint box we call hypostasis.
Its alarming appearance is heightened, in Caucasians, by the great whiteness of adjacent parts of the body, those which are pressed against a firm surface – a bed or the floor perhaps – where the blood vessels are squashed flat and so cannot fill. These areas stay blanched. A Caucasian who dies lying in bed therefore has hypostasis staining most of the skin on the back, as well as the back of the neck, thighs and lower legs – and very white skin on the buttocks as well as white patches over the shoulders. In darker-skinned people, hypostasis is, of course, still present, but its appearance is much less livid.
Hypostasis does eventually disappear. But only when the blood is dispersed by the final process after death. This process is decomposition. Many people find the idea of decomposition repellent. It might help to remember that this is an important natural process that completes the life cycle of the human body and returns it to the chemical pool that is the earth. It is hard to imagine what our world would be like without the ultimately cleansing process of decomposition, smelly and ugly though it may seem to the living.
There are three ways a body can decompose: by putrefaction, mummification or adipocere, of which putrefaction is by far the most common.
I had brought pictures and the officers seemed unaffected by those I had shown so far. But I watched them sit up now, hoping, I guessed, they wouldn’t have to look at putrefaction. But a putrefying body is simply one in which the soft tissues are turning slowly to liquid. The speed of this process of course depends on temperature. In the UK, bodies will usually start to putrefy around three or four days after death and this will be visible to the naked eye quickly. I showed a picture of a body and, with the pointer, drew the officers’ attention to one small area of green discolouration just on the right side of the lower abdomen.
‘It’s usually just there,’ I said. ‘That’s where you’ll first see putrefaction.’
Our guts are full of bacteria, which are vital for digestion. Now, in death, those bacteria break out of the bowel and into the abdominal cavity and then the blood vessels. The process starts at this certain point on the abdomen, near the appendix, because the abdominal wall is very close to the intestine here. Putrefaction can begin elsewhere, but only with good reason: for example, if a body is lying across a heating pipe, or part of it is in direct sunlight. Wherever it begins, by the time the green blotch is visible on the skin, then the bacteria are running riot inside the body.
The blood vessels provide easy channels for the bacteria to spread, causing the haemoglobin there to decompose. Visible result: the extraordinary and beautiful fern-like pattern of the veins closest to the surface becomes clearly etched on the skin as though tattooed in brown. It is often evident on the arms and thighs.
I think the police officers were beginning to realize now that this was no David Attenborough documentary. But, like every death process, this rather beautiful stage is temporary. Gradually the pattern is lost as the skin blisters into red and brown fluid. As the blisters burst, the skin sloughs off.
One waste product of all this bacterial activity is gas, and so now the body begins to swell. First the genitals become bloated, followed by the face, abdomen and breasts. Then eyes and tongue protrude as bloody liquid is forced up from the lungs, leaking from nose and mouth. The face, with its popping eyes and tongue, has a look of amazement.
Those officers who could look at the screen – and many chose not to – stared back at the body I showed them with equal amazement. Swelling bodies at this stage of decomposition become so dark that anyone finding one can wrongly assume a skinny Caucasian was in life an overweight black man.
Flies have a role to play in putrefaction by feasting and laying their eggs, which turn into maggots with voracious appetites. Animals, domestic and wild, may also make an important contribution to bodily breakdown (outside there are rats and foxes and inside … well, yes, a starving dog which finds itself locked in the house after a death will probably eat its owner to survive).
Within about a week of death – depending as usual on the weather and micro-environment – body cavities will burst and tissues will start to liquefy. Within about a month, the soft tissues are all liquid and these will drain off into the ground. The usual order of decomposition is first the intestines, stomach, liver, blood and heart. Then the lungs and air passages. Next the brain, then the kidneys and bladder. Finally the muscles. The prostate, the uterus, the tendons and the ligaments are relatively resistant to putrefaction and may not break down for months to leave the skeleton stripped. I didn’t show any pictures of this final part of the process. They looked as though they had seen enough.
A much more unusual form of decomposition in this country is mummification. Mummified bodies are brown and dry. The skin is drawn tightly over the skeleton so it looks shrivelled and tough like leather. This process dries the tissues, hardening them in a way that prevents putrefaction. It usually requires hot, desert-like conditions: bodies buried in the sands of Egypt may even mummify spontaneously.
In the UK, mummification can happen if a thin person (the thin are more likely to cool and desiccate quickly) dies in a very dry and draughty place – an attic or chimney, for instance. It is rare to find a mummified body now but not so long ago they were encountered relatively often.
‘Anyone here seen a mummified body outside the British Museum?’ I asked my audience. A few raised their hands.
One of the older officers said, ‘Baby. Been hidden in the attic. And not yesterday, either. Years and years ago, probably during the war they said, because it happened a lot then.’
‘Was it a newborn?’ I asked.
He nodded. I had actually recently seen a mummified newborn myself, and the circumstances had been the same. The bodies of newborn babies are relatively sterile, which makes them less susceptible to putrefaction and more likely to mummify. Those babies were generally born in secret to single mothers in the days when this was truly shameful. Either they were born dead, or they died at birth as the mother struggled to cope alone, or they were actually killed but, in many cases, burial was apparently not an option and so
the body would be hidden under the floorboards or in the attic. As social attitudes to birth outside marriage changed, these discoveries decreased, but in the 1980s they still sometimes happened when old ladies died and young couples bought their houses for renovation – to find, in the loft, the tragic, long-hidden, mummified corpse of a tiny baby.
There are a few examples of adult homicides revealed years later by the discovery of a mummified body. Most famous is a case in Wales where a strangled woman was hidden in a cupboard for years while her family continued to claim her pension. Once completely dried, a mummified body can last a long time. But eventually mould forms and the dried tissues gradually become powdery and disintegrate. The mummy very often attracts rodents, beetles and moths, too. However, if it is recovered in time it can very faithfully reveal through preserved bruises, abrasions or other injuries, the cause of death.
The third process of decomposition is adipocere, a rare chemical change in the body’s saturated fat, which hydrolyses it, stiffening and swelling it into a waxy compound, a bit like soap. It is sometimes called ‘corpse wax’ or ‘the wax of graveyards’. Basically, the body, or part of it, is preserved, looking as though it is a waxwork.
In the UK, the process of adipocere formation takes about six months – although I have heard of a case just three weeks after death that presumably was aided by the sun’s heat and the warmth of maggot infestation.
Adipocere requires damp conditions. In its early stages, when the fat is hydrolysed into a greasy semi-fluid, the rancid smell is terrible. But, as the process progresses, the fat becomes brittle and paler and when the adipocere is fully formed it is grey and firm.
The phenomenon of adipocere has been documented for many years and it can last literally centuries. Otzi, the Neolithic hunter known as the ‘Glacier Man’, whose body is on display in Bolzano in the Italian Dolomites, was probably at least partly preserved this way. In the eighteenth century, excavations at the Cimetière des Innocents in Paris allegedly yielded tonnes of adipocere, and it was promptly put to use by the city’s soap- and candle-makers. There were some famous cases in the 1970s from Australia where the process perfectly preserved the form if not the contents of divers’ bodies found about a year after they drowned due to equipment failure as they explored a deep freshwater lake.
On occasions, adipocere has revealed a cause of death, perfectly reproducing injuries like bullet holes or preserving the fat in certain organs. In general, it is more commonly found in women, the well-nourished and the obese, but conditions have to be right – usually the body must have been submerged in water anaerobically or buried in a damp grave, especially if there is no coffin and especially if the deceased is wearing natural and not synthetic fibres. Its formation can be influenced by the season, the depth of the grave, coffin composition, the soil and the local insect activity.
These three processes of decomposition – putrefaction, mummification and adipocere – are not mutually exclusive. All three could, in theory, be found in different areas of the same body, although that would be extraordinary as each requires such different conditions. But two processes have been found together – and putrefaction is always one of them.
Although it is common now to short-circuit the natural rotting processes I have described by cremation, the traditional place for human remains in this country is the cemetery. Burial tends to delay decomposition. In fact, a body above ground is said to decompose at least four times faster than one buried. Under ground, it probably takes two years for the soft tissues to disappear completely. Tendons, ligaments, hair and nails will be identifiable for some time after that. In about five years the bones are bare and disarticulated but there are often fragments of cartilage and, if I use a high-speed saw to cut the bones of bodies that have been exhumed after five years, there is a wisp of smoke caused by scorched protein still in the marrow and the smell of burning organic matter – something I can also expect from the bones of the recently dead.
The human skeleton is the last part of the body to return to the earth, which, of course, can take a very long time: hominid bones more than 2 million years old have been found in dry parts of the world. Unless preserved anaerobically in a bog, the damp UK climate does not keep bones so well. And eventually, all bones must decompose. Wet soils that hold water hasten this by leaching the calcium and other minerals away. As the bone becomes more porous, the process of disintegration is helped by bacteria, fungi and even plants thrusting their roots inside the cracks and crevices and breaking up the bone more – as well as by gnawing animals.
Throughout their careers, pathologists are approached by the police to examine bones. I asked the attendees if anyone had submitted found bones to a pathologist and two people put up their hands. Usually just one bone is found, sometimes a collection, and they are nearly always from animals. But not always. All pathologists have files labelled ‘Old Bones’ and every attempt is made to identify these finds. Some bones, like the pelvis or the skull, tell us at a glance whether its owner was male or female. Other bones, and particularly teeth, can tell us the age of the deceased if they were very young or very old. Otherwise, judging age from a skeleton is not a precise science.
For the most part, our ‘Old Bones’ files remain mysterious. Our main task is to date the bones and discover whether this death, possibly a criminal death, occurred in the last sixty or seventy years, in which case the killer might still be alive. Dating is a specialist skill. Carbon-14 dating only works to a very long time-scale but the atomic bombs of the 1940s, with their release of strontium-90 into the atmosphere, mean it is relatively easy to discover whether bones pre- or post-date these explosions. If they predate the atomic era, the police are seldom interested, although archaeologists might be.
At the end of the talk, most of the officers made a dash for the bar. There was an orchestra of cigarette lighters clicking outside the door. One detective did approach me, however. He was the older man who had been involved with the case of the mummified baby.
‘Thanks for that, Doc,’ he said. ‘I’ve been haunted by that baby. And by another one, a body which had been sitting in his armchair for almost a year when we found him. I dream about them sometimes. But when you talk about the science of it … well, that made me feel a bit better. I even found I could look at the pictures you showed us today.’
This was a rare example of an officer of that era admitting to vulnerabilities. And his words stayed with me. I resolved to redouble my efforts to talk during post-mortems. I should not just say whatever came into my head, but present the body in a detached, scientific way which would help onlookers quash the very unscientific emotions they might be feeling.
12
Very shortly after that talk came my first defence case.
So far I had only ever been called to a death by the police or the coroner. That meant I was, almost automatically, adopted as an expert witness for the prosecution if charges and a court case followed. Sometimes the pathologist’s report alone will satisfy the court, sometimes a court appearance to answer questions is required. The most searching questions, of course, come from the defence barrister.
The defence team will usually call a forensic pathologist too, and they probably will ask for a second post-mortem. On occasions, when a whole group of people is accused of the crime, there may be more defence teams ordering a third, a fourth and even more post-mortems. In these rare cases, all the defence pathologists might perform their post-mortems consecutively, but more usually together, observing each other’s work, clustering around the body like moths around a lamp. Then, if we go to the pub afterwards, it looks like a pathology convention. Each pathologist will write a report for the prosecution or for one of the defendants, each report will be used as evidence, each pathologist may be called as an expert witness.
You might assume pathology is such a precise science that all reports on the same body must be identical. This is not the case. Wounds and injuries recorded identically may be interpreted differently.
Interpretation can be influenced by many things, especially the information supplied concerning a case: the more information there is, the less likely that conclusions may be erroneous.
So, as the pathologist on call one night, I might be summoned to the scene of a crime by the police and subsequently write a detached, scientific report based on all the evidence at my disposal. This would be used by the Crown Prosecution Service in deciding whether or not to prosecute the alleged killer. I’d probably then have to give my evidence in court for the prosecution. However, if I’d just come off duty when the police’s call came, one of my colleagues would attend the scene instead but a few weeks later I might nevertheless find myself working on the same case – for the other side, after a call from the defendant’s solicitor.
At the very least, defence lawyers require corroboration of the first pathologist’s findings and report. But some defence teams are hoping for more than that. They would like their pathologist to find an error in the original report – which is rare, but still they hope for information which might help exonerate their client. They at least expect a wide-ranging review of alternative explanations or interpretations of the findings and facts.
Defence reports are a normal part of a forensic pathologist’s workload, but it takes a while for defence lawyers to learn a newcomer’s name, so no defence case came my way for some time. I wasn’t sorry. I knew how hard it can be to carry out a post-mortem on a body already examined by another pathologist. I mean, how technically difficult: there will be an inevitable degree of deterioration, whether the body has been frozen or just kept refrigerated; further bruising may appear and wounds may change size; organs are occasionally absent when they have been submitted for another expert opinion and tissues have usually been sent away for analysis. However, all the information the later pathologist needs should be available, whether these are found in colleagues’ notes or in the scene-of-crime pictures, reports or tissue samples.
Unnatural Causes Page 10