Pat Jamieson, who is going to fill us in on some of the details.’
Murfin groaned dramatically, as if he’d been shot. Despite himself, Cooper couldn’t help laughing.
‘Superintendent Branagh has expressed a firm view on this,’ said Hitchens, as if he’d anticipated resistance. ‘She thinks we should be fully briefed by the forensic specialists. We ought to make full use of their expertise while we have them on the payroll, so to speak. The superintendent believes we’ll all benefit from the insight.’
Murfin was making noises as though he was going to be sick. Hitchens looked at him.
‘And she emphasized that it should be the
When Dr Jamieson entered, he looked as surprised as anyone to be sitting in a meeting room with a bunch of DCs who thought they had better things to do. Cooper wondered who had twisted his arm. The mysterious Superintendent Branagh, perhaps?
Jamieson rallied bravely, despite the chilly atmosphere. He became professional after he’d set up his laptop and screen, and began his presentation.
‘Well, there are four things we might hope to establish from decomposed or skeletalized remains,’ he said. ‘Sex, race, age and stature.’
‘And cause of death?’ suggested someone hopefully.
Jamieson turned to Hitchens. ‘Inspector, you know I can’t address — ’
‘Yes, I know. Carry on, Doctor.’
The anthropologist hesitated. ‘I see. Well, let’s press on. First comes sex.’
He seemed to notice Gavin Murfin’s expression out of the corner of his eye and hastily amended his words.
‘Ah … first comes gender. As a rule, it’s easy to determine gender in adults if the remains include the pelvic bones. The pelvis of a woman is generally broader than that of a man. It has to be wider in females because it surrounds the birth canal, and a baby’s head has to pass between the bones of the pubis. Without the pubis, the probability of making a correct identification of gender declines. Generally it comes down to size differences, but there’s a certain amount of overlap in the middle. There are approximately ten per cent of individuals who confuse the middle ground.’
‘We do have some very large young women walking around Edendale.’
‘It’s not a question of obesity,’ said Jamieson, ‘but of height, the width of the shoulders, the density of the bone …’
‘And in this case …’
‘In both cases, the pelvis was clearly female. It was obvious even in the field. For both Victim A and Victim B, the pelvis is broader at the hips, with a raised sacro-iliac joint, a wide sciatic notch, a greater sub-pubic angle. All part of the geometry of birth. The skull can also be a help, but of course …’
‘We don’t have two skulls.’
‘Not for Victim B. No, we don’t.’
Jamieson paused, allowing for more questions. ‘Now, race is a question we’re often asked to pronounce on. But it’s getting more difficult. Some characteristics of particular populations are evident in the skeleton, but there’s a lot of variation, even within groups that are historically pure. In the case of Victim A, we have the hair mat, which had sloughed off the skull. As you can see from the first picture, it’s very dark brown and slightly wavy. That, plus the shape of the teeth, mark the victim as white, where the discoloured skin might have been misleading.’
‘And Victim … I mean, the second woman?’ said Fry.
‘We can’t be sure, Sergeant. Completely skeletalized remains, and the absence of a skull — well, I’m sorry, but …’
‘OK.’
‘Now, age. By the time a person reaches the age of twenty, most bone growth is complete, the epiphyses are united and most teeth are fully calcified. So we look at several different structures: skull sutures, clavicles, pelvis.’
Jamieson presented another series of photographs on the screen.
‘In Victim A, the bones of the pelvis were dense and smooth, with a marked absence of grain; the bones of a mature but young woman. Her clavicles had not fully matured, and the basilar structure in the skull was only partly fused, an indicator that she was not yet twenty-five. Factoring all the indicators together, I’m confident that Victim A was somewhere between twenty and twenty-five. Victim B is a little older, fully matured. Without the skull, it’s difficult, but I’d say between twenty-five and thirty.’
‘Height, Doctor?’
‘To estimate height, we turn to bone measurements and regression equations.’ He seemed to sense the shuffling and muttering. ‘Yes, I know it sounds like scientific jargon. What it means is that we can predict stature from the length of the femur, for example. Multiply by one number, add another, and bingo. For Victim A, length of the left femur is forty-four centimetres. Using the stature calculation formulas, we estimate she stood between five feet one and a half inches and five feet four and a half.’
A few officers were at least making notes, having detected some facts in the doctor’s presentation.
‘And the skeleton?’ someone asked.
‘Yes, Victim B. You’d think we could just lay a skeleton out and measure it to get the victim’s height. But cartilage decays and shrinks after death, sometimes by several inches. In Victim B’s case, the femur is forty-eight centimetres, giving a height of between five feet six and a half inches and five feet nine and a half inches.’
‘How accurate are these ages and measurements, Doctor?’
‘I’m confident the estimates are accurate, within the parameters I’ve given you. But I’d like to urge the police officers present to be careful with their missing person reports when trying to make a match. Don’t assume any degree of accuracy there.’
‘Why not?’
‘Well, a lot of people don’t actually know how tall they are. Or they lie about it. Some would like to be a few inches taller, others a bit less tall. And of course, they don’t realize that their height changes when they age, so they can be giving the wrong height for themselves for years without knowing it. Besides, if you’re looking at a missing person report, ask yourself who provided the information? A spouse, a friend? Some of those figures could just be a wild guess.’
Jamieson took advantage of the silence he’d created to press on hurriedly with his final point.
‘And how long have the remains been buried, you’ll ask me. Well, an unembalmed adult body buried unprotected in ordinary soil will normally take ten to twelve years to decompose down to a skeleton. Burial depth and soil temperature might vary the decomposition rate. A body in air decomposes eight times faster than when buried.’ He looked up from his laptop. ‘Like Detective Constable Cooper’s dead sheep.’
Gavin Murfin laughed, but no one else seemed to understand the joke. The anthropologist moved on rapidly.
‘When bodies are exposed to cool, moist soil, the soft tissues can decay quite slowly and turn into adipocere. Adipocere is a soapy, greasy substance that forms when body fat decomposes in a damp environment. It’s sometimes called grave wax. Adipocere is the cheesy greyish-white mass you can see in this photograph.’
Yes, they could see it quite clearly on the photographs. Some of the officers looked away for a moment, but forced themselves to turn back. Jamieson left the most revolting photograph on screen while he finished off.
‘Adipocere inhibits putrefying bacteria, so when a body reaches this state of decomposition it might stay that way for several years before it decomposes any further. There was a large quantity of adipocere beneath the chest and abdominal regions in the case of Victim A. So I would say you have the cold, wet soil of Rakedale to thank for the relatively intact condition of this body. If I might offer a very non-scientific comment, it’s almost as though Victim A has been waiting in her half-decomposed state for someone to find her.’
Jamieson smiled as he diverged from his professional approach for a moment. He waited for comments, but none came.
‘Finally, then,’ he said. ‘There was no sign of trauma on either victim — no fractures, cut marks, or signs of perimortem damage on any of the bones we’ve recovered. But we don’t have every bone for Victim B. As we’ve already mentioned, there is no skull. And, before any of us run away with assumptions, I should mention that it’s very common for the head to come off when a body disarticulates. With the skull, we have one of the heaviest parts of the skeletal structure, supported by one of the most fragile.’
The anthropologist finished with a flourish, closing his laptop and waving his arms in a graphic gesture.
