Facial appearance
Even in perfectly fresh bodies, recognition may be difficult because of alterations in the features caused by death. It is a common occurrence in mortuary viewing rooms for a close relative, even a parent or spouse, to have doubts about – or even to deny or mistakenly agree to – the identity of the deceased person. Though distress and emotion play a part, changes in the features may be profound. Hypostasis, con- tact flattening, oedema, muscle flaccidity and pallor may all combine to distort the face. Recognition in the living is partly a dynamic process, aided by facial muscle tone and especially eye contact and movement, all of which are absent in the corpse.
Eye colour
In the fresh corpse, eye colour corresponds with the living state, but it quickly deteriorates. Loss of intraocular ten- sion and clouding of the cornea develops progressively within a few hours, making the iris harder to observe.
Collapse of the front of the globe occurs within a day or two and, with developing decomposition, all irises tend to darken to brown. It is unsafe to depend on eye colour as a criterion of identity later than a few days following death – or even much sooner where environmental conditions hasten decomposition.
Skin pigmentation
In undamaged, unputrefied bodies, the major ethnic differ- ences in skin pigmentation are obvious, though the slight melanin increase of the misnamed ‘yellow’ races of Asia
may be impossible to differentiate from Mediterranean or Middle Eastern races. The onset of deathly pallor and post- mortem hypostasis is more profound than slight variations between sunburnt White people, northern Asians or Semitic races. When putrefaction sets in, skin slippage progressively removes the pigmented layers and eventually pigmentation becomes unavailable as a marker of identity, though histologically melanin may still be visible in the basal layer of any surviving epidermis.
Burnt bodies may also lose pigmented skin, either by heat destruction or by deposition of soot and other com- bustion products on the surface, though it is rare for this to be so complete as to obscure all evidence of pigmentation.
Hair colour
The head, pubic and axillary hair is one of the most resist- ant identifying features, sometimes lasting millennia in favourable environments. The original colour may, how- ever, alter after burial, becoming a brownish-red or ‘foxy’
colour within as short a time as 3 months. The colour may be obscured by dirt or staining and expert treatment (usu- ally by a biologist or museum technologist) may be required to restore the original colour. The possibility of deliberate chemical coloration or bleaching before death may have to be considered and again expert chemical analysis in a forensic science laboratory may be needed to confirm or eliminate this if the hair colour conflicts with other positive evidence of identity.
Hair structure
This is more the province of the forensic biologist or anthropologist, but factors such as whether the hair ends have been cut or are naturally pointed may sometimes have importance in identity. Racial features exist, Negroid head hair being dark and having a spiral twist with a flattened, elliptical cross-section. Mongoloid hair is less pigmented and is straight with a cylindrical cross-section. Caucasian hair is round or ovoid in cross-section, but shows great variation in colour and morphology compared with the other two major ethnic groups. Though head hair in Caucasians is round to ovoid in section, eyebrow hair tends to be triangular and pubic hair flattened. Where a hair root is present, blood grouping and other serological criteria can be determined. Grouping of the shafts of hairs has been repeatedly attempted and success claimed by some workers.
The cells of the hair root can give a DNA profile and mito- chondrial DNA (mtDNA) has been detected even in a sample from a single hair shaft.
Microscopic examination of the hair can assist in deter- mining the species, if not human. Human hair has broad
groupings when viewed microscopically. However, the topic of individual identity from hair is now the province of foren- sic biologists, and has a specialism and literature of its own.
Tattoos
Deliberate ornamentation of the skin by introducing pig- ments under the epidermis has been practised for millennia and in all parts of the world. The word ‘tattoo’ comes from the Polynesian ‘ta tau’, meaning ‘to mark’. Some races such as the Ibans of Sarawak may be tattooed over much of their body surface, but many men and some women in most countries have localized tattoos, which can be of consider- able assistance in identification. Many different pigments are used, as well as more unusual substances such as soot or gunpowder. The colour is pricked into the upper dermis with a sharp instrument, usually a needle used manually, or by an electric vibrator.
Once under the outer skin, the material persists for a long time. Colours such as blue, green or red may be scav- enged by tissue cells and leached into the lymphatic system after a number of years or decades. Black pigments, usually carbon particles in the form of Indian ink, are so resistant as to be virtually lifelong, though some may be transported to regional lymph nodes. Thus an original pattern of dif- ferent colours may fade differentially over years, the black areas standing out in strong relief.
The patterns are so diverse as to defy classification, though much has been written on the subject. From the point of view of identity, tattoos may be useful in both a general sense and for comparison with potential victims.
The general applications require a knowledge of ethnic, national, cultural, religious and social practices, so that the tattoo can be assigned to some particular group of people.
In Western society, the popularity of tattooing changes from time to time. Former statements that tattoos are seen mostly in the ‘lower social classes’ have little current valid- ity, though it is obvious that bankers and parsons are less likely to sport tattoos than seamen and truck drivers. It is also now totally anachronistic to claim that most women with tattoos are prostitutes, though the nature and position of the tattoo is obviously relevant.
Certain tattoos have had particular significance such as a number, often ‘13’, inscribed inside the lower lip of drug pushers or the bluebird on the extensor surface of the web of the thumb in homosexuals. The latter design is now so common as to be of little significance.
Tattoos are of most use when individual enough to be compared with known designs on a missing person. The design is often supplemented by actual names, though these are mostly forenames rather than family names.
Designs are by no means unique and a professional tat- tooist may turn out hundreds of identical decorations, so names are a bonus when trying to achieve identity.
Initials may be used, but these can be misleading due to the use of nicknames and diminutives, such as ‘B’ for Bill, rather than William. In general, men have the names of girls on their tattoos, but initials are usually their own. Conversely, women with tattoos almost always display the names of sweethearts, rather than their own. Some tattoos may be numbers or unadorned names, the most tragic examples being those from Nazi concentration camps during the last war.
FIGURE3.1 Individualistic tattoos may assist the identification of unknown persons.
The photography, distribution and matching of tattoos is police business, but the pathologist’s duty is to make them accessible and clear to the police. Where decompos- ition has set in, tattoos may be obscured by wrinkled, peel- ing epidermis, but often this can be wiped off to reveal tattoos that are more vivid than on fresh skin. Once the tissues become green and slimy, then the pattern progres- sively vanishes, but early decomposition is no barrier to recognition. Where skin pigmentation may hide a design, skin slippage may actually enhance the clarity, especially of the weaker colours like blue, red and green. Attempts at the deliberate removal of tattoos are common, either from regret at having disfigured the body during youthful or drunken euphoria, or to remove evidence of identity. Many methods have been used, from surgical excision to scarifica- tion with sandpaper and from caustic soda to electrolysis.
All methods depend upon damage to the epidermis and dermis, with consequent inflammation and scar formation.
The tattoo can certainly be removed, but always by replacing it by a cicatrix to a greater or lesser extent, which will itself indicate that something pre-existed at that site.
It has been suggested (PA Edwards, personal communica- tion) that the chemical nature of tattoo pigments might be used in identification. Although all manner of substances have been used to tattoo, most tattooists use black pigments con- taining carbon, green pigments containing potassium dichro- mate and red pigments containing mercuric chloride. Others use aniline-based dyes, so that microextraction and analysis in a forensic science laboratory might confirm or exclude the tat- too having been executed by a particular artist in the locality.
Finger , palm, foot and lip prints
The science of fingerprints, their classification, retrieval from records and methods of recording lie in the domain of police procedure, and, as with tattoos, the pathologist’s role is merely to facilitate the taking of prints by police officers.
Sometimes when a strange print is found at a scene of crime, the police may wish to take the fingerprints of doc- tors who visited the locus to eliminate them from their enquiries and there is obviously nothing objectionable about this. Indeed, some forensic pathologists who habit- ually assist the police leave their prints on file so that they are permanently available for exclusion. When called to a scene of death, the doctor should take care to avoid handling objects and furniture to reduce the need for such laborious screening of prints.
The doctor need know nothing about fingerprints except for his own interest, though it is as well to be prepared for the inevitable questions – no two fingerprints have ever been found to be identical and even identical twins have different prints. However, some recent claims point out that some prints are so similar that the criteria usually accepted as proof of congruence may not be sufficient. Police usually attend the mortuary to take full sets of fingerprints in the usual way by rolling ink on to the finger-pads and pressing the pulps against record cards.
The pathologist may help when there is strong rigor present, by either forcing the flexed fingers back or even by slitting the flexor tendons, though this has the danger of fouling the fingers with blood.
Characteristics useful in identifying the dead
FIGURE3.2 Shoulder region of a decomposed body recovered from the sea showing a tattoo with Cyrillic letters ( ) and a flag with a star and hammer and sickle suggesting a connection with the Russian Baltic Fleet.
D,K,B,F
When the body is putrefied, the doctor can again assist by removing desquamated casts from the fingers for the police.
These may need to be preserved or hardened up so that the decaying tissue does not lose further definition from the ridges that form the prints. The skin may be placed in for- malin, alcohol or glycerine solution, especially where macer- ation in an immersed body has caused swelling and blurring of the epidermis. An alternative is immersion in 20 per cent aqueous acetic acid for 2–8 hours. Rarely, a criminal may attempt to obliterate his fingerprints by scarring the finger- pads. To be effective, this must be drastic enough to damage the underlying dermis and the consequent cicatrices will be more obvious than the original prints. Surgical grafting of skin from elsewhere on the body has been reported as a means of removing fingerprints, but again the result is self- evident proof of nefarious intent.
As with fingerprints, the skin pattern of palms, soles and even lips are said to be unique and have been used in identi- fication, but again this is really police business. The pattern of veins on the back of hands is also said to be characteristic to one individual.
Identifying scars
These can be important in the identification of unknown bodies, even when some degree of putrefaction exists. The author (BK) used a cholecystectomy scar and scars of old surgical incisions on the legs to identify the body of a homi- cide victim submerged in a river for 6 weeks and many other cases are on record where scars provided similar vital infor- mation. Probably the best known instance is the Crippen case of 1910 in which much forensic controversy was gener- ated over the distinction between a surgical scar and a skin crease on a piece of abdominal wall.
Scars on the skin may arise from any previous injury that has breached the epidermis, as superficial injuries to the upper layer of skin will heal without a trace. Where the der- mis has been entered, healing occurs by organization of the plug of blood clot and/or granulation tissue, as described in Chapter 4. If the wound is narrow, such as that inflicted by a surgical instrument, sharp knife, razor or glass, then if the edges are kept together, especially by stitches or dressings, the resulting scar will be narrow and insignificant. Gaping or infection will widen the scar and obviously larger lacerations or burns will result in similarly greater scarring. In relation to identification, scars are of use only if those thought to be the victims are known to have similar scars, both in nature and position. The specificity of scars varies greatly, as many people may have appendicectomy scars, and many women have had hysterectomies or other gynaecological operations that leave lower abdominal scars. As always, scar evidence must be taken in conjunction with all other details of identity,
but where a cicatrix is unusual or even unique in nature or position, its value is greatly enhanced.
Turning to traumatic scars other than surgical, the pathologist may be able to recognize the cause, which can assist in identity. Naturally the vast majority of non-surgical scars are the result of accidental trauma and where family, friends, photographs or medical records indicate the exis- tence of specific scarred sites on the body, then confirmation of identity may be greatly assisted or confirmed.
Some scars are deliberately produced as part of some ethnic or religious tradition, such as the facial scars in some African tribes, as well as deformed or perforated ear lobes or lips.
Regrettably, another class of scars is becoming more common in many parts of the world, due to physical torture; this is dealt with in Chapter 10. Linear scars, cicatrices of burns, keloid overgrowth (especially in negroid races), hyperpigmentation or depigmentation and other persistent lesions may assist in identity in the appropriate circumstances. Much depends on the accuracy of the information concerning the person thought to be the victim; relatives are notoriously vague and inaccurate about medical matters and frequently confuse dif- ferent surgical operations, thus misleading the investigators about scars. Sometimes surgical scars may be almost invisible.
The author (PS) once worked as surgical assistant in a private hospital where one of the surgeons used to perform appen- dicectomy (in non-acute cases) through a 1cm wide incision, closing the wound, for cosmetic reasons, with subcutaneous catgut sutures. Most of these wounds healed with virtually no scar whatsoever, unless the person had a tendency to keloid formation. Wherever possible, old hospital records or the notes of a family physician should be obtained.
The old scars of wrist- or throat-slashing indicate previous attempts at suicide. Large areas of scarring on the trunk or limbs that have parallel grooves and marginal extensions sug- gest severe brush lacerations, probably from a traffic acci- dent. Knife stab wounds may scar in an elliptical fashion, sometimes even with a blunt and a sharp end indicating the position of a single-edged blade. Bullet wound scars may persist – and in 1989, became a matter of political controversy over the identity of Nazi war prisoner Rudolf Hess, who was alleged to have been an imposter because he had no scar from an old rifle bullet wound through the chest. Burns may provide good evidence of identity, especially if they are wide- spread cicatrices that may have been quite noticeable during life. Many scars on the fronts of the lower legs may indicate the repeated stumblings of a chronic alcoholic, who fre- quently walks into or falls over furniture.
The age of scars
The age of a scar is very difficult to assess and, once it becomes mature, no change will occur for the rest of the
Characteristics useful in identifying the dead
person’s life. When a linear wound is inflicted, be it a surgi- cal operation or a knife slash, the edges become mechan- ically strong within a week, assuming that no infection or haematoma develops. The wound is brownish red at this stage and remains vascular for several months, depending upon its width. The pinkness of contained blood vessels gradually fades and a narrow surgical incision may be white by 4–6 months. The avascular collagen tends to shrink for a year or so, but is white–silver after a year and remains in this state indefinitely. These times are variable depending on the nature of the skin, its pigmentation and the part of the body involved. Where a wound crosses a skin crease that is frequently flexed or extended, it tends to gape and widen, the subsequent scar following suit.
Histology does not contribute much to the examination of scars, except to confirm that a skin mark actually is a scar. Stains for collagen or elastin may confirm the discon- tinuity in the dermis. Scars do not carry hair follicles, sweat glands or sebaceous glands, though an occasional accessory skin structure may be present as a result of the inclusion of a viable fragment of original skin in an irregular wound – or where surgical repair has detached or invaginated a piece of the margin.
Occupational stigmata
Formerly given prominence in most textbooks, distinctive physical marks of occupation have decreased in incidence and importance. They are still of use in certain areas, but local knowledge of occupations and industries is required.
The Victorian days of pen callosities in clerks and shoe- maker’s kyphosis have gone, but many other occupations have their stigmata, though most are relatively non- specific. The best known is the ‘blue scar’ of coal-miners, an involuntary tattoo caused by dust entering small lacerations on the hands and face. Some miners and quarrymen also have small facial scars due to rock splinters scattered during blasting. Steel workers and foundry men may have tiny burn scars on exposed areas from the spattering of hot metal.
In more general terms, examination of the hands will indicate whether the deceased was a manual worker or involved in more sedentary occupations. Cuts, scars, callosi- ties and hyperkeratosis of the hands are obvious indicators of rough work.
Internally, black, dust-laden lungs – with or without pneumoconiosis – points to mining, as coal trimmers no longer exist as dock workers. Thickened, pearly plaques on the parietal pleura and diaphragm are caused by exposure to asbestos, though in recent years the widespread use of this substance in so many industries makes it less helpful in identifying the occupation.
The stature of an intact body
The stature of a corpse is not necessarily exactly that of the person measured during life. In the mortuary, care must be taken to measure the body from heel to crown, and not to accept the mortuary attendant’s or funeral director’s
‘coffin measurement’, which is made from toe to crown.
Because of the usual plantar flexion of the foot, this latter height may be as much as 10 cm longer than the heel–
crown length.
The height of a dead body may differ from the height during life in either direction, being slightly longer or shorter, though lengthening is much more common. In addition, the measured height may change a little at different periods after death. Because of the complete loss of muscle tone in the first stage of flaccidity, relaxation at large joints, such as the hip and knee, together with the lost tensioning effect of paraspinal muscles on intervertebral discs, the body may lengthen by up to 2–3 cm. Rigor mortis may then replace FIGURE3.3 Careful external examination may yield evidence that can assist identification. The small ‘blue scar’ on this forehead establishes that the deceased had been a coal-miner; coal dust enters small lacerations and remains visible after healing. Virtually every coal-worker has such marks on hands or face.