Describe the identification of skeletal, mutilated and mass disaster remains.

Examination of Skeletal Remains

• 1. Is it bone? — distinguish from wood, plaster, stone and plastic by appearance, weight, texture and, if necessary, histology and chemical tests → 2.
• Is it human or animal? — by gross morphology
• by histology, since animal bone shows plexiform (banded) architecture whereas human bone shows haversian systems
• by precipitin test or DNA where doubt remains → 3.
• Are the bones from one individual or more? — by counting duplicated bones, and by checking consistency of size, age, sex and colour → 4.
• What is the sex? — pelvis and skull, as above → 5.
• What is the age? — ossification and epiphyseal fusion up to about 25
• thereafter sutures, pubic symphysis, sternal rib ends, degenerative change and Gustafson's dental method → 6.
• What is the ancestry? — from the skull, given as a probability → 7.
• What is the stature? — from long bones, using Indian formulae → 8.
• How long since death? — and what was the cause of death, from any injury or disease evident in the bones → 9.
• Identity — by dental comparison, antemortem radiographs (especially the frontal sinus), prostheses with serial numbers, superimposition and DNA
• Time since death from bones — recent bone is greasy, retains soft tissue and periosteum, is heavy and yields ultraviolet fluorescence of the cut surface; with time the bone becomes dry, light, brittle and earthy, loses fluorescence progressively from the periphery inward, and gives a negative benzidine and precipitin reaction. Nitrogen content below about 2.5% and absence of amino acids suggest more than about 100 years. All such estimates are very approximate and depend heavily on the burial environment
• Bone is a poor recorder of soft-tissue cause of death, and in most skeletonised cases the cause cannot be established; injuries to bone — fractures, cut marks, gunshot defects — may be identified and dated as antemortem, perimortem or postmortem by the presence of healing and by the fracture characteristics of fresh against dry bone

Mutilated and Dismembered Remains

• Dismemberment is usually defensive — to conceal identity and to facilitate disposal — and much less often offensive (part of the act itself) or aggressive in a psychiatric or ritual context
• The examination must establish — that the parts are human; that they belong to one individual (by blood group, DNA, anatomical fit at the divided surfaces, and consistency of build and colour); the sex, age and stature; the cause of death, which is often established from the head or trunk if recovered; and whether the dismemberment was antemortem or postmortem, which is determined by the presence or absence of vital reaction and of bleeding at the cut surfaces
• The instrument used may be inferred from the cut surfaces — a saw leaves parallel striations and a "false start" kerf; a heavy sharp weapon leaves clean division with chipping; and the level of division often follows joints where the perpetrator had anatomical knowledge, or crosses bones where they did not
• Reassemble and photograph the parts in anatomical order before any further examination

Mass Disaster Victim Identification

• Disaster victim identification (DVI) follows the interpol protocol, and is organised in four phases: the scene (recovery, numbering and documentation of every body and fragment in situ); postmortem data collection; antemortem data collection from families and records; and reconciliation, in which the two data sets are matched
• Primary identifiers — accepted as conclusive on their own: fingerprints, dental comparison and DNA
• Secondary identifiers — supportive but not sufficient alone: medical findings including implants and old fractures, tattoos, scars, personal effects, clothing and jewellery
• Visual identification by relatives is the least reliable and is not accepted alone in a disaster; distress, expectation and disfigurement produce confident errors in both directions, and this has repeatedly resulted in the wrong body being released for cremation
• Number and photograph every fragment, and resist the pressure to release bodies quickly; in India that pressure is severe and comes from families, politicians and the press, and it is the principal cause of misidentification
• Take DNA reference samples from relatives early, before they disperse; and collect antemortem records — dental charts, radiographs, fingerprints from employment or Aadhaar records, and photographs

Applied Aspects

• Answer the questions in order — bone, human, how many, sex, age, ancestry, stature, time since death, cause, identity; skipping to identity is the commonest error and produces unsupportable opinions
• Preserve a femur and a tooth for DNA from every unidentified remains, irrespective of how confident the identification appears; the material cannot be recovered once the remains are released
• Do not accept visual identification alone in a disaster, and explain to families why the delay exists; releasing the wrong body is far more damaging than releasing the right one late
• Histology distinguishes human from animal bone in minutes and should be done early, before an investigation is built on remains that turn out to be a goat
• Perimortem and postmortem bone injuries differ in fracture pattern, because fresh bone is elastic and dry bone is brittle; state which and give the reasoning, since it determines whether the injury is relevant at all
• Work as a team — forensic pathologist, odontologist, anthropologist, radiologist and DNA laboratory; skeletal and disaster identification is the clearest instance in forensic medicine where no single discipline is sufficient
• Establish that the parts belong to one person before reasoning about anything else; a mixture from a disturbed burial or from two victims will otherwise produce an impossible composite profile
• Look for vital reaction at the cut surfaces in dismemberment; whether the division was before or after death changes the offence entirely
• Resist pressure to release bodies quickly in a disaster; the wrong body cremated is an irreversible harm, and the pressure is greatest exactly when the risk of error is highest