Examination of Bundle of Bones - Reddy's Forensic Medicine (36th Ed., 2026)

a) How will you proceed to Examine and Give an Opinion?

Scene Protocol (Before Disturbing Anything)

• Photograph the scene before anything is touched or disturbed.
• Keep the bones in anatomic arrangement and draw a skeletal chart indicating which bones are present.
• Prepare a complete list of all bones sent for examination and photograph all of them.

General Description and Initial Preparation

1. Remove sand, dust, or earth on the bones using brushes and wooden picks/scrapers. Light applications of acetone help remove tight dirt.
2. Note attachment of any soft tissues and their stage of putrefaction.
3. Examine skeletal remains first in the condition they were found, with whatever soft tissues are present.
4. Note whether bones are moist and humid, or dry, and their smell (odor is a good indication of relatively recent death).
5. Wash bones by brushing with lukewarm water and place under shelter to dry slowly.
6. If soft tissues are attached, boil in water for 5-6 hours (young bones) or 12+ hours (adult bones), or immerse in dilute aqueous solution of trisodium phosphate and household detergent (sodium hypochlorite 5-6%) for several days to remove periosteum and soft parts.

Step 1: Are the Remains Actually Bones?

• Stones or pieces of wood are sometimes mistaken for bones.
• Determine by anatomical shape and structure.
• If the bone is too small, subject it to histological examination to confirm it is bone.

Step 2: Human or Animal?

• Knowledge of human and comparative anatomy is necessary.
• Easy when whole skeleton/entire bones are available; difficult with fragmented, burnt, or smaller animal bones (digits, metacarpals, metatarsals may mimic animal bones).
• If bone is fairly fresh with blood constituents present: precipitin test is useful.
• If bones are fresh: DNA analysis from marrow cells can identify species.
• Non-human bones contain sheets of plexiform structures in cross-section on microscopy.
• Human and animal bones can also be distinguished by chemical analysis of bone ash.
• Serological tests are NOT useful if bone is 5-15 years old (no extractable plasma proteins) or burnt/cremated.
• Note: Bones of bears (hand and wrist) may be confused with human hands; bones of great apes cannot be distinguished microscopically from human bones.

Step 3: Number of Individuals

• Reconstruct the skeleton. If no disproportion in size of various bones, no reduplication, articulation is correct, and age/sex/race of all bones is same - they belong to one individual.
• If commingling (mixing) from more than one skeleton is suspected: use a short-wave ultraviolet lamp. Bones of different individuals reflect different fluorescent colors (derived from organic elements, inorganic surface substances and reflected light).

Step 4: Sex Determination

• Recognizable sex differences are NOT present before puberty.
• After puberty, examine:
  • Pelvis (most reliable), skull, manubrium-gladiolus ratio
  • Diameter of head of femur and humerus
  • Measurements of femur, tibia, humerus, and radius
• In parous women: scars of parturition - irregular/undermined dorsal border of pubic symphysis.

Step 5: Age at Death

• From teeth (eruption, wear and tear, dental age)
• Ossification centers and epiphyseal union in long bones
• Pubic symphysial surface morphology
• Calcification of cartilages, changes in sacrum
• Length of long bones

Step 6: Stature Estimation

• Use osteometric board (board with two vertical parallel components) to measure maximum lengths of long bones.
• If bones are covered with articular cartilage, subtract: radius and humerus 3 mm each, tibia 5 mm, femur 7 mm before applying formulae.
• Use weight-bearing long bones: femur and tibia give more accurate results than humerus or radius.
• Average stature from more than one long bone is more accurate than single bone measurement.
• Rule of thumb: humerus = 20%, tibia = 22%, femur = 27%, spine = 35% of individual's height in life.
• In absence of long bones, calculate adult stature from articular length of five metacarpals (Musgrave and Hassal formula).

Step 7: Identification

• Established from:
  • Teeth (dental charts, dental radiographs)
  • Disease and deformities of bone
  • Old healed or healing fractures
  • Orthopedic surgical procedures (implants, fixation devices)
  • Regional atrophy, spinal deformities, flat feet
  • Supernumerary ribs, congenital defects
  • DNA profiling (from marrow cells if fresh; or bone itself)
  • Comparison of previous X-rays (contours, cancellous patterns, pituitary fossa profile)
  • Neutron activation analysis (relative mineral content comparison)

Step 8: Dating the Bones (Time Since Death)

• Nitrogen content: Recent bone has ~4-5 g%; >3.5 g% = less than 50-100 years; >2.5 g% = less than 350 years.
• Amino acids: Fresh bone shows ~15 amino acids (glycine and alanine predominant); >100 years old bone has only 7 amino acids; proline and hydroxyproline disappear after 50 years.
• UV fluorescence: Bone less than 100 years old fluoresces over most of its cut surface under UV light; progressive loss; absent in 500-800 years.
• Soft tissue remnants: Pieces of cartilage and ligament remain attached for 3-4 months or more; traces of marrow and periosteum persist for several months.
• Smell: A good indicator of relatively recent death.
• Texture: A fairly recent bone is slightly greasy to the touch and heavy (due to persistence of collagen and normal apatite matrix).
• Chemical/histological: Ground-sections of long bones or micro-radiographs of un-decalcified sections to detect weathering effects.

Step 9: Cause of Death

• Look for evidence of violence on bones: sharp/blunt force trauma marks, saw marks (dismemberment), bullet entry/exit holes, fracture patterns.
• When force is applied to living or recently dead bone: plastic deformation (bending, twisting, distortion) is possible - especially in skull.
• When force is applied to dry, dehydrated, brittle bone: fracture and fragmentation.
• Repeated freezing/thawing may crack bones buried superficially.

Final Opinion

b) Samples to Preserve and Why

• DNA profiling: Comparison with relatives (parents, children, siblings) for identification of missing persons using single probe analysis (from marrow cells, teeth, or bone).
• Toxicological analysis: To detect poisons, drugs, or heavy metals; bone retains evidence of chronic exposure (e.g. lead, arsenic).
• Serological/species identification: Precipitin test requires tissue with blood proteins (effective only if bone is not >5-15 years old).
• Dating: Nitrogen, amino acid, and fluorescence studies require preserved bone samples.

c) Locard's Exchange Principle

Statement

"Whenever two objects come into contact, there is an exchange of materials between them."

• Dr. Edmond Locard (French forensic scientist, 1877-1966)

Explanation (from Reddy's)

• Traces from the scene may be carried away on the person or tools of the criminal.
• At the same time, traces from the criminal (or any of these) may be left at the crime scene.
• Wherever a criminal goes, whatever he touches, and whatever he leaves will serve as silent evidence against him.

• Fingerprints, footprints
• Hair, fibers from clothes
• Broken glass, tool marks, paints, scratches
• Blood or seminal stains
• Bullets, blood, seminal stains, saliva, pus, milk, poisons, sputum, vomit
• Signatures, teeth marks, footwear impressions, dust, debris, soil
• Vegetable matter (grass, seeds, pollen)
• Microscopic fragments of all types, bacteria, even odors

Note: "Microscopic evidence persists at the scene of a crime long after all the visible and obvious evidence has been removed and may solve the problem."

Importance (from Reddy's)

1. Often the decisive factor in determining guilt or innocence.
2. Can objectively supply demonstrable facts, resolving discrepancies in ordinary testimony.
3. Can be a material aid to link a suspect, a weapon, or a scene to a crime.
4. This is actual evidence, and its presence is absolute proof of the crime.

Reliability vs. Eyewitness Evidence

• Eyewitness evidence may be unreliable due to partisanship, faulty memory, or defective observation.
• Physical evidence cannot be wrong and cannot be completely absent.
• Only its interpretation can be incorrect - only human failure to find, study, and understand it can diminish its value.

Application at the Scene

• Evidence should be marked/labelled with date, time, place, from whom, and by whom it was taken.
• The chain of evidence must be intact and complete.
• Evidence should be preserved in the same condition in which it was found.
• Physical evidence can be obtained from: the scene of crime, the victim, the suspect, and the environment.