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Some important factors in forensics

WOUNDS: Sometimes, the presence of wounds on the body may assist in connecting a suspected criminal with a given crime, e.g. a piece of skin adherent to a window glass may correspond with the wound on the thief, or rupture of fraenum of penis may be present in a person accused of rape. Dust, sand, etc., may be recovered from wounds and identified.

DISEASE: The finding of disease, e.g. gallstones, renal stones, calcified leiomyomata, silicosis, asbestosis and congenital anomalies like horseshoe kidney, are helpful. The unidentified body should be checked for amputations, body deformities, pace-makers, implanted heart valves, enlarged joints of the fingers due to arthritis, immovable joints due to disease, bowed-legs and curvature of the spine.

X-rays will show the presence of healed fractures, metal pins, plates, or screw used in treating fractures. Commonly found missing organs at autopsy are tonsils, appendix, gallbladder, kidney, prostate, uterus and ovaries. Surgical scars may indicate hernia repair, circumcision or an operation upon the thyroid gland.

STAINS: Stains found on body or clothing of the accused and the victim may be the same and may be derived from the walls , doors, furniture, etc., at the scene of crime.

OCCUPATION MARKS:

(1) RECENT AND TEMPORARY: They include paint spots on painters, grease on engineers and mechanics, flour on bakers and millers, dyes on dye workers, etc. The microscopical examination of dust and debris on clothing, in the pockets and trouser turn-ups, under the fingernails and in the ear wax, is important in identification of unknown bodies. They may also connect the body with a specific place where a crime was committed.

(2) PERMANENT: Thickening of the palmar skin of fingers are seen on the right hands of butchers. Cuts, scars, callosities and hyperkeratosis of the hands indicate manual laborers. Tailors have marks of needle punctures on their left index finger. Coal miners have multiple ‘blue scars’ on the face and arms due to coal-dust contamination of small lacerations. Blacksmiths have scars on the back of the hand caused by burns from hot fragments.

Opticians have small cuts on the tips of index finger and thumb. Workers in chemicals and photography usually have discolored, distorted fingernails. Carpenters have callosities on the thumb and index finger, on the palms, and one shoulder is usually higher than the other. Bricklayers have a flattening of the thumb and index finger of the left hand due to constant picking up of bricks. The violinist has hardened tips on the fingers of the left hand.

COMPLEXION AND FEATURES: The complexion may be fair, wheat-colored, dark, brown, pale-brown or pale-yellow. Details of the features regarding eyes, nose, ears, lips, chin, and teeth should be noted. The face may be oval, round, square or long, and eyes may be black, grey, blue or brown. The features may change considerably from disease or even from worries of a long duration. Few persons can cleverly alter their features by changing the expression of their face. Expression is altered after death.

EYES: MEDICO-LEGAL IMPORTANCE:

(1)Identification: artificial eyes, absence of one or both eyes, shape, color of iris, setting: deep set, bulging or prominent, squint, nystagmus and cataract

The look of the person will show whether he is conscious, unconscious, frightened, confused, etc.

(2) ASPHYXIA: proptosis, congestion and petechial haemorrhages

(3) INJURIES :

  • Black eye (contusion of lids),
  • In fracture of anterior cranial fossa involving orbits, there may be effusion of blood into the orbits, proptosis, limitation of movement of eyeball and subconjunctival hemorrhage,
  • gouging of eyes,
  • lacerated wounds,
  • penetrating wounds,
  • foreign bodies,
  • chemical burns,
  • ulceration and opacity of cornea,
  • vitreous hemorrhages are likely to affect vision,
  • rupture of choroid and retina,
  • subluxation of lens and post- traumatic cataract.

(4) Poisoning:

  • Dilated pupils: datura, atropine, belladonna, cannabis, cocaine, alcohol, ergot, endrin, calotropis, strychnine, oleanders, HCN antihistamines, cyclic antidepressants, amphetamines.
  • Contracted pupils: opium, phenol, organophosphorus compounds, physostigmine, neostigmine, pilocarpine, strophanthin, nicotine, carbamates, barbiturates, benzodiazipines, caffeine, muscarine.
  • Alternate contraction and dilation: aconite.
  • Large and fixed: anticholenergic drugs, anoxia.
  • Small and fixed: opioids, cholinergic drugs.
  • Variable size and fixed: barbiturates, glutethimide, hypothermia.
  • Nystagmus: ethanol, ph en yt oin, c arb amaze pine, barbiturates, benzodiazipines, phencyclidine.

(5) NATURAL DISEASE: Blue sclerotics of osteogenesis imperfecta and odontogenesis imperfecta.

(6) ACUITY OF VISION: for crimes committed during night.

(7) WORKMEN’S COMPENSATION ACT.

CLOTHES AND ORNAMENTS: The clothing may indicate the social status to a certain extent from the texture and value. Any variety of uniform is very valuable for identification. Clothing may also indicate the occupation. The examination of clothing and personal effects is helpful in the identification of victims in mass disasters, such as fires, explosions and aircraft crashes. A detailed description of the size, color, condition and type of each garment and a record of laundry marks4 name tags and labels of tailors should be given.

Photographs and examination for invisible laundry marks by ultraviolet light are useful. The clothing may contain keys, letters, bank books, visiting cards, licenses or other documents which may give a clue to the name and address of the individual. Other personal effects like watches, rings, keys, belt buckles, etc., may be engraved with initials, names or dates. Eyeglasses may also be helpful. Bullet holes, tears, cuts or Tyre marks found on clothing may give information regarding the cause and manner of death.

The design of the ornaments varies from region to region. General cleanliness of the person and the state of the teeth, hands and feet give some idea of social status. If shoes are worn, the epidermis of the soles of the feet is thin and smooth without any fissures and cracks. A criminal may interchange his identity with that of another person by clothing and personal effects.

HANDWRITING (Calligraphy): Handwriting is characteristic of the individual, especially if it is written rapidly, but it may be disguised or forged. Mental and nervous disease and rheumatism alter the character. Evidence of handwriting experts is not conclusive, because it is opinion evidence.

SPEECH AND VOICE: Certain peculiarities of speech, e.g., stammering, stuttering, lisping and nasal twang become more evident when the individual is talking excitedly. Speech is also affected by nervous disease. To recognize a person from the voice is risky. It is possible for a person to alter his voice at will. Tape recording is useful.

No two voices are really alike. All the frequencies produced by the utterance of a single syllable can be plotted on a time baseline, which gives an acoustic “Spectrogram”, characteristic of the speaker. This is helpful in trapping anonymous telephone callers.

GAIT: Any identification based on recollection of physical characteristics (lameness, particular body postures or movements) of person in question by friends and relatives is unreliable. The gait may be altered by an accident or by design.

TRICKS OF MANNER AND HABIT: They are frequently hereditary, e.g., left-handedness. Jerky movement of shoulders or muscles of face is an individual characteristic.

MEMORY AND EDUCATION: They are sometimes useful, especially in cases of imposture.

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