Chapter 11: Forensic Identity
Identification of a person is vital among the living and the dead. In civil and criminal courts, results of trials often depend upon establishing proper identity.
Identity — The recognition of the individuality of a person, live or dead.
Identification of the Living
It becomes required when a person who has no relatives or acquaintances nearby and no documentary proof of identity is unable to provide such proof due to weakness, disease, mental instability, immaturity, infancy, unconsciousness, or real forgetfulness.
Identification of the Dead
Identification of the victim is hence a major step towards identification of the culprit responsible for the death.
Pedigree — A method of establishing the identity of the criminal involved in a crime in a police station.
Complete or Absolute Identity: Here the exact fixation of individuality of the person, alive or dead, is possible.
Partial or Incomplete Identity: Here the exact fixation of individuality is not possible, but identity to the extent of certain facts about the person is only possible.
Legal Identity: Here the exact fixation of the individuality is impossible, because he or she has been unknown to the people around.
Corpus Delicti — facts of any pre-defined criminal offense.
The main fact of corpus delicti is the establishment of identity of the dead body, infliction of violence in a particular way, at a particular time and place, by the person or people charged with the crime and none other.
The identification of a dead body and proof of corpus delicti is essential prior to passing sentence in murder trials.
Age
Sex
Other factors:
Race and religion/ communal characters
Stature and general development
Hairs
Complexion
Features
Deformities
Tattoo marks
Moles
Scars
Occupational stigmata
Dactylography
Poroscopy
Footprint
Lip prints
Palato prints
Ear prints
Anthropometry
Superimposition
Personal belongings
DNA fingerprinting
Brain fingerprints
Trace evidence factors
The age of a fetus during IUL can be assessed by studying the developmental morphology, appearance of ossification centers in skeletal bones, and also germination of teeth.
Haase’s Rule: This enables the estimation of the age of the fetus in lunar months from the crown-heel length (in cm) of the fetus.
Deciduous dentition — teeth present during early part of life, i.e. in childhood and they are totally 20 in number and begin to erupt at sixth month after birth and begin to shed off by sixth year. The tooth distribution in each jaw is as follows:
4 incisors
2 canines
4 molars
Each jaw has 10 teeth
Permanent dentition — teeth present during life, which begin to erupt from the sixth year of age and remain throughout the life. They are 32 in total.
Successional Teeth: The 4 incisors, 2 canines, and 4 premolars; which they erupt in predecessor deciduous teeth, with 4 premolars erupt in place of 4 temporary molars.
Superadded Teeth: The 6 molars, wherein they erupt independently without any predecessor teeth.
Each jaw has 16 teeth.
Other Factors about Teeth in Determining Age
Degree and extent of calcification of roots of teeth — ascertained by X-ray examination.
Attrition of teeth — wearing off the teeth on the grinding surface begins in the molars after middle age.
Old age — all teeth are lost and individual becomes edentulous.
Teeth | Temporary (months) | Permanent (years) |
---|---|---|
Central Incisor (Lower) | 06—08 | 07—08 |
Central Incisor (Upper) | 07—09 | 07—09 |
Lateral Incisor (Lower) | 07—09 | 07—09 |
Lateral Incisor (Upper) | 10—12 | 08—09 |
Canine | 18—20 | 11—12 |
First Premolar | Absent | 09—11 |
Second Premolar | Absent | 10—12 |
First Molar | 12—14 | 06—07 |
Second Molar | 20—30 | 12—14 |
Third Molar | Absent | 17—25 |
Characteristics | Deciduous Teeth | Permanent Teeth |
---|---|---|
Size | Smaller | Larger |
Color | Porcelain white | Ivory White |
Constriction at the crown-root junction | More prominent | Less prominent |
Edge | Sharp | Mamelons (Serrated) |
Cusp | Few and small | More in Number and well developed |
Gustafson described a method wherein various criteria of normal physiological changes in a tooth other than dental eruption order are considered in determining the age of a person.
If the eruption order of teeth could help determine the age up to 25 years, Gustafson’s method is helpful in determining the ages beyond 25 years.
Age by cross striations of incremental lines in the tooth enamel: The age of a person can be determined by counting the number of lines from the neonatal line onwards.
Age by cemental annulations: These are alternating light and dark lines visible under light microscopy of ground section of human tooth root cementum, are believed to be incremental lines and repeat an annual rhythm.
Age by racemization ratio (D/L ratio): Here accurate age (± 4 years) estimation is described by the dentin of the teeth using the racemization ratio of aspartic acid.
Changed Assessed | Descriptions |
---|---|
Attrition | Wearing down of incisal or occlusal surface due to mastication. |
Periodontosis | Retraction of gum margin and loosening of the tooth. |
Secondary Dentin | Seen within pulp cavity, due to aging/reaction to caries and periodontosis. |
Cementum Apposition | At and around root of tooth. |
Root Resorption | Involves both cementum and dentin. |
Root Transparency | Is best seen on ground section of tooth. |
Skull comprises two parts:
Bones of the calvaria are 8 in number, and they are: 2 parietal, one frontal, 2 temporal, one occipital, one sphenoid, and one ethmoid.
Bones of the face and jaws are 14 in number: 2 maxilla, 2 zygoma, 2 nasal, 2 lacrimal, 2 palatine, 2 inferior nasal concha, one mandible and one vomer.
Lateral and occipital fontanelle usually close within the first two months of birth.
The anterior fontanella along with two halves of mandible closes at the second year.
The condylar portion of occipital bone fuses with the squama at the third year and with the basi-occipital at the fifth year.
The metopic suture closes at about the third year, but in 5-10 per cent cases it persists and the condition is called metopism.
The basi-occipit fuses with the basi-sphenoid at about 18-21 years.
In the vault of the skull, closure of the sutures begins on the inner side 5-10 years earlier than on the outer side.
The coronal, sagittal, and lambdoid sutures start to close on their inner side at the age of about 25 years.
On the outer side, fusion occurs in the following order:
posterior one-third of sagittal suture at about 30-40 years;
anterior one-third of the sagittal and lower half of the coronal at about 40-50 years; and
middle sagittal and upper half of coronal at about 50- 60 years.
The lambdoid suture starts closing near the lambda and the union is often completed at about 45 years.
The squamous part of temporal bone usually fuses with neighbor by the age of 60 years.
Suture closure in skull occurs later in females than in males.
For age estimation sagittal suture is the most reliable, followed by lambdoid and coronal sutures in order of frequency.
A lateral head X-ray film is preferable for the study of coronal and lambdoid sutures.
Ectocranial suture closure is very variable. Sometimes, there may not be ectocranial suture closure. This is called lapsed union. This occurs most often in the sagittal suture.
Human skeleton is comprised of 206 bones.
Total number of bones in adult human skeleton:
Skull with mandible: 29 bones
Vertebral column: 26 bones
Thoracic Cage: 25 bones
Upper Limb: 64 bones
Lower Limb: 62 bones
Disappearance of skull sutures — after 60 years.
Attrition or loss of teeth — after 50 years.
Union of Xiphoid process with body of sternum — after 40 years.
Lipping of lumbar vertebra or bones of the joints of the extremities — after 45 years.
Union of greater cornu of hyoid bone with body.
Rarefaction of bone — after 60 years.
Age by changes in the articular surface of the pubic symphysis.
Calcification of costal (30 years) and laryngeal cartilage (50±12.7 years).
A radiograph best confirms ossification pattern or union of ossification centers in a bone.
Age Group | Radiograph Recommended |
---|---|
Infancy and Childhood | Wrist and Elbow |
Adolescence Age | Pelvis, hip and shoulder |
Adulthood | Elbow and Knee |
Old Age | Skull |
All Age Groups | Pelvis, hip |
Sacrum: It becomes a single bone at 21-25 years of age, leaving a gap between S1 and S2, until 32 years due to ‘lapsed union’.
Vertebrae: The feature increases in prominence up to the age of ten, and then gradually fades between 21 and 25 years. Later on, due to osteoarthritic changes in the form of lipping of vertebrae are seen after the age of 45 years.
Pubic hair:
They appear at the age of about 13 years in female and at the age of 14 years in male.
They are sparse, soft and light in color initially and later on turn thick, bushy and dark within 2 years of appearance with the onset of puberty.
Axillary hair: They appear at the age of about 14 years in female and at the age of 15 years in male.
Beard and moustache/facial hair: They appear only in male by 16 to 18 years.
Breasts: Begin to appear by 13 to 14 years in females only.
Voice: It become hoarse in males by 16 to 18 years.
Scalp hair: Begins to turn gray by 40 years. Also becomes less dense as the age advances.
Axillary and pubic hair Turn gray only at advanced old age.
Arcus senilis: This is a whitish ring that makes its appearance in the periphery of the cornea of the eyes due to the degenerative changes and begins at about the age of 40 years, is a normal process of aging.
Cataract in the eyes: It is seen in old age (>60s).
Wrinkles over the face: Are seen in old age (>60s).
Unless the age of a person determines the identity of the person, live or dead stands incomplete.
Embryo: When ovum getting impregnated in the uterus on the 7th day of fertilization; and the woman is said to be “pregnant.“
Fetus: The embryo from the 2nd lunar month.
Feticide: Killing of a fetus.
Viable Child: The fetus after the 7 calendar months of pregnancy and it can live independently if born.
Full-Term Fetus: Fetus after 10 lunar months of pregnancy.
Medical termination of pregnancy (MTP)-induction: A decision by one doctor is allowed up to 3 lunar months of pregnancy and beyond this period decision is always by two doctors.
Still-Born: Fetus after 28 weeks of IUL shows no signs of life or any breathing.
Infanticide — deliberate and unlawful killing of a newborn or a child below the age of 1 year by the act of omission or commission; killing of the viable child.
Marriage — Any matrimonial alliance entered into by a boy below 21 years and girl below 18 years will be invalid.
Rape: Sexual intercourse with a girl below 16 years, even with her consent, legally constitutes rape.
Majority: A person attains majority on completion of 18 years. He or she can cast a vote in general elections, sell or buy property or make a valid will and serve on jury only if sound mentally.
Age and child employment: A child below 14 years cannot be employed in a factory or in any other hazardous employment.
Consent: A child below 12 years cannot give consent for physical examination and the valid consent is to be given by the parents/guardian.
This includes traits establishing sex identity of an individual.
This constitutes anatomical sex component that determines sex and comprise of external appearances inclusive of external genitalia in male and female and internal genital tract in the female.
Traits | Male | Female |
---|---|---|
Testes | Present | Absent |
Penis | Present | Absent |
Ovary | Absent | Present |
Uterus | Absent | Present |
Vagina | Absent | Present |
Shoulder | Broader than hips | Narrower than hips |
Gluteal Region | Flat | Full and Rounded |
Adam’s apple | Prominent | Less Prominet |
Breasts | Absent | Grows at Puberty |
Pubic Hairs | Thick and extends to umbilicus only. | Thin and covers up only the mons pubis. |
Gonadal biopsy is a confirmatory method of determining sexual identity histologically.
A chromosome that determines whether an individual is male or female represents sex chromosome. This constitutes chromosomal sex or nuclear sex component in determining the sex.
In humans the sex chromosomes comprise just one pair of the total of 23 pairs of chromosomes.
The other 22 pairs of chromosomes are called autosomes.
The individual having two X-chromosomes (XX) is female, while the individual having one X and one Y-chromosome (XY) is male.
The X-chromosome in a female is seen in the form of chromatin condensation towards the nuclear membrane microscopically in the nucleus of a cell.
Barr body— the inactive X-chromosome in the somatic cells of mammalian females.
Buccal Smear — a test where cells are taken from the cheek. Cells are collected by scraping the cheek with a cotton swab. The cells can be used for genetic testing, as well as evaluated for the presence of Barr bodies (a mass seen in a normal female sex chromosome).
Vaginal Epithelium — the inner lining of the vagina consisting of multiple layers of (squamous) cells.
The basal membrane provides the support for the first layer of the epithelium-the basal layer.
The intermediate layers lie upon the basal layer, and the superficial layer is the outermost layer of the epithelium.
Pap test (or Pap smear) — looks for precancers, cell changes on the cervix that might become cervical cancer if they are not treated appropriately.
Peripheral blood smear test — a technique healthcare providers use to examine your red and white blood cells and your platelets.
This test gives them a clear picture of changes in your blood cells and platelets that may be a sign of disease.
Costal Cartilage Calcification Pattern: In this methodology radiological appearance of the calcification pattern of costal cartilage (5-12th rib) is considered in determining the sex in age group 16 to 20 years.
Footprint Ratio (FPR)
This is the ratio between maximum width (MW) and maximum length (ML) of the footprint in millimeters and is reported to be useful in establishing sexual identity of a person alive or dead.
Footprint ratio (FPR) value being derived using this formula is then compared with standard footprint ratio (SFPR) value.
FPR = Maximum Width of Footprint / Maximum Length of the Footprint
Mandibular canine index (MCI) is a ratio of maximum width of the permanent mandibular canine (mesiodistal crown width) to arch width.
Cytogenetics and DNA Analysis — powerful tool in sexing which can replace all older techniques in future.
Counting of Sex Material within the Nucleus: Stained with a fluorescent dye and viewed with U-V light, performed on the neurons in a brain smear or on cells from the kidneys.
Meticulous Autopsy Examination of Internal Genital Tract
Due to presence of intact external and internal genital system in a recently dead body, it may not be difficult to establish sexual identity.
Presence of uterus and appendages in a nulliparous woman and prostate in a man can confirm the sex of an individual, even in a highly decomposed cadaver.
Skeletal Examination
Skeletal remains or bones are also helpful in establishing sexual identity.
Sexing the skeleton, which is intact and entire, is certainly easier as against only a part of the skeleton that is available.
Concealed Sex: Criminals may try to conceal their sex to avoid detection by police by changing dress and other means.
Intersex — intermingling of sexual characteristics of either sex in one individual to a varying degree, including the physical form, reproductive organs and sex behavior.
Gonadal agenesis: In gonadal agenesis testes and ovary have never developed. Nuclear sex is negative.
Gonadal dysgenesis: In gonadal dysgenesis, the external sexual structures are present, but at puberty the testes/ovaries fail to develop.
Klinefelter’s syndrome: Anatomically malebut nuclear sex is female. Sex chromosome pattern is XXY (47 chromosomes).
Turner’s syndrome: Anatomically female, but the nuclear sex is male. Sex chromosome pattern XO (45 chromosomes).
True hermaphrodites: This is a condition of bisexuality. Here both ovary and testis (ovotestis) with external genitalia of both sexes exist in one individual.
Bilateral true hermaphroditism: There is a testis and an ovary (ovotestis) on each side.
Unilateral true hermaphroditism: There is a testis and an ovary (ovotestis) on one side and either a testis/an ovary on the other side.
Alternating true hermaphroditism: There is testis on one side and the ovary on the other side.
Pseudohermaphrodite:
Female pseudohermaphroditism has male external features, but internally has the female gonads.
Male pseudohermaphroditism has female external features, but internally has the male gonads.
Hormonal intersex: In a female pseudohermaphrodite, an excess production of androgenic hormone by adrenal cortical hyperplasia can modify the external genitalia of a genetic female.
Hypertrophy of the phallus, fusion of the labia majora and hirsutism may cause the parents to consider their child to be a male.
Psychological sex: Many men and women are psychologically dominated towards sexual inversion, a persistence of the childhood tendency.
Environment and upbringing: This decides the sex of rearing.
Increase in mass disasters often utilises race and racial characteristics in establishing the identity of victims.
As per Blueman Backs classification there are five human races on the basis of skin colour, and they are:
Caucasian (white)
Mongoloid (yellow)
Ethiopian (black)
American (red)
Malayan (brown).
Race determination usually depends on following:
Morphological characteristics/traits
Osteometric parameters: Osteometry in anthropological sciences comprise measurements of different bones in the body, assessing its proportionalities to each other and multivariate discriminate functional analysis.
Cephalic index (CI) — the ratio between breadth and length of the skull.
Vedic religion gave rise to what is now the oldest extant and World’s third-largest religion, Hinduism; the Abrahamic religions of Islam and Christianity, spread by missionary activity and conquest over many centuries, are the two other largest non-native religions.
Rest of the smaller groups of religions existing in India are: Sikhism, Buddhism, Jainism, Zoroastrianism and Judaism.
A typical Hindu male will wear dhoti, kurta as traditional dress.
Among the Hindus, in certain community namely Brahmins will have a total shaved scalp except a tuft of hairs grown long on the occipital protuberance region.
These individuals may paint a tilakum/vibhooti on the forehead and other parts of the body also such as front of the trunk, side of upper arms, forearms, front of neck etc, made up of sandalwood paste/vermilion/turmeric.
They may also wear a sacred thread which is a big loop of thread made up of six strands, worn on the chest across the left shoulder; a necklace of Rudraksham beads worn around the neck.
A typical Hindu female will wear a sari and choli, etc.
Married women will usually wear a beaded necklace made up of red corals and black beads and a thread (Mangolasutra/Tali) with application of vermillion (Kumkum) over the forehead on the hair partition/hairline.
They may also wear a nose stud made up of diamond/white stone on the left ala and silver toe rings on the second toe of both feet.
A typical Muslim male will wear pyjama and salwar.
Most of them will have a tapering beard.
It is customary/traditional for a male Muslim to submit himself for circumcision of the penis as early as 5-7 years.
There will be callosities over the forehead, and lateral malleolus of the left leg due to the particular position opted during the practicing of prayers—Namaz.
A typical Muslim female will wear a shalwar and kameez, etc. with a black gown (Burkha) covering completely, hiding the person from head to toes, except over eyes.
They will wear multiple nose and ear rings; will thus have their nose pierced over the ala as well as the nasal septum and on the margins of the helix and lobule of both ears.
Nationality and Language: Characteristics representing nationality of a person and language spoken may also help in establishing the identity of a person.
The type of dress worn, articles preserved in the pockets and wallets, passport, a tattoo mark/words inscribed, etc may reveal the nationality and language spoken.
In a living person talking to him/her can easily express the language identity.
Criminal identification by means of fingerprints is one of the most potent factors in apprehending fugitives who might otherwise escape arrest and continue their criminal activities indefinitely.
This type of identification also makes possible an accurate determination of the number of previous arrests and convictions, which results in the imposition of more equitable sentences by the judiciary.
Finger-print identification — the method of identification using the impressions made by the minute ridge formations or patterns found on the fingertips.
The friction skin of the palms and soles differs significantly from the skin covering the rest of the body as follows:
It is hairless and with no oil glands or any pigments.
This friction skin also has higher concentration of sweat glands, and these accrine sweat glands contribute mainly to the fingerprint residues.
Loop — usually begins on one side of the finger and ends on the same side. When this happens from the ulnar side it is called the ulnar loop and if on the radial side — radial loop.
Whorl: This could be having multiple circular/oval ridges, one around the other, or a single ridge, round in multiple rounds.
Arches:
Plain arch — when it is wave-like.
Tented arch — when the arch is sharp and spike-like.
Composite — It is a combination of more than one pattern, either a combination of arch, whorl and loop, or two different patterns: two whorls and arch or loop.
Accidental variety — no specific ridge pattern is available.
Central pocket loop: Here, surrounding the central circular/ oval ridge, there are other ridges which take a loop like course.
Type line: In loops and whorls, the ridges in the middle/ main part are surrounded by divergent ridges.
Delta: In loops and whorls, the point of the outermost ridges nearest to the damaged type line. Arches have no delta.
Core: In loops and whorls, the apparent central point of the ridge pattern.
Wash the finger properly with soap and water.
Ink the ball of the finger with printer’s ink.
Use an unglazed white paper.
Take finger-print in two different types:
Plain fingerprint by just pressing the inked ball of the finger on the paper.
Rolled fingerprint by pressing the inked finger ball, roll it from one side to the other side of the finger.
Epidermal ridges in the skin of palms and soles are developed as early as the 4th month of IUL.
Finger-print is a 100% accurate method in establishing identity. No fingerprints of 2 individuals, even in case of monozygus identical twins are similar.
Visible fingerprints: Fingers when smeared with blood, grease, etc. will leave their prints/impression on the weapon used for the crime/ furniture or such other articles that may be touched by criminal at the scene of crime unintentionally and can give clue for identifying the criminals.
Latent fingerprints (invisible fingerprints): Finger-print experts can render a faint and invisible/latent finger-print visible by special techniques using some developing agents, which are chemical powders and liquids.
Plastic fingerprints: These are prints of the finger left on soft materials such as wax, soap, dust, etc.
Fingerprints from dead body: Tip of the finger may get shriveled in a dead body and then may mask the picture.
Fingerprints are important because they can be transmitted easily from one place to another by telegraphic message easily.
FINDER-II — FINgerprint reaDER; can read the data about fingerprints such as ridges, bending, ridge bifurcation, image direction of fingerprints, etc.
In the FINDER-II system only 8 fingerprints are taken into consideration, excluding the little finger.
Poroscopy — study of fingerprints described by Locard providing absolute identity.
The papillary ridges of the skin of the finger balls and hands will have plenty of minute pores, which are the openings of sweat glands.
These pores are permanent and vary in shape, size, position and numbers over a given length of a ridge in each person, rendering them ideal factors for establishing identity.
When the finger-prints available are only a fragment and not complete.
The skin pattern of toes and heels from the sole of the feet are distinctive and permanent-can tell identity.
It is taken by using printer’s ink and a clean paper.
Spray the impression in the soil or sand with 80% of alcohol solution of Shellac. This hardens the soil or sand.
Next, smear the hardened surface with lubricant or dust with French chalk.
Then, pour an aqueous mixture of plaster of Paris and allow it to dry and on drying remove the cast and study the impression.
Footprint will be larger on walking than on standing.
Imprints left on soft and loose material like sand will always be smaller.
Look for any deformities like — flat foot, webfoot, supernumerary toes, loss of toes, etc.
The footprint of Newborn Infants: Usually taken in certain maternity hospitals for the simple reasons that foot-prints are very reliable means to identify newborn infants, if there is any mix-up of babies and mothers.
Body features also help one’s identity.
Color of iris of the eyes
Size and shape of ears and nose
Shape of the chin
Presence on the skin of:
A mole (nevus) which could be plain/hairy/big/small/tiny/ flat /raised and black/brown/red, etc.
A birthmark which could be an irregular colored patch on the skin.
Identikit — a powerful investigative tool that can create photorealistic facial composite sketches based on verbal description provided by a witness or victim about the criminal, which can help generate customized “wanted” posters.
Ear Prints: Shape, size, positioning, display, etc of the ears have been used to help in determination of human identity.
Broad, wing like soft/hard
Lobules of the ear may be wide and look freely hanging/ fixed to the face
Whole ear may be tending to come forward/backwards .
Ears may have hairs on the helix and tragus, seen only in male (linked to Y-chromosome).
Nose Prints: These are also chance prints, may be found at the crime scene on the mirror, corners of the walls, doors and so on. It may also be seen on the body of the victim/assistant.
The Roman nose: This type of nose is convex, like a hook. The word aquiline is derived from the Latin word ‘aquilinus’ which means ‘eagle like’.
The Greek nose: This type of nose is perfectly straight with no curves or hooked like shape.
The Nubian nose: This type of nose has wide nostrils. It is generally a little narrow at the top, thick and broad at the middle and wide at the end.
The Jewish or hawk nose: It is very convex, to the extent that it almost looks like a bow. It is very thin and sharp as well.
Snub nose: This type of nose is quite short and is neither sharp, nor hook-like nor wide. It is almost as short as a nose possibly can be.
The turn up nose: This type of nose is also called the celestial nose. It is so called because it runs continuously from the eyes towards the tip.
Palato Prints (Rugoscopy): Anterior part of the palate has rugae or grooves and ridges on either side of the midline which is considered to be individualistic and help establish identity.
Lip Prints (Cheiloscopy): It may be recovered on the wine bottles, glasses, on love letters/ notes, windows, doors, crockery items, cigarette buts etc.
Suzuki and Tsuchihastu coined the terminology figure linearum labiorum rubrorum for the grooves on the lip prints and classified them in to six types:
Type I — Clear-cut grooves running vertically over the lips
Type I1 — Partial length grooves of type of variety
Type II — Branched grooves
Type III — Intersected grooves
Type IV — Reticular
Type V — Other patterns
Electrocardiogram (ECG): It has been reported that the ECG pattern has unique, specific, individualistic characteristics which can help in establishing human identity.
Nail Prints: Ridges on the surface of the nails, their number, dimension of each ridge, their depressions and elevations, all in all are of help as unique factors in establishing human identity.
Hairs: When a material, alleged to be a hair is given for forensic examination, one may have to establish the following:
Confirm it as a hair
Confirm it as a human hair
Site of origin of hair
Injury to hair
Singed hair — peculiar hair showing changes in its morphology due to flame burns or fire arm injury.
Hair and stains on hair
Hair and identity
Hair and poisoning
Hair and miscellaneous information.
Characteristics | Human Hair | Animal Hair |
---|---|---|
Texture | Fine, thin | Coarse, thick |
Cuticular Scale Pattern | Small, flat, serrated | Large, polyhedral, wavy |
Medulla | Narrow | Wider |
Pigment | Cuticle | Medulla |
Precipitin Test | Positive | Negative |
Injury on the Hair | Type of Weapon/Injury |
---|---|
Cut end is clean, if seen fresh, but turns round in few days | Sharp Weapons |
Cut end is crushed out | Blunt Weapons |
Bulb is distorted, irregular and swollen, if seen fresh | Forcibly Plucked Hair |
Bulb atrophic small and shrunken off with smooth surface | Naturally shed hair |
Type of Stain | Medical Information Derived |
---|---|
Mud stain | Struggle |
Seminal stain | Rape/Sexual Offenses |
Blood stains | Trauma/Injury |
Salivary stains | Asphyxial death |
Carbon particles in stains | Burns/Firearm Injury |
Presence of dyes | Concealing the natural color or age identity. |
Stature is defined as the height of a person.
Stature and Diurnal variation of Stature
Stature is proved to be varying at different times of the day, ranging from 1.5 to 5 cm. Stature of person is said to be minimum in the afternoon and in the evening, while maximum in the morning, after sleep.
Factors Affecting Stature Variation
Death can bring about body lengthening by about 1.25 cm for a male and 2 cm for a female on an average.
Determination of Stature
The length between outstretched fingertips of 2 middle finger is equal to the height (stature)
Length of one arm × 2 + 30 cm for 2 clavicles + 4 cm for the sternum is equal to the height (stature)
Vertex to symphysis pubic length = 1⁄2 of the height (stature)
Sternal notch to symphysis pubic length × 3.3 is equal to height (stature)
Length of entire skeleton +2.5–4 cm (For the soft parts thickness) is equal to the height (stature).
Stature from Skeletal Remains
Karl Pearson’s formula
Trotter and Glaister’s formula
Factors Affecting Multiplication Factor (MF)
Sex: Varies in male and female
Age: Varies in adults and children
Bones: Varies from one long bone to another long bone
Type of bone: Varies for wet and dry bones
Race: Varies from race to race.
Congenital — e.g. cleft lip, hare lip, cleft palate, overriding teeth, improper teeth, protruding teeth, moles, birthmarks, super numerary finger/toes (polydactylia), flat feet, webbed feet, etc.
Moles — small dark spot on the skin can appear at birth or later, anywhere on the body, and can be of a variety of shapes and coloration.
Naevi — group of lesions where moles are part of.
Birthmark — represents accumulation of skin pigment locally, with overgrowth of vessels, or other confined abnormality of the skin.
Moles and birthmarks are of great importance in establishing identity of a person. For identification purpose, they are described in relation to a nearby anatomical landmark.
Removal of the mole: Techniques of removing the moles include laser treatment, electrocautery technique and surgery.
Mole removal surgery — a very simple method as it allows the surgeon to be sure to remove it as an outpatient procedure, where an anesthetic and a freezing solution is applied to the mole, and then shaved it away with a scalpel.
Laser treatment and electrocautery technique — are effective only on very flat moles which are on the surface of the skin are both effective only with superficial moles in the surface layers of the skin and not in the deeper parts of skin.
Birthmarks are usually painless and harmless, but some may cause complications, such as pressure on other organs, they may be linked with congenital diseases, or, rarely, may transform into a malignancy, which means it is better a birthmark be examined by a doctor.
Tattoo marks are fairly good identification marks, both for living and dead subjects. Imprinting pigments of different colors in the dermis by multiple puncture methods produces tattoo marks.
Carbon dust, Indian ink, indigo, Chinese black, Prussian blue, cinnabar, cobalt, vermilion, etc. Some of the chemicals contents of different color pigments used for tattooing are:
Red pigment – Mercury
Green pigment – Chromium
Yellow pigment – Cadmium
Blue pigment – Cobalt
Tattoo marks mostly represent personal details, details of the favorites, beloved, lover, friend, relatives, pets, place of living, religious beliefs, sexual fantasies, etc.
Alteration of a tattoo mark is possible. It can be done by over tattooing with titanium oxide or with white pigments.
Tattoo marks are fairly permanent, and stay life long if the pigments are placed in dermis and on the covered parts of the body.
Tattoo marks may be removed/eliminated. Certain methods by which the tattoos can be erased are enumerated below:
Surgical skin grafting (plastic surgery)
Local use of corrosive
Electrolysis which releases and dissolves the pigments to be washed out;
Applying carbon dioxide snow
Inflicting injury over the area or by dermabrasion
Application of caustic substances
Exposure to laser beams
Cryosurgery, etc.
Designs drawn can help establish the identification of race, nationality, occupation, religion, language, name of the person or his/her beloved ones, relatives, friends, etc.
The designs could be of an idol, obscene figure, a flower, etc. often represent the mental make up, desire, inclination, etc. of an individual
Identification by tattoos is possible even in a highly decomposed cadaver, as long as the dermis is intact.
Attempts for concealment of tattoo marks artificially is strongly suggestive of concealment of identity with a positive criminal background.
A tattoo at times may cause infection (even AIDS), sepsis, ulcer, keloid formation, etc.
Drug addicts may conceal the site of injection by a tattoo design.
Those who practice abnormal sex like homosexuals may tattoo a specific design to recognize each other.
Tattooing and firearm wounds: The unburned gunpowder may also cause tattooing or semi burnt gunpowder particles from a firearm discharge, around the wound of entry, and can give clues regarding the firearm injury and also the range of firing— involuntary tattoo marks.
Medical and practical applications of tattooing: Tattoos have a number of legitimate medical applications.
Nevi flemmi have been tattooed for camouflaging it, vitiligo patients can be tattooed to almost normal skin color.
Facial tattooing is the latest trend in cosmetic surgery.
Correctional tattooing is promoted to get permanent eyelashes and eyebrows etc tattooed in a required style. It has also been used to create nipple and areola after breast surgery.
Color defects in the lips after facial surgery can also be observed by tattooing.
Scar is a product of healing of a wound by fibrosis and cicatrization.
It is permanent and may change in its size during the growing ages, but its shape remains unchanged all throughout the life, if there is no keloid formation or any other interference, renders it an important means of establishing human identity.
Scars are permanent and they relatively do not change in their shape, position in relation to anatomical landmarks of the body; they can constitute an ideal factor for establishing the identity of a person.
A scar with keloid formation may not be of any help as an ideal entity for identification purposes.
Scar can also give clues regarding type of injury or blunt force trauma and thereby the type of weapon used, time since injury, causative weapon, etc.
The umbilicus: It is an iatrogenic/doctor given, permanent that has no medicolegal importance.
Strial albicantes are multiple parallel whitish lines on the lower abdomen of a woman who has undergone pregnancy and delivery.
Hypertrophic scars and keloids: Hypertrophic scars usually settle or begin to regress in 6 months.
Keloids may extend beyond the wound itself and continue to increase in size by 6 months.
Extensor surfaces, strong and burned skin are the commonest site of appearance.
Negroes and young people are more often affected.
A scar over the antecubital region or dorsum of hand may be a clue about drug addiction.
Striae gravidarum are scars of past pregnancy or tumor in the abdomen.
Scar on the victim may be claimed as that of an infected wound by the accused.
Scar may be changed surgically into different shape or completely erased by plastic surgery to avoid implication with a criminal offense.
An apparently invisible scar may be made visible by ultraviolet rays, by application of heat or rubbing.
A scar may be developed after the removal or erasure of a tattoo or destroy finger-prints to avoid identification.
Scars being less vascular and fibrous in nature can resist putrefaction and thus help in partial identification of the deceased.
Scar on the knees should not be considered for identification purpose as they are common in most of the people due to frequent injuring due to falls during the childhood
Anthropometry — science of measuring body parts.
It is assumed that after the age of 21 years the skeleton stops growing and hence the measurements of various parts of the body remain constant.
It is also assumed that no two people will have bones of identical dimensions.
Only applicable in adults
Errors in taking measurements by instruments.
Needs measurements of various parts of the body
This has been replaced by dactylography technique.
Large number of occupational stigmas can be of help broadly in determining the job of the deceased, and thereby be of great help to investigating agencies in narrowing down their investigation for identifying the unknown individual, have been described in literature.
Presence of grease, paint, dust, etc. on the body and garments worn can give clues regarding the occupation of a person and thereby establish partial identity of a person alive or dead.
Presence of grease — suggestive of mechanic
Presence of linear callosities on the fingers of the left hand — violinist, guitarist, etc.
Postural Trauma Callosities in Namazis over the bony areas of the body which are pressed against the ground during ‘namaz’ (prayer) have been described.
The degree of thickening or callositing may not be well appreciated in Namazis who use soft carpet flooring.
Presence of callosities on the toes.
If a photograph of a missing person (front profile) is available and the skull with mandible is both recovered, this technique may be used in ruling out that the skull belongs to the person in the photograph.
Enlarge the photograph to ‘life size’, the enlargement factor being based upon the measurements of the fabric of the deceased, or other measurable items seen in the photograph, or the focal length of camera lenses used, or the dimensions of the anterior teeth, etc.
The skull is adjusted in such a way that the inclination and orientation are same as that of the head in the photograph.
A life size picture is taken and superimposed on the transparency of life size antemortem photograph, making allowances for soft tissue and hair thickness.
The anatomical landmarks are then compared for a positive match.
Examine the following characteristics in the superimposed photograph:
Outlines of skull and mandible fit into the outlines of head and face in portrait.
Vault of the skull to hair line.
Eyes to orbits.
Nasion with origin of nose.
Nasal aperture with nose.
Nasal spine in centre which is little above the nose.
Prosthion in the central line.
Upper border of the upper jaw i.e. below the tip of the nose.
Teeth in relation to lips.
Zygoma over the highlights below the eyes.
Tip of the mandible (Gnathion) with chin.
Position and shape of upper jaw with general contour of cheeks.
Slight variations in magnification of antemortem photograph or slight change in angulations of the skull from that of photograph can lead to major discrepancies resulting in a mismatch.
The method is laborious and time consuming.
Step 1
The antemortem photograph, preferably with a smiling face exposing the teeth is now mounted close by.
A color video camera firmly mounted on a tripod is aligned at right angles to the antemortem photograph.
The center of the lens of this camera should be at the same level as the horizontal center of the photograph.
Step 2
The dry skull without any soft tissue/ any foreign matter on it is mounted on an adjustable support allowing movement in all the three planes.
Keep a contrasting background behind the skull.
Another color video camera is firmly mounted on a tripod in a same way as the previous.
Step 3
The video signals from both cameras are fed into a vision mixer so that a variety of functions like horizontal and vertical wiping, superimposition, and negative simulation can be performed.
The skull is oriented on the adjustable mount as closely as possible to the angulations of the head in photograph.
The video pictures from both cameras are relayed into the video mixer.
By adjusting the mixer, the video picture of photograph can be enlarged.
The video mixer will offer all flexibility here in making the adjustments and provides immediate results without having to process photographs or make tracings.
After correct enlargement and orientations, superimposition is done, and features are compared with respect to the landmarks.
Video mixer can help fading in and out of either pictures, or sweeping over each other in vertical or the horizontal plane.
The procedure allows even part of the skull or the photograph to be superimposed in either the vertical or horizontal plane on the video screen so that an accurate match is obtained.
The technique can be video taped. Taped material can be used for court purposes also.
The actual experiences of the perpetrator or witness are encoded in a very specific manner in his/her brain.
This would be revealed during the course of the Electroencephalogram (EEG) and the carefully formulated probes used to stimulate his brain waves.
Probes are the key words or phrases compiled with the help of the investigating officers, act as a trigger for the person under scrutiny.
Investigators may ride brain waves to nail the culprits.
In the polygraph (lie detector), the machine takes note of the subject’s suppression or anxiety in divulging information. But with the brain finger-printing we can go beyond that.
Ethical dilemma — the scientific research reports needs thinking about its ethics of any such a method.
When two objects collide or come in contact with each other, there is always transfer of materials from one object to the other.
A criminal who commits a crime often leaves some traces at the scene of crime or takes something away from the scene or from the victim.
The investigating officer has to play a vital role in this work, when the trace evidence materials are to be collected from scene of crime.
The forensic expert who has to play vital role in collecting trace evidence materials from a living individual or a dead body at mortuary.
Living person: Seminal stains in an alleged rape victim, blood stains of the victim on the body of the accused in an alleged assault, brought for medical examination.
Dead body: Salivary dribbling marks on the front of the dead body in a case of hanging which is suggestive of antemortem hanging.
Blood: It is the most important body fluid, which easily escapes during any assault, injury, murder, vehicular accident and sexual crimes.
Bloodstains: These are often present on the clothes, weapons, floor, furniture, wheels or part of a vehicle, at the scene of crime, on the victim or the assailant.
Whether the stain is blood or not: This can be decided by routine/screening and confirmatory tests.
Routine test:
Benzidine test: Here a negative test is of more importance as it rules out blood, but a positive test is not of significance as vegetable stain, pus, saliva, milk, rust, etc. stains can also give positive reaction with this test needing confirmatory test to prove blood.
Confirmatory tests include several testing:
Microchemical tests — based on the property of hem (iron) part of hemoglobin to form characteristic colored crystals with certain reagents, and these crystals can be seen only microscopically.
Microscopic examination — possible only with a fresh stain and one can clearly identify the RBCs and WBCs, which helps in confirming the stain as blood.
Spectroscopic examination — needs only a very small quantity of stain. This test depends on property of the translucent colored fluid to absorb certain rays from the solar spectrum.
Whether human or animal blood: This includes serological test namely precipitin test — this is a sensitive test based on an antigen-antibody reaction.
Blood group of the stain — According to the antigens present on the surface of red cell membrane, the blood can be classified into four major group: Group A, Group B, Group AB, and Group O.
Universal Donor — group O blood.
Universal recipient — group AB blood.
Sex of the bloodstain: determined by the examination of leukocytes. The neutrophil contains a drumstick nucleus in females only. This drumstick nucleus is known as Davidson’s body.
Age of the stain: Color and nature of the stain can help in establishing age of the stain as follows:
Blood when fresh is bright red in color.
In 24 hours—it is reddish brown.
More than 24 hours—it is dark brown and for a longer duration it becomes black.
If the stain is fresh—it is moist and sticky.
If the stain is old—it is dry and scaly.
Whether arterial or venues blood
If blood is of arterial origin—it is bright red.
If blood has venous origin—it is dark red.
Shape Of The Bloodstain And Opinions Derived
Circular marks — fall from short height.
Circular with irregular margins — fall from moderate height.
Needle-like projections at the margins — fall from a distant range of angles.
Arterial bleeding is in spurts and bright red in color
Venous bleeding is oozing and dark red in color.
Nasal bleeding — Blood mixed with nasal mucous and hair.
Stomach or gastric bleeding — Chocolate color due to the presence of acid, haematin and is acidic in reaction.
Menstrual bleeding — Dark colored fluid blood with foul smell and with endometrial debris, acidic reaction, vaginal epithelial cells and bacteria are present.
Abortion bleeding —Dark clotted blood. Endometrial and placental debris with fetal remnants sometimes present.
Antemortem bloodstains get broken into scales due to the presence of fibrin, whereas the postmortem bloodstains become powder.
The stains, which resemble bloodstains, are paint, iron rust, fruit and vegetable stains and synthetic dyes.
Semen and seminal stains:
The male at the climax of sexual intercourse ejaculates semen. About 2 to 5 ml is voided normally each time.
Semen — consists of sperms and seminal fluid, which is rich in sugars, proteins and enzymes.
In vasectomized and sterile persons, semen will not contain sperms.
Appearance: Semen and seminal stains has the following characteristics:
Freshly voided semen will be vicious, dirty white in color and will have a musty odor.
In white clothes, it produces a light yellow stain with a starchy feel on drying.
Uncolored clothes stains are visible only in ultraviolet light.
Saliva: It is the secretion from the salivary glands situated intra- and extraorally. The secretion flows through ducts from the glands opening into the mouth.
Composition of saliva:
Saliva consists of water, salts and various enzymes.
Amylase is the important enzyme present in saliva
Urine and urinary stains can be detected by chemical tests.
Grouping is also possible because urine contains group specific substances.
Feces and fecal stains can be identified by microscopic examination for the presence of undigested matter.
Feces contain stercobilin, which can be detected by chemical tests.
Grouping can be done using the absorption elution method.
Identification of a person is vital among the living and the dead. In civil and criminal courts, results of trials often depend upon establishing proper identity.
Identity — The recognition of the individuality of a person, live or dead.
Identification of the Living
It becomes required when a person who has no relatives or acquaintances nearby and no documentary proof of identity is unable to provide such proof due to weakness, disease, mental instability, immaturity, infancy, unconsciousness, or real forgetfulness.
Identification of the Dead
Identification of the victim is hence a major step towards identification of the culprit responsible for the death.
Pedigree — A method of establishing the identity of the criminal involved in a crime in a police station.
Complete or Absolute Identity: Here the exact fixation of individuality of the person, alive or dead, is possible.
Partial or Incomplete Identity: Here the exact fixation of individuality is not possible, but identity to the extent of certain facts about the person is only possible.
Legal Identity: Here the exact fixation of the individuality is impossible, because he or she has been unknown to the people around.
Corpus Delicti — facts of any pre-defined criminal offense.
The main fact of corpus delicti is the establishment of identity of the dead body, infliction of violence in a particular way, at a particular time and place, by the person or people charged with the crime and none other.
The identification of a dead body and proof of corpus delicti is essential prior to passing sentence in murder trials.
Age
Sex
Other factors:
Race and religion/ communal characters
Stature and general development
Hairs
Complexion
Features
Deformities
Tattoo marks
Moles
Scars
Occupational stigmata
Dactylography
Poroscopy
Footprint
Lip prints
Palato prints
Ear prints
Anthropometry
Superimposition
Personal belongings
DNA fingerprinting
Brain fingerprints
Trace evidence factors
The age of a fetus during IUL can be assessed by studying the developmental morphology, appearance of ossification centers in skeletal bones, and also germination of teeth.
Haase’s Rule: This enables the estimation of the age of the fetus in lunar months from the crown-heel length (in cm) of the fetus.
Deciduous dentition — teeth present during early part of life, i.e. in childhood and they are totally 20 in number and begin to erupt at sixth month after birth and begin to shed off by sixth year. The tooth distribution in each jaw is as follows:
4 incisors
2 canines
4 molars
Each jaw has 10 teeth
Permanent dentition — teeth present during life, which begin to erupt from the sixth year of age and remain throughout the life. They are 32 in total.
Successional Teeth: The 4 incisors, 2 canines, and 4 premolars; which they erupt in predecessor deciduous teeth, with 4 premolars erupt in place of 4 temporary molars.
Superadded Teeth: The 6 molars, wherein they erupt independently without any predecessor teeth.
Each jaw has 16 teeth.
Other Factors about Teeth in Determining Age
Degree and extent of calcification of roots of teeth — ascertained by X-ray examination.
Attrition of teeth — wearing off the teeth on the grinding surface begins in the molars after middle age.
Old age — all teeth are lost and individual becomes edentulous.
Teeth | Temporary (months) | Permanent (years) |
---|---|---|
Central Incisor (Lower) | 06—08 | 07—08 |
Central Incisor (Upper) | 07—09 | 07—09 |
Lateral Incisor (Lower) | 07—09 | 07—09 |
Lateral Incisor (Upper) | 10—12 | 08—09 |
Canine | 18—20 | 11—12 |
First Premolar | Absent | 09—11 |
Second Premolar | Absent | 10—12 |
First Molar | 12—14 | 06—07 |
Second Molar | 20—30 | 12—14 |
Third Molar | Absent | 17—25 |
Characteristics | Deciduous Teeth | Permanent Teeth |
---|---|---|
Size | Smaller | Larger |
Color | Porcelain white | Ivory White |
Constriction at the crown-root junction | More prominent | Less prominent |
Edge | Sharp | Mamelons (Serrated) |
Cusp | Few and small | More in Number and well developed |
Gustafson described a method wherein various criteria of normal physiological changes in a tooth other than dental eruption order are considered in determining the age of a person.
If the eruption order of teeth could help determine the age up to 25 years, Gustafson’s method is helpful in determining the ages beyond 25 years.
Age by cross striations of incremental lines in the tooth enamel: The age of a person can be determined by counting the number of lines from the neonatal line onwards.
Age by cemental annulations: These are alternating light and dark lines visible under light microscopy of ground section of human tooth root cementum, are believed to be incremental lines and repeat an annual rhythm.
Age by racemization ratio (D/L ratio): Here accurate age (± 4 years) estimation is described by the dentin of the teeth using the racemization ratio of aspartic acid.
Changed Assessed | Descriptions |
---|---|
Attrition | Wearing down of incisal or occlusal surface due to mastication. |
Periodontosis | Retraction of gum margin and loosening of the tooth. |
Secondary Dentin | Seen within pulp cavity, due to aging/reaction to caries and periodontosis. |
Cementum Apposition | At and around root of tooth. |
Root Resorption | Involves both cementum and dentin. |
Root Transparency | Is best seen on ground section of tooth. |
Skull comprises two parts:
Bones of the calvaria are 8 in number, and they are: 2 parietal, one frontal, 2 temporal, one occipital, one sphenoid, and one ethmoid.
Bones of the face and jaws are 14 in number: 2 maxilla, 2 zygoma, 2 nasal, 2 lacrimal, 2 palatine, 2 inferior nasal concha, one mandible and one vomer.
Lateral and occipital fontanelle usually close within the first two months of birth.
The anterior fontanella along with two halves of mandible closes at the second year.
The condylar portion of occipital bone fuses with the squama at the third year and with the basi-occipital at the fifth year.
The metopic suture closes at about the third year, but in 5-10 per cent cases it persists and the condition is called metopism.
The basi-occipit fuses with the basi-sphenoid at about 18-21 years.
In the vault of the skull, closure of the sutures begins on the inner side 5-10 years earlier than on the outer side.
The coronal, sagittal, and lambdoid sutures start to close on their inner side at the age of about 25 years.
On the outer side, fusion occurs in the following order:
posterior one-third of sagittal suture at about 30-40 years;
anterior one-third of the sagittal and lower half of the coronal at about 40-50 years; and
middle sagittal and upper half of coronal at about 50- 60 years.
The lambdoid suture starts closing near the lambda and the union is often completed at about 45 years.
The squamous part of temporal bone usually fuses with neighbor by the age of 60 years.
Suture closure in skull occurs later in females than in males.
For age estimation sagittal suture is the most reliable, followed by lambdoid and coronal sutures in order of frequency.
A lateral head X-ray film is preferable for the study of coronal and lambdoid sutures.
Ectocranial suture closure is very variable. Sometimes, there may not be ectocranial suture closure. This is called lapsed union. This occurs most often in the sagittal suture.
Human skeleton is comprised of 206 bones.
Total number of bones in adult human skeleton:
Skull with mandible: 29 bones
Vertebral column: 26 bones
Thoracic Cage: 25 bones
Upper Limb: 64 bones
Lower Limb: 62 bones
Disappearance of skull sutures — after 60 years.
Attrition or loss of teeth — after 50 years.
Union of Xiphoid process with body of sternum — after 40 years.
Lipping of lumbar vertebra or bones of the joints of the extremities — after 45 years.
Union of greater cornu of hyoid bone with body.
Rarefaction of bone — after 60 years.
Age by changes in the articular surface of the pubic symphysis.
Calcification of costal (30 years) and laryngeal cartilage (50±12.7 years).
A radiograph best confirms ossification pattern or union of ossification centers in a bone.
Age Group | Radiograph Recommended |
---|---|
Infancy and Childhood | Wrist and Elbow |
Adolescence Age | Pelvis, hip and shoulder |
Adulthood | Elbow and Knee |
Old Age | Skull |
All Age Groups | Pelvis, hip |
Sacrum: It becomes a single bone at 21-25 years of age, leaving a gap between S1 and S2, until 32 years due to ‘lapsed union’.
Vertebrae: The feature increases in prominence up to the age of ten, and then gradually fades between 21 and 25 years. Later on, due to osteoarthritic changes in the form of lipping of vertebrae are seen after the age of 45 years.
Pubic hair:
They appear at the age of about 13 years in female and at the age of 14 years in male.
They are sparse, soft and light in color initially and later on turn thick, bushy and dark within 2 years of appearance with the onset of puberty.
Axillary hair: They appear at the age of about 14 years in female and at the age of 15 years in male.
Beard and moustache/facial hair: They appear only in male by 16 to 18 years.
Breasts: Begin to appear by 13 to 14 years in females only.
Voice: It become hoarse in males by 16 to 18 years.
Scalp hair: Begins to turn gray by 40 years. Also becomes less dense as the age advances.
Axillary and pubic hair Turn gray only at advanced old age.
Arcus senilis: This is a whitish ring that makes its appearance in the periphery of the cornea of the eyes due to the degenerative changes and begins at about the age of 40 years, is a normal process of aging.
Cataract in the eyes: It is seen in old age (>60s).
Wrinkles over the face: Are seen in old age (>60s).
Unless the age of a person determines the identity of the person, live or dead stands incomplete.
Embryo: When ovum getting impregnated in the uterus on the 7th day of fertilization; and the woman is said to be “pregnant.“
Fetus: The embryo from the 2nd lunar month.
Feticide: Killing of a fetus.
Viable Child: The fetus after the 7 calendar months of pregnancy and it can live independently if born.
Full-Term Fetus: Fetus after 10 lunar months of pregnancy.
Medical termination of pregnancy (MTP)-induction: A decision by one doctor is allowed up to 3 lunar months of pregnancy and beyond this period decision is always by two doctors.
Still-Born: Fetus after 28 weeks of IUL shows no signs of life or any breathing.
Infanticide — deliberate and unlawful killing of a newborn or a child below the age of 1 year by the act of omission or commission; killing of the viable child.
Marriage — Any matrimonial alliance entered into by a boy below 21 years and girl below 18 years will be invalid.
Rape: Sexual intercourse with a girl below 16 years, even with her consent, legally constitutes rape.
Majority: A person attains majority on completion of 18 years. He or she can cast a vote in general elections, sell or buy property or make a valid will and serve on jury only if sound mentally.
Age and child employment: A child below 14 years cannot be employed in a factory or in any other hazardous employment.
Consent: A child below 12 years cannot give consent for physical examination and the valid consent is to be given by the parents/guardian.
This includes traits establishing sex identity of an individual.
This constitutes anatomical sex component that determines sex and comprise of external appearances inclusive of external genitalia in male and female and internal genital tract in the female.
Traits | Male | Female |
---|---|---|
Testes | Present | Absent |
Penis | Present | Absent |
Ovary | Absent | Present |
Uterus | Absent | Present |
Vagina | Absent | Present |
Shoulder | Broader than hips | Narrower than hips |
Gluteal Region | Flat | Full and Rounded |
Adam’s apple | Prominent | Less Prominet |
Breasts | Absent | Grows at Puberty |
Pubic Hairs | Thick and extends to umbilicus only. | Thin and covers up only the mons pubis. |
Gonadal biopsy is a confirmatory method of determining sexual identity histologically.
A chromosome that determines whether an individual is male or female represents sex chromosome. This constitutes chromosomal sex or nuclear sex component in determining the sex.
In humans the sex chromosomes comprise just one pair of the total of 23 pairs of chromosomes.
The other 22 pairs of chromosomes are called autosomes.
The individual having two X-chromosomes (XX) is female, while the individual having one X and one Y-chromosome (XY) is male.
The X-chromosome in a female is seen in the form of chromatin condensation towards the nuclear membrane microscopically in the nucleus of a cell.
Barr body— the inactive X-chromosome in the somatic cells of mammalian females.
Buccal Smear — a test where cells are taken from the cheek. Cells are collected by scraping the cheek with a cotton swab. The cells can be used for genetic testing, as well as evaluated for the presence of Barr bodies (a mass seen in a normal female sex chromosome).
Vaginal Epithelium — the inner lining of the vagina consisting of multiple layers of (squamous) cells.
The basal membrane provides the support for the first layer of the epithelium-the basal layer.
The intermediate layers lie upon the basal layer, and the superficial layer is the outermost layer of the epithelium.
Pap test (or Pap smear) — looks for precancers, cell changes on the cervix that might become cervical cancer if they are not treated appropriately.
Peripheral blood smear test — a technique healthcare providers use to examine your red and white blood cells and your platelets.
This test gives them a clear picture of changes in your blood cells and platelets that may be a sign of disease.
Costal Cartilage Calcification Pattern: In this methodology radiological appearance of the calcification pattern of costal cartilage (5-12th rib) is considered in determining the sex in age group 16 to 20 years.
Footprint Ratio (FPR)
This is the ratio between maximum width (MW) and maximum length (ML) of the footprint in millimeters and is reported to be useful in establishing sexual identity of a person alive or dead.
Footprint ratio (FPR) value being derived using this formula is then compared with standard footprint ratio (SFPR) value.
FPR = Maximum Width of Footprint / Maximum Length of the Footprint
Mandibular canine index (MCI) is a ratio of maximum width of the permanent mandibular canine (mesiodistal crown width) to arch width.
Cytogenetics and DNA Analysis — powerful tool in sexing which can replace all older techniques in future.
Counting of Sex Material within the Nucleus: Stained with a fluorescent dye and viewed with U-V light, performed on the neurons in a brain smear or on cells from the kidneys.
Meticulous Autopsy Examination of Internal Genital Tract
Due to presence of intact external and internal genital system in a recently dead body, it may not be difficult to establish sexual identity.
Presence of uterus and appendages in a nulliparous woman and prostate in a man can confirm the sex of an individual, even in a highly decomposed cadaver.
Skeletal Examination
Skeletal remains or bones are also helpful in establishing sexual identity.
Sexing the skeleton, which is intact and entire, is certainly easier as against only a part of the skeleton that is available.
Concealed Sex: Criminals may try to conceal their sex to avoid detection by police by changing dress and other means.
Intersex — intermingling of sexual characteristics of either sex in one individual to a varying degree, including the physical form, reproductive organs and sex behavior.
Gonadal agenesis: In gonadal agenesis testes and ovary have never developed. Nuclear sex is negative.
Gonadal dysgenesis: In gonadal dysgenesis, the external sexual structures are present, but at puberty the testes/ovaries fail to develop.
Klinefelter’s syndrome: Anatomically malebut nuclear sex is female. Sex chromosome pattern is XXY (47 chromosomes).
Turner’s syndrome: Anatomically female, but the nuclear sex is male. Sex chromosome pattern XO (45 chromosomes).
True hermaphrodites: This is a condition of bisexuality. Here both ovary and testis (ovotestis) with external genitalia of both sexes exist in one individual.
Bilateral true hermaphroditism: There is a testis and an ovary (ovotestis) on each side.
Unilateral true hermaphroditism: There is a testis and an ovary (ovotestis) on one side and either a testis/an ovary on the other side.
Alternating true hermaphroditism: There is testis on one side and the ovary on the other side.
Pseudohermaphrodite:
Female pseudohermaphroditism has male external features, but internally has the female gonads.
Male pseudohermaphroditism has female external features, but internally has the male gonads.
Hormonal intersex: In a female pseudohermaphrodite, an excess production of androgenic hormone by adrenal cortical hyperplasia can modify the external genitalia of a genetic female.
Hypertrophy of the phallus, fusion of the labia majora and hirsutism may cause the parents to consider their child to be a male.
Psychological sex: Many men and women are psychologically dominated towards sexual inversion, a persistence of the childhood tendency.
Environment and upbringing: This decides the sex of rearing.
Increase in mass disasters often utilises race and racial characteristics in establishing the identity of victims.
As per Blueman Backs classification there are five human races on the basis of skin colour, and they are:
Caucasian (white)
Mongoloid (yellow)
Ethiopian (black)
American (red)
Malayan (brown).
Race determination usually depends on following:
Morphological characteristics/traits
Osteometric parameters: Osteometry in anthropological sciences comprise measurements of different bones in the body, assessing its proportionalities to each other and multivariate discriminate functional analysis.
Cephalic index (CI) — the ratio between breadth and length of the skull.
Vedic religion gave rise to what is now the oldest extant and World’s third-largest religion, Hinduism; the Abrahamic religions of Islam and Christianity, spread by missionary activity and conquest over many centuries, are the two other largest non-native religions.
Rest of the smaller groups of religions existing in India are: Sikhism, Buddhism, Jainism, Zoroastrianism and Judaism.
A typical Hindu male will wear dhoti, kurta as traditional dress.
Among the Hindus, in certain community namely Brahmins will have a total shaved scalp except a tuft of hairs grown long on the occipital protuberance region.
These individuals may paint a tilakum/vibhooti on the forehead and other parts of the body also such as front of the trunk, side of upper arms, forearms, front of neck etc, made up of sandalwood paste/vermilion/turmeric.
They may also wear a sacred thread which is a big loop of thread made up of six strands, worn on the chest across the left shoulder; a necklace of Rudraksham beads worn around the neck.
A typical Hindu female will wear a sari and choli, etc.
Married women will usually wear a beaded necklace made up of red corals and black beads and a thread (Mangolasutra/Tali) with application of vermillion (Kumkum) over the forehead on the hair partition/hairline.
They may also wear a nose stud made up of diamond/white stone on the left ala and silver toe rings on the second toe of both feet.
A typical Muslim male will wear pyjama and salwar.
Most of them will have a tapering beard.
It is customary/traditional for a male Muslim to submit himself for circumcision of the penis as early as 5-7 years.
There will be callosities over the forehead, and lateral malleolus of the left leg due to the particular position opted during the practicing of prayers—Namaz.
A typical Muslim female will wear a shalwar and kameez, etc. with a black gown (Burkha) covering completely, hiding the person from head to toes, except over eyes.
They will wear multiple nose and ear rings; will thus have their nose pierced over the ala as well as the nasal septum and on the margins of the helix and lobule of both ears.
Nationality and Language: Characteristics representing nationality of a person and language spoken may also help in establishing the identity of a person.
The type of dress worn, articles preserved in the pockets and wallets, passport, a tattoo mark/words inscribed, etc may reveal the nationality and language spoken.
In a living person talking to him/her can easily express the language identity.
Criminal identification by means of fingerprints is one of the most potent factors in apprehending fugitives who might otherwise escape arrest and continue their criminal activities indefinitely.
This type of identification also makes possible an accurate determination of the number of previous arrests and convictions, which results in the imposition of more equitable sentences by the judiciary.
Finger-print identification — the method of identification using the impressions made by the minute ridge formations or patterns found on the fingertips.
The friction skin of the palms and soles differs significantly from the skin covering the rest of the body as follows:
It is hairless and with no oil glands or any pigments.
This friction skin also has higher concentration of sweat glands, and these accrine sweat glands contribute mainly to the fingerprint residues.
Loop — usually begins on one side of the finger and ends on the same side. When this happens from the ulnar side it is called the ulnar loop and if on the radial side — radial loop.
Whorl: This could be having multiple circular/oval ridges, one around the other, or a single ridge, round in multiple rounds.
Arches:
Plain arch — when it is wave-like.
Tented arch — when the arch is sharp and spike-like.
Composite — It is a combination of more than one pattern, either a combination of arch, whorl and loop, or two different patterns: two whorls and arch or loop.
Accidental variety — no specific ridge pattern is available.
Central pocket loop: Here, surrounding the central circular/ oval ridge, there are other ridges which take a loop like course.
Type line: In loops and whorls, the ridges in the middle/ main part are surrounded by divergent ridges.
Delta: In loops and whorls, the point of the outermost ridges nearest to the damaged type line. Arches have no delta.
Core: In loops and whorls, the apparent central point of the ridge pattern.
Wash the finger properly with soap and water.
Ink the ball of the finger with printer’s ink.
Use an unglazed white paper.
Take finger-print in two different types:
Plain fingerprint by just pressing the inked ball of the finger on the paper.
Rolled fingerprint by pressing the inked finger ball, roll it from one side to the other side of the finger.
Epidermal ridges in the skin of palms and soles are developed as early as the 4th month of IUL.
Finger-print is a 100% accurate method in establishing identity. No fingerprints of 2 individuals, even in case of monozygus identical twins are similar.
Visible fingerprints: Fingers when smeared with blood, grease, etc. will leave their prints/impression on the weapon used for the crime/ furniture or such other articles that may be touched by criminal at the scene of crime unintentionally and can give clue for identifying the criminals.
Latent fingerprints (invisible fingerprints): Finger-print experts can render a faint and invisible/latent finger-print visible by special techniques using some developing agents, which are chemical powders and liquids.
Plastic fingerprints: These are prints of the finger left on soft materials such as wax, soap, dust, etc.
Fingerprints from dead body: Tip of the finger may get shriveled in a dead body and then may mask the picture.
Fingerprints are important because they can be transmitted easily from one place to another by telegraphic message easily.
FINDER-II — FINgerprint reaDER; can read the data about fingerprints such as ridges, bending, ridge bifurcation, image direction of fingerprints, etc.
In the FINDER-II system only 8 fingerprints are taken into consideration, excluding the little finger.
Poroscopy — study of fingerprints described by Locard providing absolute identity.
The papillary ridges of the skin of the finger balls and hands will have plenty of minute pores, which are the openings of sweat glands.
These pores are permanent and vary in shape, size, position and numbers over a given length of a ridge in each person, rendering them ideal factors for establishing identity.
When the finger-prints available are only a fragment and not complete.
The skin pattern of toes and heels from the sole of the feet are distinctive and permanent-can tell identity.
It is taken by using printer’s ink and a clean paper.
Spray the impression in the soil or sand with 80% of alcohol solution of Shellac. This hardens the soil or sand.
Next, smear the hardened surface with lubricant or dust with French chalk.
Then, pour an aqueous mixture of plaster of Paris and allow it to dry and on drying remove the cast and study the impression.
Footprint will be larger on walking than on standing.
Imprints left on soft and loose material like sand will always be smaller.
Look for any deformities like — flat foot, webfoot, supernumerary toes, loss of toes, etc.
The footprint of Newborn Infants: Usually taken in certain maternity hospitals for the simple reasons that foot-prints are very reliable means to identify newborn infants, if there is any mix-up of babies and mothers.
Body features also help one’s identity.
Color of iris of the eyes
Size and shape of ears and nose
Shape of the chin
Presence on the skin of:
A mole (nevus) which could be plain/hairy/big/small/tiny/ flat /raised and black/brown/red, etc.
A birthmark which could be an irregular colored patch on the skin.
Identikit — a powerful investigative tool that can create photorealistic facial composite sketches based on verbal description provided by a witness or victim about the criminal, which can help generate customized “wanted” posters.
Ear Prints: Shape, size, positioning, display, etc of the ears have been used to help in determination of human identity.
Broad, wing like soft/hard
Lobules of the ear may be wide and look freely hanging/ fixed to the face
Whole ear may be tending to come forward/backwards .
Ears may have hairs on the helix and tragus, seen only in male (linked to Y-chromosome).
Nose Prints: These are also chance prints, may be found at the crime scene on the mirror, corners of the walls, doors and so on. It may also be seen on the body of the victim/assistant.
The Roman nose: This type of nose is convex, like a hook. The word aquiline is derived from the Latin word ‘aquilinus’ which means ‘eagle like’.
The Greek nose: This type of nose is perfectly straight with no curves or hooked like shape.
The Nubian nose: This type of nose has wide nostrils. It is generally a little narrow at the top, thick and broad at the middle and wide at the end.
The Jewish or hawk nose: It is very convex, to the extent that it almost looks like a bow. It is very thin and sharp as well.
Snub nose: This type of nose is quite short and is neither sharp, nor hook-like nor wide. It is almost as short as a nose possibly can be.
The turn up nose: This type of nose is also called the celestial nose. It is so called because it runs continuously from the eyes towards the tip.
Palato Prints (Rugoscopy): Anterior part of the palate has rugae or grooves and ridges on either side of the midline which is considered to be individualistic and help establish identity.
Lip Prints (Cheiloscopy): It may be recovered on the wine bottles, glasses, on love letters/ notes, windows, doors, crockery items, cigarette buts etc.
Suzuki and Tsuchihastu coined the terminology figure linearum labiorum rubrorum for the grooves on the lip prints and classified them in to six types:
Type I — Clear-cut grooves running vertically over the lips
Type I1 — Partial length grooves of type of variety
Type II — Branched grooves
Type III — Intersected grooves
Type IV — Reticular
Type V — Other patterns
Electrocardiogram (ECG): It has been reported that the ECG pattern has unique, specific, individualistic characteristics which can help in establishing human identity.
Nail Prints: Ridges on the surface of the nails, their number, dimension of each ridge, their depressions and elevations, all in all are of help as unique factors in establishing human identity.
Hairs: When a material, alleged to be a hair is given for forensic examination, one may have to establish the following:
Confirm it as a hair
Confirm it as a human hair
Site of origin of hair
Injury to hair
Singed hair — peculiar hair showing changes in its morphology due to flame burns or fire arm injury.
Hair and stains on hair
Hair and identity
Hair and poisoning
Hair and miscellaneous information.
Characteristics | Human Hair | Animal Hair |
---|---|---|
Texture | Fine, thin | Coarse, thick |
Cuticular Scale Pattern | Small, flat, serrated | Large, polyhedral, wavy |
Medulla | Narrow | Wider |
Pigment | Cuticle | Medulla |
Precipitin Test | Positive | Negative |
Injury on the Hair | Type of Weapon/Injury |
---|---|
Cut end is clean, if seen fresh, but turns round in few days | Sharp Weapons |
Cut end is crushed out | Blunt Weapons |
Bulb is distorted, irregular and swollen, if seen fresh | Forcibly Plucked Hair |
Bulb atrophic small and shrunken off with smooth surface | Naturally shed hair |
Type of Stain | Medical Information Derived |
---|---|
Mud stain | Struggle |
Seminal stain | Rape/Sexual Offenses |
Blood stains | Trauma/Injury |
Salivary stains | Asphyxial death |
Carbon particles in stains | Burns/Firearm Injury |
Presence of dyes | Concealing the natural color or age identity. |
Stature is defined as the height of a person.
Stature and Diurnal variation of Stature
Stature is proved to be varying at different times of the day, ranging from 1.5 to 5 cm. Stature of person is said to be minimum in the afternoon and in the evening, while maximum in the morning, after sleep.
Factors Affecting Stature Variation
Death can bring about body lengthening by about 1.25 cm for a male and 2 cm for a female on an average.
Determination of Stature
The length between outstretched fingertips of 2 middle finger is equal to the height (stature)
Length of one arm × 2 + 30 cm for 2 clavicles + 4 cm for the sternum is equal to the height (stature)
Vertex to symphysis pubic length = 1⁄2 of the height (stature)
Sternal notch to symphysis pubic length × 3.3 is equal to height (stature)
Length of entire skeleton +2.5–4 cm (For the soft parts thickness) is equal to the height (stature).
Stature from Skeletal Remains
Karl Pearson’s formula
Trotter and Glaister’s formula
Factors Affecting Multiplication Factor (MF)
Sex: Varies in male and female
Age: Varies in adults and children
Bones: Varies from one long bone to another long bone
Type of bone: Varies for wet and dry bones
Race: Varies from race to race.
Congenital — e.g. cleft lip, hare lip, cleft palate, overriding teeth, improper teeth, protruding teeth, moles, birthmarks, super numerary finger/toes (polydactylia), flat feet, webbed feet, etc.
Moles — small dark spot on the skin can appear at birth or later, anywhere on the body, and can be of a variety of shapes and coloration.
Naevi — group of lesions where moles are part of.
Birthmark — represents accumulation of skin pigment locally, with overgrowth of vessels, or other confined abnormality of the skin.
Moles and birthmarks are of great importance in establishing identity of a person. For identification purpose, they are described in relation to a nearby anatomical landmark.
Removal of the mole: Techniques of removing the moles include laser treatment, electrocautery technique and surgery.
Mole removal surgery — a very simple method as it allows the surgeon to be sure to remove it as an outpatient procedure, where an anesthetic and a freezing solution is applied to the mole, and then shaved it away with a scalpel.
Laser treatment and electrocautery technique — are effective only on very flat moles which are on the surface of the skin are both effective only with superficial moles in the surface layers of the skin and not in the deeper parts of skin.
Birthmarks are usually painless and harmless, but some may cause complications, such as pressure on other organs, they may be linked with congenital diseases, or, rarely, may transform into a malignancy, which means it is better a birthmark be examined by a doctor.
Tattoo marks are fairly good identification marks, both for living and dead subjects. Imprinting pigments of different colors in the dermis by multiple puncture methods produces tattoo marks.
Carbon dust, Indian ink, indigo, Chinese black, Prussian blue, cinnabar, cobalt, vermilion, etc. Some of the chemicals contents of different color pigments used for tattooing are:
Red pigment – Mercury
Green pigment – Chromium
Yellow pigment – Cadmium
Blue pigment – Cobalt
Tattoo marks mostly represent personal details, details of the favorites, beloved, lover, friend, relatives, pets, place of living, religious beliefs, sexual fantasies, etc.
Alteration of a tattoo mark is possible. It can be done by over tattooing with titanium oxide or with white pigments.
Tattoo marks are fairly permanent, and stay life long if the pigments are placed in dermis and on the covered parts of the body.
Tattoo marks may be removed/eliminated. Certain methods by which the tattoos can be erased are enumerated below:
Surgical skin grafting (plastic surgery)
Local use of corrosive
Electrolysis which releases and dissolves the pigments to be washed out;
Applying carbon dioxide snow
Inflicting injury over the area or by dermabrasion
Application of caustic substances
Exposure to laser beams
Cryosurgery, etc.
Designs drawn can help establish the identification of race, nationality, occupation, religion, language, name of the person or his/her beloved ones, relatives, friends, etc.
The designs could be of an idol, obscene figure, a flower, etc. often represent the mental make up, desire, inclination, etc. of an individual
Identification by tattoos is possible even in a highly decomposed cadaver, as long as the dermis is intact.
Attempts for concealment of tattoo marks artificially is strongly suggestive of concealment of identity with a positive criminal background.
A tattoo at times may cause infection (even AIDS), sepsis, ulcer, keloid formation, etc.
Drug addicts may conceal the site of injection by a tattoo design.
Those who practice abnormal sex like homosexuals may tattoo a specific design to recognize each other.
Tattooing and firearm wounds: The unburned gunpowder may also cause tattooing or semi burnt gunpowder particles from a firearm discharge, around the wound of entry, and can give clues regarding the firearm injury and also the range of firing— involuntary tattoo marks.
Medical and practical applications of tattooing: Tattoos have a number of legitimate medical applications.
Nevi flemmi have been tattooed for camouflaging it, vitiligo patients can be tattooed to almost normal skin color.
Facial tattooing is the latest trend in cosmetic surgery.
Correctional tattooing is promoted to get permanent eyelashes and eyebrows etc tattooed in a required style. It has also been used to create nipple and areola after breast surgery.
Color defects in the lips after facial surgery can also be observed by tattooing.
Scar is a product of healing of a wound by fibrosis and cicatrization.
It is permanent and may change in its size during the growing ages, but its shape remains unchanged all throughout the life, if there is no keloid formation or any other interference, renders it an important means of establishing human identity.
Scars are permanent and they relatively do not change in their shape, position in relation to anatomical landmarks of the body; they can constitute an ideal factor for establishing the identity of a person.
A scar with keloid formation may not be of any help as an ideal entity for identification purposes.
Scar can also give clues regarding type of injury or blunt force trauma and thereby the type of weapon used, time since injury, causative weapon, etc.
The umbilicus: It is an iatrogenic/doctor given, permanent that has no medicolegal importance.
Strial albicantes are multiple parallel whitish lines on the lower abdomen of a woman who has undergone pregnancy and delivery.
Hypertrophic scars and keloids: Hypertrophic scars usually settle or begin to regress in 6 months.
Keloids may extend beyond the wound itself and continue to increase in size by 6 months.
Extensor surfaces, strong and burned skin are the commonest site of appearance.
Negroes and young people are more often affected.
A scar over the antecubital region or dorsum of hand may be a clue about drug addiction.
Striae gravidarum are scars of past pregnancy or tumor in the abdomen.
Scar on the victim may be claimed as that of an infected wound by the accused.
Scar may be changed surgically into different shape or completely erased by plastic surgery to avoid implication with a criminal offense.
An apparently invisible scar may be made visible by ultraviolet rays, by application of heat or rubbing.
A scar may be developed after the removal or erasure of a tattoo or destroy finger-prints to avoid identification.
Scars being less vascular and fibrous in nature can resist putrefaction and thus help in partial identification of the deceased.
Scar on the knees should not be considered for identification purpose as they are common in most of the people due to frequent injuring due to falls during the childhood
Anthropometry — science of measuring body parts.
It is assumed that after the age of 21 years the skeleton stops growing and hence the measurements of various parts of the body remain constant.
It is also assumed that no two people will have bones of identical dimensions.
Only applicable in adults
Errors in taking measurements by instruments.
Needs measurements of various parts of the body
This has been replaced by dactylography technique.
Large number of occupational stigmas can be of help broadly in determining the job of the deceased, and thereby be of great help to investigating agencies in narrowing down their investigation for identifying the unknown individual, have been described in literature.
Presence of grease, paint, dust, etc. on the body and garments worn can give clues regarding the occupation of a person and thereby establish partial identity of a person alive or dead.
Presence of grease — suggestive of mechanic
Presence of linear callosities on the fingers of the left hand — violinist, guitarist, etc.
Postural Trauma Callosities in Namazis over the bony areas of the body which are pressed against the ground during ‘namaz’ (prayer) have been described.
The degree of thickening or callositing may not be well appreciated in Namazis who use soft carpet flooring.
Presence of callosities on the toes.
If a photograph of a missing person (front profile) is available and the skull with mandible is both recovered, this technique may be used in ruling out that the skull belongs to the person in the photograph.
Enlarge the photograph to ‘life size’, the enlargement factor being based upon the measurements of the fabric of the deceased, or other measurable items seen in the photograph, or the focal length of camera lenses used, or the dimensions of the anterior teeth, etc.
The skull is adjusted in such a way that the inclination and orientation are same as that of the head in the photograph.
A life size picture is taken and superimposed on the transparency of life size antemortem photograph, making allowances for soft tissue and hair thickness.
The anatomical landmarks are then compared for a positive match.
Examine the following characteristics in the superimposed photograph:
Outlines of skull and mandible fit into the outlines of head and face in portrait.
Vault of the skull to hair line.
Eyes to orbits.
Nasion with origin of nose.
Nasal aperture with nose.
Nasal spine in centre which is little above the nose.
Prosthion in the central line.
Upper border of the upper jaw i.e. below the tip of the nose.
Teeth in relation to lips.
Zygoma over the highlights below the eyes.
Tip of the mandible (Gnathion) with chin.
Position and shape of upper jaw with general contour of cheeks.
Slight variations in magnification of antemortem photograph or slight change in angulations of the skull from that of photograph can lead to major discrepancies resulting in a mismatch.
The method is laborious and time consuming.
Step 1
The antemortem photograph, preferably with a smiling face exposing the teeth is now mounted close by.
A color video camera firmly mounted on a tripod is aligned at right angles to the antemortem photograph.
The center of the lens of this camera should be at the same level as the horizontal center of the photograph.
Step 2
The dry skull without any soft tissue/ any foreign matter on it is mounted on an adjustable support allowing movement in all the three planes.
Keep a contrasting background behind the skull.
Another color video camera is firmly mounted on a tripod in a same way as the previous.
Step 3
The video signals from both cameras are fed into a vision mixer so that a variety of functions like horizontal and vertical wiping, superimposition, and negative simulation can be performed.
The skull is oriented on the adjustable mount as closely as possible to the angulations of the head in photograph.
The video pictures from both cameras are relayed into the video mixer.
By adjusting the mixer, the video picture of photograph can be enlarged.
The video mixer will offer all flexibility here in making the adjustments and provides immediate results without having to process photographs or make tracings.
After correct enlargement and orientations, superimposition is done, and features are compared with respect to the landmarks.
Video mixer can help fading in and out of either pictures, or sweeping over each other in vertical or the horizontal plane.
The procedure allows even part of the skull or the photograph to be superimposed in either the vertical or horizontal plane on the video screen so that an accurate match is obtained.
The technique can be video taped. Taped material can be used for court purposes also.
The actual experiences of the perpetrator or witness are encoded in a very specific manner in his/her brain.
This would be revealed during the course of the Electroencephalogram (EEG) and the carefully formulated probes used to stimulate his brain waves.
Probes are the key words or phrases compiled with the help of the investigating officers, act as a trigger for the person under scrutiny.
Investigators may ride brain waves to nail the culprits.
In the polygraph (lie detector), the machine takes note of the subject’s suppression or anxiety in divulging information. But with the brain finger-printing we can go beyond that.
Ethical dilemma — the scientific research reports needs thinking about its ethics of any such a method.
When two objects collide or come in contact with each other, there is always transfer of materials from one object to the other.
A criminal who commits a crime often leaves some traces at the scene of crime or takes something away from the scene or from the victim.
The investigating officer has to play a vital role in this work, when the trace evidence materials are to be collected from scene of crime.
The forensic expert who has to play vital role in collecting trace evidence materials from a living individual or a dead body at mortuary.
Living person: Seminal stains in an alleged rape victim, blood stains of the victim on the body of the accused in an alleged assault, brought for medical examination.
Dead body: Salivary dribbling marks on the front of the dead body in a case of hanging which is suggestive of antemortem hanging.
Blood: It is the most important body fluid, which easily escapes during any assault, injury, murder, vehicular accident and sexual crimes.
Bloodstains: These are often present on the clothes, weapons, floor, furniture, wheels or part of a vehicle, at the scene of crime, on the victim or the assailant.
Whether the stain is blood or not: This can be decided by routine/screening and confirmatory tests.
Routine test:
Benzidine test: Here a negative test is of more importance as it rules out blood, but a positive test is not of significance as vegetable stain, pus, saliva, milk, rust, etc. stains can also give positive reaction with this test needing confirmatory test to prove blood.
Confirmatory tests include several testing:
Microchemical tests — based on the property of hem (iron) part of hemoglobin to form characteristic colored crystals with certain reagents, and these crystals can be seen only microscopically.
Microscopic examination — possible only with a fresh stain and one can clearly identify the RBCs and WBCs, which helps in confirming the stain as blood.
Spectroscopic examination — needs only a very small quantity of stain. This test depends on property of the translucent colored fluid to absorb certain rays from the solar spectrum.
Whether human or animal blood: This includes serological test namely precipitin test — this is a sensitive test based on an antigen-antibody reaction.
Blood group of the stain — According to the antigens present on the surface of red cell membrane, the blood can be classified into four major group: Group A, Group B, Group AB, and Group O.
Universal Donor — group O blood.
Universal recipient — group AB blood.
Sex of the bloodstain: determined by the examination of leukocytes. The neutrophil contains a drumstick nucleus in females only. This drumstick nucleus is known as Davidson’s body.
Age of the stain: Color and nature of the stain can help in establishing age of the stain as follows:
Blood when fresh is bright red in color.
In 24 hours—it is reddish brown.
More than 24 hours—it is dark brown and for a longer duration it becomes black.
If the stain is fresh—it is moist and sticky.
If the stain is old—it is dry and scaly.
Whether arterial or venues blood
If blood is of arterial origin—it is bright red.
If blood has venous origin—it is dark red.
Shape Of The Bloodstain And Opinions Derived
Circular marks — fall from short height.
Circular with irregular margins — fall from moderate height.
Needle-like projections at the margins — fall from a distant range of angles.
Arterial bleeding is in spurts and bright red in color
Venous bleeding is oozing and dark red in color.
Nasal bleeding — Blood mixed with nasal mucous and hair.
Stomach or gastric bleeding — Chocolate color due to the presence of acid, haematin and is acidic in reaction.
Menstrual bleeding — Dark colored fluid blood with foul smell and with endometrial debris, acidic reaction, vaginal epithelial cells and bacteria are present.
Abortion bleeding —Dark clotted blood. Endometrial and placental debris with fetal remnants sometimes present.
Antemortem bloodstains get broken into scales due to the presence of fibrin, whereas the postmortem bloodstains become powder.
The stains, which resemble bloodstains, are paint, iron rust, fruit and vegetable stains and synthetic dyes.
Semen and seminal stains:
The male at the climax of sexual intercourse ejaculates semen. About 2 to 5 ml is voided normally each time.
Semen — consists of sperms and seminal fluid, which is rich in sugars, proteins and enzymes.
In vasectomized and sterile persons, semen will not contain sperms.
Appearance: Semen and seminal stains has the following characteristics:
Freshly voided semen will be vicious, dirty white in color and will have a musty odor.
In white clothes, it produces a light yellow stain with a starchy feel on drying.
Uncolored clothes stains are visible only in ultraviolet light.
Saliva: It is the secretion from the salivary glands situated intra- and extraorally. The secretion flows through ducts from the glands opening into the mouth.
Composition of saliva:
Saliva consists of water, salts and various enzymes.
Amylase is the important enzyme present in saliva
Urine and urinary stains can be detected by chemical tests.
Grouping is also possible because urine contains group specific substances.
Feces and fecal stains can be identified by microscopic examination for the presence of undigested matter.
Feces contain stercobilin, which can be detected by chemical tests.
Grouping can be done using the absorption elution method.