DNA ANALYSIS.pptx

MODERATOR- DR.H.K.KHARTADE SIR
PRESENTER- DR.PRATEESH SHUKLA
METHODS OF DNA SAMPLING AND
ANALYSIS

AIMS AND OBJECTIVES
 To know basic structure of DNA.
 To know about DNA sampling.
 To know about various DNA extraction techniques.
 To know various methods of DNA profiling.
 Application of DNA profiling.
 Limitations of DNA profiling.
 Case studies.

Cont…
 Human DNA is double helical structure with two antiparallel
complementary chains.
 It was given by Watson and Crick.

Facts about human genome
• Human body consists of 60 trillion cells.
• Each nucleated cell contains DNA at two levels (except
RBC)
- Nuclear DNA in form of chromosomes. (nDNA)
- Mitochondrial DNA. (mtDNA)
• 23 pairs of chromosomes in human diploid cell and half the
number in haploid cells.
• Length of chromosome just before mitosis begins is
5micron.

Cont…
 Total DNA in a human haploid cell 3 x 10`9 base pairs (bp)
in 23 chromosomes.
 Each chromosome contains between 50 x 10`6 to 250 x
10`6 bp.
 When uncoiled these molecule range from 1.7cm to 8.5cm
 Total length of human haploid cell DNA when stretched
end-to-end is 1 metre.

Cont…
 About 99.5% of the DNA code is same for all humans and
only 0.5% varies which forms the basis of DNA profiling
and lies in non- coding region.
 Coding DNA – 3% (9 x 10`7 bp)
 Non Coding DNA (junk DNA) – 97%
- It consists of large arrays of tandem repeats of
nitrogenous bases.
- This repetitive DNA constitutes of 50% of human genome.
- Number of repeats is different in different persons k/a
Tandem Repeat Polymorphism (TRPs).

Cont…
 Genes are made up of DNA.
 Total number of genes in humans is 32,000 bp.
 Maximum number of genes are on chromosome 1
(4,220).
 Minimum number of genes are on chromosome 11
(379).
 X chromosome contains 1,846 genes.
 Y chromosome contains 454 genes.
 Average length of one gene is 3000 bp.

Cont…
 Chromatin is combination of DNA, histone and other
proteins that make up chromosomes.
 Its function is to package large lengths of DNA into smaller
volume to fit inside the cell.
 Has two forms heterochromatin (condensed form) and
euchromatin ( extended form).
 Heterochromatin stains intensely while euchromatin lightly.
 Heterochromatin contains mainly junk DNA while
euchromatin contains mainly coding DNA.
 Telomere and centromere are heterochromatic.

Cont…
 ‘TCAT’ is a repeating unit while the complete repeat is an
array or an allele.
 Total number of base pairs in an array is known as array
length or array size,
 Different persons have different array length or different
alleles.
 The location at which each of the repeating array sits is
known as a locus.
 Satellite DNA – Tandem repeats of non-coding DNA tends
to produce DNA with different density than rest of DNA.

Cont…
 When DNA is separated using buoyant density gradient
centrifugation, DNA fragments with significantly different
base composition are separated.
 They are seen as separate bands when analyzed by UV
absorption spectra.
 Main band represents the bulk DNA and additional bands
around it represent satellite DNA.
 Satellite DNA is same as junk DNA.

Cont…
 Components of satellite DNA-
1. Satellites – repetitive units with length of 100 bp to
several thousand bp.
- Found in heterochromatic region, near telomeres and
centromeres.
- Also present abundantly in Y chromosome.
2. Minisatellites or Variable Number Tandem Repeats
(VNTRs) - length of 7 – 100 bp, but usually 15 bp. Array
size is 500 bp to 30,000 bp.
- Found in euchromatic region of genome.
- Two types – a) Telomeric –size - 6 bp, mainly “TTAGGG”
in
humans.
b) Hypervariable - size – 7 to 100 bp,
usually 15 bp.

Cont…
3. Microsatellites ( STR or SSR) - length of 1 – 6 bp.
- Found throughout the genome.
- On an average occur every 60 kbp.
- Human genome contains an estimated 105 microsatellite
loci, of which about 104 STR sequences have been
published.
- Repeat units are dimeric to hexameric depending upon
the number of nucleotides in a repeat unit.
- Tetrameric units comprising about 10% of total STRs,
are the most commonly used STR loci for forensic
DNA profiling, followed by pentameric.

Cont…
- Both tetrameric and pentameric STRs give high degree of
error free data while being robust enough to survive
degradation in non ideal conditions.

DNA Polymorphism
 Difference between individuals at DNA level.
 Two types –
1. Sequence polymorphism - A DNA chunk at a given
locus differs in nucleotide sequence.
- Eg. Genes for normal haemoglobin, Haemoglobin H,
Haemoglobin S and Haemoclobin C etc have difference
sequence.
- A single nucleotide polymorphism (SNPs) is a type of
when just a single nucleotide differs between individuals.

Cont…
 Almost all common SNPs have only two alleles, binary in
nature.
2. Length polymorphism - a DNA chunk at a given locus
differs in the number of tandem repeats.
• Since both types of polymorphisms are present in non-
coding regions, it does not have observable phenotypic
effects.

Genetic (DNA) markers
 A genetic or DNA marker is a gene or DNA sequence with
a known location on a chromosome that can be used to
identify an individual.
 SNPs, Satellites, Minisatellites and microsatellites are
examples of genetic markers.
 Nomenclature of genetic marker –
1. If a marker is a part of a gene or falls within a gene, the
gene name is used in designation.
- Eg. a) TH01- The STR marker TH01 is from the human
Tyrosine Hydroxylase gene located on chromosome 11.
“01” portion of name indicates that the repeat region is
located within intron 1 of this gene.

- HUM is included at beginning of a locus name to indicate
human genome.
2. If a marker falls outside of gene, it is designated by its
chromosomal number and order of discovery.
- Eg. D5S818 – D stands for DNA , 5 means chromosome 5,
S means single copy sequence, means only occurs once
in human genome and 818 indicates that it is 818th DNA
marker and categorized in this chromosome.
- Eg. D17Z1 – Z indicates multicopy sequence.

DNAAnalysis
 Biological sample for DNA profiling
 Authentication and forwarding
 DNA Extraction
 Methods of DNA profiling
 Application of DNA profiling
 Limitations
 Case Studies

Biological samples for DNA
profiling :
 Using sterile uncontaminated clothes.
 Usual samples to be collected are:
 ❏ Blood - Bloodstains on carpets, cloth, floor
tiles, food, furniture, metal, newspaper, plastic,
vehicle, wallpaper, wood etc.
 ❏ Fetus – chorionic villus samples, muscle
biopsy.
 ❏ Hair – from head, moustache, beard, axilla,
public regions.

Cont…
 ❏ Nasal mucus
 ❏ Saliva - Cigarette butts, envelops, mouth
swabs etc
 ❏ Semen – suspected stains on cloth, floor tiles,
fur, furniture,
 matted hair (generally pubic), paper, vaginal
aspirate and
 swabs from anus, mouth, penis and vagina.
 ❏ Tissue - bone marrow, fingernail scrapings,
muscle, spleen.

Cont…
 A. Collection :
 If DNA evidence is not properly documented,
collected, packaged, preserved and forwarded, it
will not meet legal and scientific requirements for
admissibility in a court of law.
 For forensic purposes, samples are usually
collected from
 ➔ Living persons
 ➔ At the scene of crime
 ➔ At autopsy.
 (along with control samples) without any delay.

Cont…
 Autopsy tissue samples :
 (1) Bone marrow -
 ❏ Not to be preferred in a fresh autopsy, where
muscle is
 available.
 In skeletal remains, may be tried
 ❏ Femur and humerus are preferable as they
yield more bone marrow.
 ❏ Pack in clean paper or cloth.
 ❏ No preservative is necessary.

Cont…
 (2) Brain – Not preferred.
 (3) Kidney – Not preferred.
 (4) Liver - Not preferred, because of enzyme
degradation of DNA.
 (5) Lymph nodes - Good source of DNA.
Preserve in Dimethyl sulfoxide [DMSO].
 (6) Spleen – Good source.

Cont…
 (7) Putrefied bodies - Take teeth, one long bone.
Hair generally not useful
 (8) Skeletal muscle (deep) - best for DNA
 (9) Skin - 2-5 g.
 Second best, after muscle. Should be stripped of
fat, as there are difficulties in dissolving fat in the
lab.

Cont…
 BLOOD :
 (1) Highest DNA content.
 Liquid blood may not be available in all situations
(eg from scene of crime). Therefore dried blood
may have to be sent.
 (2) Liquid blood :
 ❏ May be taken from living or from relatively
fresh dead bodies
 ❏ Preservative - EDTA is preferred
 ❏ At least 5 ml - Purple stoppered Vacutainer
(EDTA tube).

Cont…
 (3) From dead body :
 ❏ Liquid heart blood can be taken in a gauze
piece, dried and sent.
 (4) Clotted blood :
 ❏ Not a good source of DNA, because of settling
out of WBCs.

Cont…
 DNA based Forensic Odontology :
 Oral cavity provides several sources of DNA
(Mucosal swabs, saliva, teeth).
 (a) Saliva
 Forensic value - desquamated epithelial cells →
DNA can be extracted.
 Collection from the living : (i) Whole saliva is
collected normally either as resting or stimulated
(chewing on paraffin or using a small citric acid
crystal).

Cont…
 (3) Collection from dead :
 (i) For identification of assailant - May be
necessary if dead body shows bite marks.
 (ii) For identification of victim – Rarely needed,
eg if victim had a blood transfusion during last 3
months, it is not advisable to take blood or organs
perfused with blood.
 (iii) Procedure - Suspect area swabbed with
distilled water; swab dried (in moist condition,
there is danger of bacterial and fungal growth)
and sent to lab. Take swab from mouth in case of
victim identification.

Cont…
 (b) Teeth :
 (1) Useful because teeth resist mass disaster and
genetic material is protected by the calcified
tissues.
 (2) If Skull containing teeth is available –
 (i) Detach molar teeth from upper and lower jaws
and send in paper bags
 (ii) If molar teeth not available, send other teeth
 (3) Cleaned and stored in normal saline.

Cont…
 (4) Sources of DNA (i) dentin (ii) pulp (iii)
cementum (iv) periodontal fibers (v) attached
bone fragments.
 (5) Dentin - consists of cellular extensions
(Tome’s fibers) rich in mitochondria. Good source
of mtDNA.
 (6) Pulp tissue - most commonly
 It is abundant
 Has least chance of contamination by nonhuman
DNA.

Cont…
 Fingernail scrapings
 (1) Useful in sexual assault cases
 (2) Procedure -
 Place palm of victim on a clean paper
 scrape inner portion of fingernail with a toothpick
 fold paper and send.

Cont…
 Semen and vaginal swabs
 Useful in rape cases.
 Air dried and sent in paper envelops.
 They are porous and do not allow moisture to
develop.
 Polythene envelops are not to be used, as they
are not porous → Moisture develop → fungal
growth → degradation of DNA.

Cont…
 Hair –
 Pulled from dead body, so that nucleated root or
follicle cells are available in sufficient numbers.
 Generally 10 hair are sufficient.
 Naturally shed hair, as from combs and
hairbrushes may have little or no root material.
 Send hair only when nothing else is available. Not
to be used as first choice

Cont…
B. Preservation :
 (1) Freezing :
 (i) Best. Place tissue in aluminum foil; put foil in
plastic bag; freeze
 (ii) Up to 5 days : may be stored in ice
 (iii) Up to 5 weeks : -70°C
 (2) Dried objects – like bone, dried blood stains
etc need no
 preservatives
 (3) Formalin – Never preserve in formalin; it
destroys DNA.

Authentication and Forwarding
 (1) For paternity disputes : blood samples taken
in the presence of a judicial officer.
 If samples are taken from autopsy, such
procedure is not required.
 (2) Sealing – sealed, and a specimen of seal
should be sent separately on a plain paper.
 (3) A signed identification label - should be placed
on all samples.

Cont…
 (4) Forwarding note - should accompany
samples, stating clearly what the sample is, from
whom it has been taken, and what exactly is
required and why.
 (5) If person has had blood transfusion within last
3 months – May lead to errors. In such cases,
other samples eg saliva may be sent.

DNA Extraction
 Before DNA profiling can be done it must be extracted from
cellular material.
 Extraction can be of two types :
Normal Extraction
Employed when there is no inter mixing of samples.
 Step 1 : Cell disruption
- Alkali treatment
- Boiling
- Enzymatic Digestion e.g. Proteinase K
- Grinding – materials like bone & teeth are frozen in liquid
nitrogen and grinded to fine powder.
- Sonication – Application of ultra sound to disrupt cell
membrane

 Step 2 : Removing of nuclear/ mitochondrial
membrane
- Adding detergents – E.G. Sarkosyl and Sodium
Dodecyl sulphate (SDS) – they dissolve membrane
lipids, denature protein and dissociate proteins from
DNA.
 Step 3 : Separation of DNA from proteins and
cytoplasmic contaminants
- Addition of high salt conc. mixtures – dissociate nuclear
proteins such as stones from DNA.
- Using Phenol:Choloform:Iso-Amyl Alcohol Mixture
(25:24:1)
• Phenol-Chloroform makes the organic phase in which
lipids are dissolved
• Iso-Amyl Alcohol reduces foaming
• DNA dissolves in aqueous phase
• Proteins are concentrated at the junction of two

- Addition of high salt conc. mixtures – dissociate nuclear
proteins such as stones from DNA.
- Using solid silica surfaces
• DNA is reversibly adsorbed to silica in the presence of
high conc. of chaotropic salts like Guanidinium Salts
(e.g. Guanidinium Thiocynate (GuSCN) and
Guanidinium Hydrochloride (GuHCl)
• Silica is washed with ethanol
• DNA is then separated by rehydration with aqueous
low salt solution

Various methods of Gene extraction

 Step 4 : Preservation of DNA from degradation
- Adding a buffer system like Tris-HCL – maintains pH to
prevent activity of degrading enzymes.
- Reducing Agents like Mercapto-ethanol or
DiThioThreitol (DTT) to inhibit oxidation process
- Gelating agents e.g. EDTA or Chelex – capture divalent
metal ions, which are co-factors of endogeneous
DNAses that catalyzes the hydrolysis of DNA.
 Step 5 : Precipitating DNA with an alcohol
- Usually ice cold ethanol or isopropanol is used.
- DNA is obtained in form of pellet upon centrifugation.

Differential Extraction
- Employed when there is inter mixing of samples like in
case of sexual assaults when vaginal epithelial cells and
sperm cells are mixed
- Sperm plasma membrane contains proteins cross linked
by Disulphide bonds, so it is more stiff.
 Step 1 : SDS and proteinase K are added to mixture,
vaginal epithelial cells are lysed but no effect on sperms.
 Step 2 : DTT which causes lyses of sperms.

FTA Paper (Flinders Technology
Associates)
 It is a specially treated paper to extract, bind and protect
DNA from degradation.
 It was developed in late 1980’s by Lee Burgoyne at
Flinders University in Australia.
 Composition : Absorbent cellulose based papers which
contains 4 chemical substances.
 DNA on FTA papers is stable at room temperatures over a
period of several years.

Methods of DNA Profiling
Forensic samples can be of 2 types :
1. Fresh undegraded samples (as in paternity testing)
2. Degraded samples (as in cold dried blood and seminal
stains)
 DNA breaks up into smaller fragments.
 More severe the degradation, fragments get smaller.
 Average size may become smaller than any length at
particular locus.
 Allele sizes for – mini satellites (VNTRs) – 500-30000 bp
micro satellites (STRs) – 10-500 bp
 In a degraded fragment the size <500bp
 Thus different techniques are used for fresh samples &
degraded samples.
 In Fresh samples - mini satellites are detected by RFLP
 In degraded samples - micro satellites are detected by
STR analysis usingPCR.

Restriction Fragment Length
Polymorphism (RFLP)
 First technique used for forensic DNA analysis by Alec
Jeffreys.
 Refers to multiple variation within different individuals of
DNA fragments cleaved from their genome by
restriction endonucleases.
 Due to DNA polymorphism, length of DNA fragments
obtained from different individuals is different.
 DNA fragments are typically 500-30,000 bp in size.
 Usually for analysis band size is 4000-20000 bp, as below
4000 bp band size reliable comparisons could not be
made.
 VNTR loci are hypervariable, each showing 100 or
more alleles, so 5-8 loci are sufficient to differentiate

Cont…
Steps involved –
1. Extraction of DNA
2. Digestion of DNA into fragments using specific
restriction endonuclease.
3. Electrophoretic separation of fragments based on size
by Agaros Gel (1%) electrophoresis – applicable for
fragments from 500-25000 bp.
4. Denaturing the double stranded DNA fragments in a
pH environment. - Agrose gel is soaked in a weak
alkaline solution to denature DNA strands.

Cont…
5. Transferring single strands of DNA out of
the gel onto a membrane support (either
nitro cellulose or nylon). This technique is
known as Southern blot developed by
English Microbiologist Edwin Southern in
1975
Northern Blot – to detect RNA,
Western Blot – to detect proteins,
Eastern Blot – to detect protein post-
translation modification

6. Hybridizing the immobilized DNA fragments with
specifically labelled DNA probes.
 If 2 complementary single strands of DNA are mixed
together they will hybridize together.
 If a single DNA strand is synthesized using radioactive
phosphorous then a radioactive strand of DNA is
obtained which serves as a probe
 Probes – 2 types – Multi locus & Single locus
Multi locus –
 can be attached to multiple VNTR loci
simultaneously
 depends on the fact that some VNTRs share a short
CG-rich core
sequence of 10-15 bp
 MLP is a mirror image of this core sequence
Restriction Fragment Length Polymorphism
(RFLP)

 CDFD - Centre for DNA Finger Printing &
Diagnostics,
Nacharam, Hydrabad uses an MLP derived from
female Banded
Krait (BKm)
 It can detect >35 VNTR loci
 Advantage -
o Excellent discriminating power used with great
success in parentage testing
 Disadvantage -
o Interpretation of a mixed DNA sample from >1
individual is nearly impossible
o does not perform well on degraded & limited
quantities of DNA
Cont…

Single Locus–
 Recognizes only specific region at a single locus
 Produce only one band or homozygous individuals
 Discriminating power of SLPs can be increased by
using different probes sequentially with a single locus
at a time
7. Detection of hybrid products by auto radiography or
chemiluminisence
 Nylone membrane is pressed against X-ray plate for
24 hrs
 Bands appear on the X-ray plates as dark lines
depending where the probes are attached
 This is known as an autoradiograph (autorad)
 These bands are specific for each individual & are
Cont…

Disadvantage of RFLP –
 Degraded samples can not be analyzed as VNTR
sequences are broken
 Large amount of DNA is needed, typically 50-100 ng
 Work with radioactive substances is hazardous
 Procedure takes minimum 1 week.
Restriction Fragment Length Polymorphism
(RFLP)

Short Tandem Repeat (STR) analysis
using PCR
 Refers to preparing a profile of multiple variations
within different individuals of small DNA
fragments of less than 500 bp, belonging to
microsatellite region of DNA.
 Steps –
 1) Determining the amount of DNA in sample (
DNA quantitation) –
 Since STR profiling is PCR based a narrow
concentration range is required for successful
amplification.
 If starting material is too much – artefacts may
interfere test results.
 If starting material is too low – result in partial or
no DNA profile.

Cont…
 2) PCR amplification- by Kary Mullis in 1989.
 Performed when DNA amoutnt is too little or too
degraded.
 Analysis can be performed with just 200 pg of
DNA.
 Dependent on thermo stable enzyme Taq
polymerase.
 It is obtained from thermophilic bacteria Thermus
aquaticus.
 Its essential feature is that it can multiply DNA
fragments even in high temperatures.

Cont…
Steps of PCR amplification-
I. Denaturation-
 Accomplished by subjecting DNA to 94 degree
Celcius.
 Double stranded DNA is converted to single
stranded DNA.
 Success of PCR depends on thermal stability of
DNA polymerase enzymes.
 Taq polymerase is the most commonly used
DNA polymerase.

Cont…
II. Annealing –
 It involves annealing of DNA primers.
 Temperature is brought down to 60 degree celcius.
 Primers are like probes used in RFLP are short
synthetic pieces of DNA, usually 16 – 25
nucleotides.
 They match defined locations by complementary
base pairing.
 Two different primers define the end point of a
particular segment that is to be amplified, one at
each end.

Cont…
 Each primer is labeled at its 5’ end with fluoroscent
dye to detect it by LASER later.
III) Extension-
 temperature is brought to 72 degree celcius.
 Raw material in form of nucleotides is added.
 Primer carries complemantary base to original
strand one by one.
 This way a complemantary strand is created to the
original strand and the area of interest is duplicated
at the end of one cycle
 Repeated 20- 30 time, millions of copies are
created.

Cont…
 Amplified product is called amplicon and process
is sometimes known as molecular xeroxing.
 DNA amplification by other methods-
i) Ligase chain reaction (LCR)
ii) Q beta replicase
iii) Self sustained sequence replication (3SR)
iv) Nucleic Acid sequence Based Amplification
(NASBA) is used to amplify RNA ( by J
Compton) in 1991.

Cont…
 Labeling DNA- In three ways-
1) Using primers with fluoroscent dyes.
2) Using fluoroscently labeled deoxynucleotides.
3) Using a fluoroscent intercalating dye to bind to DNA.
• Detection of STR segment –
• Is similar to that of RFLP
• But here capillary electrophoresis is used.
• Detection is by LASER which detects fluoroscent
dye and forms a peak for each window.
• This is called an Electropherogram.
• Data analysis is done by Gene mapping software
IPD-X.

Cont…
 Advantages of STR profiling
1) Is possible on degraded samples due to smaller
size of alleles. (10-500)
2) PCR amplification is possible due to smaller
size of STR segments.
- However if length of RFLP segment is less than
1000 bp PCR amplification can be used. (AFLP)
3) STR are highly polymorphic 5-10 alleles per
locus.
4) Automated procedure.

Cont…
5) Multiplex amplification – amplification of multiple
loci simultaneously.
- Number of independent loci detected in an
assay is called its multiplex ratio.
6) DNA from multiple contributors
- In RFLP only possible with use of SLP.

Interpretation of DNA profiling

 Refers to a forensic analysis of VNTR loci that can be
amplified using PCR
Salient Features
 AmpFLP refers to amplification of VNTR loci <1000 bp
in size by using PCR, its a cross between RFLP & PCR
Amplified Fragment Length Polymorphism

Cont…
 Procedure
 DNA from the sample is digested with restriction
endonucleases
 Subset of DNA fragments is selected for PCR
amplification & visualization. Staining is done by
silver
 An allelic ladder comprisisng of DNA fragments that
represent common alleles, is used to identify DNA
fragments
 This technique was developed by Key Gene in early
1990’s (Netherlands)

 Advantage
 Requires less DNA than traditional RFLP method
 Faster than RFLP
 Can be analyzed in a multiplex fashion along with
amelogenin locus
 Better resolution (as polyacrylamide gel having
smaller pores is used for separation of fragments)
With advent of multiplex STR systems, AmpFLP is rarely
used now.
Amplified Fragment Length Polymorphism

 Refers to the study & analysis of forensically important
loci on the Y-chromosome.
Salient Features
 Peculiarities of Y-chromosome
 Contains the fewest number of genes of any
chromosome.
 Half of it contains heterochromatin (about 30 million
bp)
 Genes on Y-chromosome are critically important in
sexual development
 Only chromosome that is passed from father to son
(not to daughters) & mother has no role in
transmission
Y-chromosome Profiling (YCP)

Cont…
 Procedure
 Same as STR (except that - only Y-chromosome
STRs are used.
 Between 9 & 17 Y-STR markers are usually studied
& analysis is done through multiplex kits.
 Less than 0.1 ng DNA is required.

 Usefulness in forensic work
 Crime scene sample left by a culprit will usually be
informative when typed with Y-specific marker as
majority of violent crimes are committed by males
 Mixed samples (male assailant & female victim
DNAs) as in rape cases – these markers will give
specific information on the assailant.
 Gang rape – semen from multiple males
 Paternity – Y-chromosome is identical in father & son,
so this would be helpful where the paternity of a son
is in question
 Ethnicity – Y-STRs & Y-SNPs provide info on ethnic
origin of a male
Y-chromosome Profiling (YCP)

Cont…
 Drawbacks-
 Even when a crime sample matches the Y-
STR profile of a suspect, patrilineal relative of
the suspect can not be excluded.

Application of DNA profiling
 A. Disputed paternity :
Such questions arise under following
circumstances
(i) When the child is born in lawful marriage, but
the husband denies that he is the father.
(ii) When a child is born out of lawful marriage, and
the mother accuses a certain man of being the
father of child and the man denies the
accusation.
(iii) Suppositious child.
(iv) Suits for nullity of marriage.

Cont…
Procedure -
 Parents - 5 ml of venous blood is taken from
mother and alleged (putative) father and placed in
EDTA tube. Neither party should have had a
blood transfusion within 3 months.
 Infant – For taking blood, should not be <2 m;
preferably >6 m.
- 1 ml blood is taken in a EDTA tube by
venepuncture, or prick (ear or heel).

Cont…
B. Extortion
(1) DNA profiling done from saliva samples (from
envelops sent as extortion letters) can be
matched with that of accused.
(2) Similar profilings done from the material on face
masks, gloves,nasal secretions and saliva from
cigarette butts.

Cont…
C. Homicide
(1) Blood – DNA profiling done from blood (found
on weapon or on clothes of accused) can be
matched with that of victim.
(2) Tissue – found on bullet recovered from scene
of crime.
(3) Hair roots – Similar matching from hair on a
weapon with that of victim.

Cont…
D. Identification
(1) Crime scenes -
 Crucial DNA evidence may by left at crime scenes
which may be matched to those to potential
suspects.
 Besides usual biological materials eg : semen,
blood, urine and feces, unusual trace evidences
that can lead to positive identification are a single
human hair, lip cells left on a beer can and saliva
on envelope flaps and cigarette butts etc.

Cont…
(2) Mutilated remains : as in accidents, bomb blasts,
burnt bodies,mass disasters, other catastrophes and
putrefied bodies.
 DNA profiles from such remains may be compared
with previous profiles.
 DNA profiles of the deceased (during his life) may be
prepared by taking cells of the deceased from
toothbrush, combs etc which the deceased had been
using.
 If DNA profiles cannot be prepared from such
material, profiles of close relatives such as parents,
children, siblings etc might be taken, which will also
be useful.

Cont…
E. Sexual crimes
(1) Identification of accused from DNA profile of
accused.
F. OTHER :
(1) Authenticate consumables such as caviar and wine
(2) Environmental forensics - Detect bacteria and other
organisms
that may pollute air, water, soil, and food
(3) Justice - Exonerate persons wrongly accused of
crimes
(4) Wildlife forensics - Identify endangered and
protected species as an aid to wildlife officials (could
be used for prosecuting poachers)

Cont…
(5) Immigration - some visa applications may
depend on proof of relatedness.
(6) Organ donation - Match organ donors with
recipients in
transplant programs
(7) Pedigree tracing.

Limitations of DNA profiling
(1) Twins - DNA profiling of identical twins is same
(fingerprints even in identical twins are different)
(2) Expensive; elaborate equipment. Thus facility
available at
limited places
(3) Contamination of samples can give wrong
results
(4) Older DNA profiling technologies are more time
consuming(RFLP).

Cont…
(5) Ethical –
- Invasion of privacy - Holding a person’s DNA profile
on record is violation of that person’s DNA
‘ownership’.
- Deletion of records - If a person has been proved
innocent after DNA profiling, he has a right to demand
removal of his DNA information from police data
bases, but this is rarely done.
- Illegal sharing of information - DNA information can
be shared by police with others (eg medical
researches, drug companies) without the individual’s
consent.

Cont…
(6) Sabotage - DNA evidence is easily planted at a
crime scene.
(much more difficult or even impossible with
fingerprints)
(7) In blood and bone marrow transfusion – DNA
profile of donor will be generated and he may be
indicted for a crime he did not commit.

DNA Database
 A DNA database or DNA databank is a database
of DNA.
 Salient features :
(1) A DNA database is used much like a fingerprint
database in identifying criminals, but can also
be used in the analysis of genetic diseases, or
genealogy held electronically in the DNA
database.

Cont…
(3) DNA Databases around the world -
 US – Has the largest DNA database in the world
(CODIS)
 UK - The United Kingdom National DNA
Database (2nd largest)
 Australia - The National Criminal Investigation
DNA Database(NCIDD)
 Canada - The National DNA Data Bank (NDDB)
 India – No similar DNA database till date.

Cont…
(4) Genomic sequences in DNA databases :
 Full genomic sequence is not recorded - Only
patterns of STRs.
 Different databases record different STRs. There is no
unanimity.
(5) Privacy issues :
 Such databases pose ethical issues, eg threats to an
individual’s civil liberties.
 DNA databases may contain person’s health-related
data, including markers that identify various genetic
diseases etc.
 This is regarded as an invasion to privacy.

Cont…
A. Combined DNA Index System (CODIS)
DNA database funded by the United States Federal Bureau
of Investigation (FBI).
 Salient features:
❏ The DNA database in the USA (CODIS) came into
existence
following the enactment of the DNA Identification Act, 1994.
❏ CODIS identifies 13 STR markers, (plus AMEL to
determine sex). Sometimes referred to as 13-CODIS.
❏ DNA profiles created by federal, state, and local crime
laboratories laboratories in the US are collectively
computerized.
❏ The profiles can be searched and matched with those of
suspects in a matter of minutes.

Cont…
B. DNA database in India
❏ India currently does not have a DNA database of
criminals.
❏ The Government of India, through a Gazette
Notification has created a DNA Profiling Advisory
Committee (DPAC).
❏ The CDFD in Hyderabad has prepared the “DNA
Profiling Bill 2007”, which is pending in
Parliament.

CASE -STUDY
1) Goutam Kundu vs State of West Bengal –
- DNA test should not be used as routine as it
shall be against the public policy to bastardising
the child
- Only when very strong proof of non-access
between spouse is present.
- Not to use test as a scope for reapproachment,
specially when there are no eligations by
husband in divorce petition.

Cont…
2) Kamti Devi vs Poshi Ram –
- Here respondant was the husband of the
appelant.
- Appelant gave birth to a child after 15 years.
- Respondent filed a civil suit that he is not the
father of the child as he has no access during the
period child would have been concieved.
- Refused 112 of the Evidence Act - Birth during
marriage, conclusive proof of legitimacy.

Cont…
- However on re evaluation of evidence the first
appelant Court found that respondent succeeded
in discharging the burden by proving that he had
no access to the mother of the child over very
long strech of time, covering the relevant period.
- It allowed the appeal and decreet the suit.
- High Court dismissed appeal on the grounds that
the question involved therein was merely a
question of fact.

Cont…
- The supreme court stated that it may look hard
from the point of husband to bear the fatherhood
of a child of which he is innocent.
- But law leans in favour of innocent child from
being bastardizing.
- So, burden of plantiff husband should be higher
than the standard of preponderance of
probabilities.

Cont…
- In the present case the first appellate court which
is the final fact finding court, after evaluating the
entire evidence, came to the conclusion the
plantiff husband had no opportunity whatsoever
to have relation with the defendant mother.
- The finding thus reached by the

Cont…
 In the present case the first appellate court which
is the final fact finding court, after evaluating the
entire evidence, came to the conclusion the
plantiff husband had no opportunity whatsoever
to have liaison with the defendant mother.
 The findings thus reached by first appellate court
could not be interfered within a second appeal as
no sustantial question of law would have flowed
out of such a finding.

Cont…
3) Nandlal Wasudeo Badwaik vs Lata Nandlal
Badwaik –
- Supreme court was in favour of husband that a
husband cannot be made to be bear a burdern of
fatherhood when the DNA test disapproved
parenity.
4) Dipanwita roy v/s Ronobrotoroy –An attempt
was made to balance the two extremes of
possible judgement.

Cont…
 If she chose not to submit herself and the child for
such a test the, court could drawn an adverse
inference against her in terms of section 114 of
the Evidence Act that would have a bearing on
the infidality issue but would not disturb the
conclusive presumption of legitimacy under
section 112 of Evidence act.

Cont…
5) Narayandutt Tiwari vs Rohit Shekhar
- Use of reasonable force by taking police
assistance if not willing.
- Not for old person.
6) Dharamdeo Yadav vs State of UP –
- The Supreme Court underscored the need pf
precaution during collection, packaging and
forwarding of DNA samples.

Cont…
7) Kamalnantha vs State of Tamil nadu –
- Rape 13 girls- inmates of asheam- some were
made to do with fear of hurt or death.
- Dr. Lalji Singh Deputy Director, CCMB
Hyderabad, opined that when DNA profile dead
fetus, Aruljioth and Pramanand were matched,
the dead fetus was there child.
- Dr. Wilson J wall’s evidence was no accepted in
court.

Cont…
8) Nirmaljit Kaur vs State of Punjab.
9) The People vs Ornethal J Simpson.
10) Colin Pitchfork [1988] :
 The first person in the world to be criminally
prosecuted on DNA
 evidence.
 ❏ He raped and murdered Linda Mann in 1983 and
Dawn
 Ashworth, in 1986 (both 15 y old girls) in the English
 countryside.
 ❏ Initially the prime suspect was a local 17-year-old
youth,
 Richard Buckland, a person of low intelligence and
sexual
 fetishes. He revealed knowledge of Ashworth’s

10) Colin Pitchfork [1988] :
 The first person in the world to be criminally
prosecuted on DNA evidence.
 He raped and murdered Linda Mann in 1983 and
Dawn Ashworth, in 1986 (both 15 y old girls) in
the English countryside.
 Initially the prime suspect was a local 17-year-old
youth, Richard Buckland, a person of low
intelligence and sexual fetishes. He revealed
knowledge of Ashworth’s body, and admitted the
crime under questioning, but denied the first
murder.

Cont…
- Jeffreys compared semen samples from both
murders against a blood sample from Buckland
which conclusively proved that both girls were
killed by the same man, but not the suspect.
- Thus Buckland became the first person to have
his innocence established by DNA profiling.

AIMS AND OBJECTIVES
 To know various psychoanalytical tests in crime
detection.
 To know various ethical issues concerned to
psychological tests in crime detection.
 To know the laws related to psychoanalytical
tests.
 To know the rights of accused.
 To know the judicial admissibility of
psychoanalytical tests.

INTRODUCTION
 The Polygraph (Lie detector), The P300 (Brain
Mapping) and The Narco analysis (Truth Serum)
are the three main scientific tools of interrogation.
 Used for extracting confessions from suspects of
criminal and terrorist avtivities.
 These psychoanalytical tests are also used to
interpret the behavior of suspected crimnals and
corroborate the observations of investigating
agencies.

 Functional magnetic resonance imaging (fMRI) is
another technology that is being used in the USA
as a lie detector by intelligence agencies despite
of its unreliability and probability of abuse.
 These tests are also known as Detection of
Deception Tests (DDT).

Polygraph or Lie Detector test
1. Principle – It is based on principle that when a
person is asked a series of questions, fake
answers will produce distinctive physiological
measurements.
 It is also known as Psychophysiological
Detection of Deception (PDD).
 Physiological changes in blood pressure, heart
rate, respiratory rate, breathing rhythm,
temperature and skin conductivity.

Speakin
g lie
Fear
Sympathetic
activity
Heart rate Blood
pressure
Respiratory
rate
Sweating
Skin
conductivi
ty

2. Procedure – Two types of polygraphs analog
and digital (computerized) are available.
 Analog devices make actual ink tracings while
digital devices make inkless tracings of above
parameters.
 Stoelting polygraphs which are both analog
and digital are used commonly.

 Physiological activities are measured by following
procedure –
a. Respiratory rate – Two pneumographs, rubber
tubes filled with air are put around the subject’s
chest and abdomen.
 When chest and abdomen expand, air inside tubes
is displaced.
 In analog device, the displaced air acts on a
bellows, that contracts when the tube expands.
 This bellow is attached to a mechanical arm, which
is connected to an ink filled pen that makes mark on
scrolling paper as subject breathes.
 In digital device, trasducers are used to convert the

b. Blood pressure / Heart rate – A blood pressure
cuff is placed around the subject’s arm.
 Tubing runs from cuff to polygraph.
 As blood pumps through arm it makes sound.
 Changes in pressure caused by sound displace
the air in tubes, which are connected to a bellow,
which moves the pen.
 In digital device transducers convert these signals
to electrical signals.

c. Galvanic skin resistance (GSR) – This is also
called electro-dermal activity.
 Measures sweat on fingertips.
 Person sweats more when under stress.
 Fingerplates called galvanometers, are
connected to of the subject’s fingers.
 These plates measure skin’s ability to conduct
electricity.
 Wet skin, more electrical.

Steps –
 Pre test interview – to gain preliminary
information to use as “control questions” later.
 Explanation of test – The interpreter explains
about the procedure of polygraph test.
- Emphasize on that it detect lies and it is important
to answer truthfully.
- Questions will be suggestive in nature.
- Answers should be in ‘Yes’ or ‘No’.

 Consent of the subject to be examined – consent
of the person is must for the test to be performed.
 Actual test –
i) Irrelevant question (IR) – having no relation with
the incident.
eg. What is your name? or Is your name Ram?
ii) Probable lie or Control questions (CQ) – that
most people will lie about. Eg. Have you ever stolen
money?
iii) Relevant questions (RQ) – having direct relation
with the incident.
 Usually not more than10 questions are asked to a
person at any single sitting.

3. Results and interpretation – If response to RQ
> CQ, person is experiencing fear and thus
lying.
- Among all responses, the response to change in
respiration and galvanic skin reaction are
assumed to be more reliable.
- Post test questions – if response to RQ < CQ,
the investigator attempts to elicit admissions
during post test interview.
- Eg. “Your situation will only get worse if we don’t
clear this up”.

 Drawbacks and Reliability –
- The principle behind this test is questionable as
the measured parameters changes in arousal
state are not necessarily triggered by lying.
- They could be triggered by nervousness, anxiety,
fear, confusion, hypoglycemia, depression,
psychosis, substance induce or withdrawl and
other emotions.
- Arousal state also been attributed to the way
questions are asked by investigating officer.

 At same time it is not difficult to beat the
polygraph tests by trained person, who is able to
control or suppress his/her arousal symptoms
through relaxation exercise, yoga, meditation, etc.
 Use of beta blockers may impair the test
outcomes.
 Persons not suitable for polygraph test –
- Mentally ill person.
- Over reactive, restless and non co-operative
person.
- Person suffering from respiratory and
cardiovascular disease.
- Drug addicts.

 Reliability - Due to above mentioned reasons the
reliability of this test is questionable.
 Main reason due to which results of this test are
disallowed are
- Human facet of polygraph examination
- Subjective nature of the test.
 There are -
- False positive – The response of truthful person
is determined to be deception.
- False negative – The response of a deceptive
person is determined to be truthful.

 American Medical Association Council on
Scientific Affairs states that the us e of control
question technique in criminal cases is time
honoured and is much scientific study.
 Classification of guilty can be made 75% - 97%
accuracy.
 As false positive rate is often sufficiently high,
which makes difficult to use this test as sole
arbiter of guilt or innocence.
 But it can be used in criminal investigation as
evidence or another source of information to
guide the investigation with keeping its limitations
in consideration.

 Use of polygraph test for personnel screening is
gaining popularity but adequately validated.
 Few limited studies suggest no greater accuracy
for this type of testing than for control question
polygraph testing used in criminal cases.
 Use of this test to control theft and fraud
associated with employment has never been
measured.
 Its impact on employee morale and productivity
has not been determined.

 According to Charles Honts, a psychology
professor, polygraph interrogation gave a high
rate of false positives on innocent people.
 In 2001, William G. Iacono concluded that
although the CQT may be useful as an
investigative tool and aid to induce confessions,
it doesn’t pass the criteria of a scientifically
credible test.
 CQT theory is based on weak and unimaginable
assumptions indicating that –
a) It is biased against innocent individuals.
b) It can be beaten simply by artificially augmenting

 Both of above conclusions are supported by
published research findings in best social science
journals.

Narcoanalysis (Truth serum)
 It is interrogation of a suspect by investigating
agencies after inducing narcosis.
 J. Stephen Horsley of England first described
narcoanalysis in a book in 1943.
1. Principle – person lies using his imagination,
requires full consciousness.
- By inducing semiconscious state,capacity of
inventing lies diminished.
- In this state it is presumed that his answers are
spontaneous would be restricted to facts he is
already aware of.

2. Procedure –
- The team conducting narcoanalysis consists of –
i) a physician – certifies fitness of person before
and after test.
ii) an anesthetist – modulates the depth of
anaesthesia required depending upon the
quantum of information to be obtained and
monitors various stages of anaesthesia
iii) a clinical/ forensic psychologist – interacts
with the person in trance and gives reports
along with videotapes to the courts on behalf of
the team.

 Commonly used drugs –
i) Anticholinergics –
- 3-quinuclidinyl benzilate – an odorless
incapacitating agent used in military. Also known
as BZ. It is related to atropine, scopolamine and
hyoscyamine
- Scopolamine
ii) Hypnotics –
- Barbiturates – Sodium amytal (intermediate
acting), Sodium pentothal (ultrashort acting)
- Also known as Amytal interview.

 Anaesthetist injects 3 grams of Sodium Pentothol
or Sodium Amytal + 3000 ml of distilled water.
 The dose depends on sex, age, health and physical
condition of subject.
 Wrong dose can lead to coma or death.
 Drug depresses CNS, lowers blood pressure and
slows heart rate, putting person into a hypnotic
trance, resulting in lack of inhibition.
 Subject interrogated in presence of doctor.
 Revelations made during this stage are recorded in
both video and audio cassettes.

 This procedure is conducted -
- in government hospital
- after courts order is passed
- consent of the subject is also required.
 In absence of consent of the subject for narco
analysis or similar tests, where the same is
ordered by the court, the larger interest should
outweigh the individual liberties and fundamental
rights.

 The judicial sanction for these methods rest on the
argument that protection of Article 20(3) does not
apply at the investigative stage.
 Drawbacks –
i) Main drawback is some persons are able to retain
their ability to deceive even in hypnotic state, while
others can become extremely suggestible to
questioning.
- This is worrying, since investigators may frame
questions in a manner that may prompt incriminatory
response.
ii) Adverse effects of thiopentone sodium include
laryngeal spasm.

Brain Mapping ( Brain
fingerprinting)
 It is a forensic science technique that determines
whether specific information ( regarding a crime)
is stored in a subject’s brain.
 It is scientifically known as Memory and
Encoding Related Multifaceted
Electroencephalographic Response
(MERMER).
 Invented and developed by Lawrence Farwell of
US in 1990’s.

 Principle –
i) Storage of information in brain
ii) EEG responses to crime related information
-
- If information related to crime is shown to the
subject there will be relevant EEG waves that
would be detected.
- EEG response to an image, sound, etc. is known
as event related potential (ERP).
- Memory is an integral part of ERP.
- So if a person is shown a familiar image, EEG
shows memory related wave in ERP.

 These memory related ERPs are called P300
because delay between stimulus and response is
300 ms.
 So it is also known as P300 test.
ii) Procedure –
 The subject to be tested wear a special headband
with electronic sensors (electro-cap) that
measure the EEG from several locations on
scalp.
 He thenshown various stimuli consisting of words,
phrases or pictures.

 Stimuli are of three types
a) Irrelevant – unknown to subject.
b) Target – relevant and known to subject.
c) Probe – stimuli are relevant to the investigated
situation and that the subject denies knowing.
- Probe stimuli contain information that is known
only to the perpetrator and the investigators.

iii) Results and interpretation –
- If the subject has killed the victim, his brain would
recognize scene of crime and weapon.
- Even if he consciously denies information his
EEG would show memory related P300 waves.

iv) Drawbacks
 However, this measures only the memory or
knowledge of the crime scene and nothing else.
 So for instance, a by-stander who witnessed a
murder could potentially be implicated as
accused if the test reveals that the said person
was familiar with information related to the same.
 Similar findings will be there if little is known
about crime scene by portrayal in media.
 Hence, this test can’t be used to procsecute an
accused.
 But can be used by an innocent as an ‘alibi’ by
proving that he/she does not have any memory
about the crime on this test.

Legal and Ethical Issues
1. Legal Issues –
 ‘Right against self- incrimination’ enumerated
in Article 20(3) of the Indian Constitution, which
states that no person accused of an offence shall
be compelled to be a witness against
himself/herself, is violated.
 ‘Right to life and personal liberty’ enumerated
in Article 21 of the Indian Constitution has been
judicially expanded to include a right against
cruel, inhuman or degrading treatment, is also
violated.

 Section 161(2) of CrPC is also violated as it
states that no person accused of any offence
shall be compelled to be a witness against
himself.

2. Ethical Issues – following are the ethical issues
involved in conducting DDTs :
i) Whether tests stuck in controversies regarding
their scientific authenticity should be considered
as genuine scientific tools of interrogation.
ii) Whether an individual can be forced to undergo
tests that have been considered undependable
and discarded by various courts in many
countries.
iii) Whether narco analysis which has potential to
cause life threatening situations should be
conducted.

iv) Whether medical practitioners can be a part of
the team that conducts the interrogation.
- The involvement of doctors in the course of
investigation in criminal cases has long been
recognized as an exception to the physician-
patient privilege.
- In Indian context, legal provisions for directing
medical examination are an example of the same.
- A reasonable limitation on the forensic uses of
medical expertise is the fact that testimonial acts
such as results of a pscychiatric examination
cannot be used as evidence without subject’s

These pscychoanalytical procedures are
considered as torture because -
 When a person undergoes a narco analysis test,
he/she is in a semiconscious state and does not
remember the revelations made in a drug-
induced state.
 In case of polygraph test and BEAP test, the test
subject remains fully conscious during tests but
does not immediately know the nature and
implications of results derived from the same.

 Revelations made during these tests can be self
incriminatory or can be used against some other
individual.
 The realization of such consequences can lead to
mental pain or suffering.
 Also tests results could also support the theories
or suspicion of the investigators in a particular
case.
 For a person in custody, such confirmations could
lead to specifically targeted behavior such as
physical abuse.

1. The World Medical Association Declaration
of Tokyo (1975) –
- The doctor must in no way, for any reason, take
part in the practice of torture or other form of
cruel, inhuman or degrading procedures as the
doctor’s role is to alleviate the distress of his/her
fellow persons and, no motive whether personal,
collective or political shall prevail against this
higher purpose.
- The doctor shall not provide any premises,
instruments, substances or knowledge to facilitate
the practice of torture or other forms of cruel,
inhuman or degrading treatment or diminish the
ability of the victim to resist such treatment.

- For the purpose of this declaration, torture is
defined as the deliberate, systematic or wanton
infliction of physical or mental suffering by one or
more persons acting alone or on orders of any
authority, to force another person to yield
information, to make confession, or for any other
reason.

Judicial Admissibility
 The admissibility of these tests in court is always
controversial.
 It is stated in Section 24, 25 and 26 of Indian
Evidence Act, 1872 that the confession made by
a person under police custody could not be
admitted as evidence.
 In Dinesh Dalmia vs State –
- In 2006, Madras High Court held that subjecting
an accused to narco analysis is not tentamount to
testimony by compulsion.
- The court said about accused “ he may be taken
to the laboratory for such tests against his will,
but revelations during such tests is quite
voluntary.

- Court said that conducting narco analysis test
does not violate Article 20(3) per se.
- Only after conducting the test, if the subject
divulges or reveals information which is
incriminatory, then it will be hit by Article 20(3).
- So, other information revealed during test can
help the investigation.
- Thus, there is no reason why we should prohibit
such a test on grounds of unconstitutionality.

 In Multi-crore-rupee fake stamp paper case
popularly known as Telgi case -
- In 2004, the Bombay High Court ruled that
subjecting an accused to certain tests like
narcoanalysis does not violate the fundamental
right against self – incrimination as statements
made under such tests are not admissible as
evidence.
- The Bombay High Court in a significant verdict in
case of Ramchandra Reddy and Ors v. State of
Maharashtra upheld the legality of the DDTs.

- The court also upheld the special court order by
special court in Pune allowing SIT to conduct
scientific tests on accused in Telgi case including
the main accuse Abdul Karim Telgi.
- It stated in its verdict that evidence procured under
truth serum is also admissible.
- In course of judgement ‘statement’ is made before
police and ‘testimony’ is made under oath in
court.
- The Judges , Justice Palshikar and Justice Kakade,
said that lie detector and brain mapping did not
involve any ‘statement’ and in statement in narco

 Also revelations made during narcoanalysis have
been very useful in solving sensational cases of
Mumbai serial train blasts, Delhi blast, Malegaon
and more recently in Hyderabad.
 In Santokben Sharma Bhai Ladeja v. State of
Gujrat, the Gujrat High Court held that
narcoanalysis test is conducted under supervision
of doctors and proper care is taken and there is
consent.
- So element of risk is minimal. Risk in fact is a part
of life and involves in most of human activities.
- Thus these tests cannot be condemned.

 Dr. Rajesh Talwar and another v. CBI through
its director and other commonly known as
Arushi Murder case –
- In this a 14 yr girls was found to be dead in the
home on 16/05/2008.
- Report was by parents of Arushi.
- Domestic servant, Hemraj was also missing and
was the prime suspect.
- But after 2 days he was found dead on the
terrace of the house of Arushi.

- The parents of Arushi were arrested by police.
- There were three more accused.
- Narcoanalysis, polygraph and brain mapping
tests were performed on accused person.
- The narco test cracked the case and played
crucial role in finding accused.
- It was pleaded before court not take reports of
these tests as evidence.

 Polygraph test conducted in a rape case, 2005– In
Banglore, one Pratibha Shrikanth, a female BPO
employee was raped and murdered.
- The charge was framed against a driver hired by the
company.
- The driver was subjected to polygraph, brain mapping
and narco analysis tests.
 Polygraph test conducted in Shivani Bhatnagar
murder case – The Indian Express journalist was
murdered at her East Delhi apartment on 23rd January
1999.
- In this case murder charges was framed on a
Haryana Cadre I.G. Police Mr. R.K. sharma and five
other accused persons.

- The polygraph test were conducted on Shivani’s
husband, brothers, sister and brother-in-law.
 Nithari case –
- Businessman Moninder Singh Pandher and his
domestic servant Subhash Koli were accused
murdering 31 children.
- In scientific tests the servant Subhash Koli
admitted serial killing of missing children.

 Polygraph test conducted on Mumbai serial
killer –
- One Ravindra Kantrole, a suspect of serial killing
of seven people in South Mumbai in Marine Drive
and Azad Maidan Police Station, was subjected to
scientific tests.
- During which he confessed his crime.
- A higher version of brain mapping that is Brain
Electrical Oscillation Signature (BEOS) was used.
- Polygraph and BOES were conducted at
Maharashtra FSL and narcoanalysis was
conducted at Banglore FSL on 14th Februry 2007.

 Recent Supreme Court judgement on DDTs –
- The Supreme Court judgement on May 5, 2010 in
case of Selvi v. State of Karnataka , regarding
involuntary administration of DDT for the purpose of
improving investigation efforts in criminal case was
questioned as it violates-
i) Right against self incrimination – Article 20(3)
ii) Right to life and personal liberty – Article 21
- So the DDTs are constitutionally impermissible and
cannot be forced.
- Even if answers are obtained during voluntary
process it is not admissible in court.

 In M.P. Sharma v. Satish Chandra case the
Apex court observed that since the words used in
Article 20(3) were “to be a witness) and not “to
appear as a witness” the protection is extended
to compelled evidence obtained outside the
Courtroom.
 As DDTs have raised serious ethical concerns
and medical personelles involved in their
conduction National Human Rights Commission
has laid guidelines regarding administration of
Polygraph test.

 Guidelines of NHRC for administration of
Polygraph test –
 NHRC on 12 November 1999 adopted a set of
guidelines.
 These are –
 No lie Detector Test should be administered
without the consent of the accused. Option should
be given to the accused as to whether he wishes
to avail the test.
 If the accused volunteers for the tests, he should
be given access to a lawyer. The Police and the
lawyer should explain the physical, emotional &
legal implications of such a test to him.

 The consent should be recorded before a Judicial
Magistrate.
 During the hearing before the Magistrate, the
accused should be duly represented by a lawyer.
At the hearing, the person should also be told in
clear terms that the statement that is made shall
not be a ‘confessional’ statement to the
Magistrate but will have the status of a statement
made to the police.

 The Magistrate shall consider all factors relating to
the detention including the length of detention &
the nature of interrogation.
 The actual recording of the Lie Detector Test shall
be done in an independent agency (such as a
hospital) & conducted in the presence of a lawyer.
 A full medical & factual narration of the manner of
information received must be taken on record.
 These guidelines of the Commission were
circulated to the Chief Secretaries & DGPs of
States as well as Administrators & IGPs of UTs by
th

Reference :
 1) Textbook of Medical Jurisprudence and
Toxicology, MODI
 2)Textbook of Forensic Medicine and Toxicology,
Dr.ANIL AGGRAWAL.

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