oForensic Criminology
Notes Criminology:
Criminology is the scientific
study of crime, criminals, criminal behavior, and efforts to regulate crime.
Forensic Criminology:
The term Forensic Science is
defined as “The application of science to those civil and criminal laws that
are enforced by the police agencies in a criminal justice system. Forensic
Criminology explores the depth of crime, its causes and criminal motivation to
address legal and investigative questions.
This distinction involves an
appreciation of applied criminology.
As a form of macro-analysis: it tends to involve the nomothetic
(group) examination of systems, processes, and their relationships.
Alternatively, forensic criminology.
As a form of micro-analysis:
it tends to involve the idiographic (individual) examination of one or more
related cases and consideration of its internal issues.
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History and Origin:
The concept of forensic science is not new in
the criminal investigation system. It dates back thousands of years. Argentina
was the first country to incorporate forensic evidence for a criminal
investigation in 1902.
Sir William Herschel was one of
the first to advocate the use of fingerprinting in the identification of
criminal suspects. By the late 1700s, forensic science was being used as a
factor to determine guilt or innocence in major criminal cases, including murder
charges. One of the primary functions of forensic science is to study DNA, the
genetic coding found on all living things.
By the end of the 20th century,
forensic scientists had a plethora of high technology tools for analyzing
evidence from DNA analysis to digital fingerprinting techniques with computer
search capabilities.
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Evidence:
Types of Evidence:
Following are the types of evidence:
1.
Fingerprint evidence
2.
Trace evidence
3.
DNA/Biological Evidence
4.
Weapons Evidence
5.
Drug evidence
6.
Natural/synthetic Material Evidence
7.
Generic objects evidence
8.
Digital evidence
9.
Other items
1. Fingerprint Evidence: Fingerprint
evidence is used to determine if someone is connected to the crime or a part of
the crime scene. It also helps the investigator to track the record of the
criminal’s previous arrest or conviction.
2. Trace Evidence: Trace evidence is a
general term for small, sometimes microscopic, material. It covers such small
evidence like fibers, hair, dust, building materials that it can be transferred
without being noticed.
3. DNA /Biological Evidence: The two most
common types of biological evidence are saliva and blood. Blood evidence comes
in the form of wet blood (e.g., a tube of blood from an autopsy) or swabs of
bloodstains collected at crime scenes. Other types of biological evidence
include hair, seminal stains, urine, and perspiration. In each case, the motive
is to provide sufficient samples of biological evidence to allow DNA profiling.
4. Weapons Evidence: It consists of
firearms (handguns, rifles, assault weapons, etc.), ammunition (e.g., spent
casings, fired projectiles, bullet fragments, and unfired bullets), gunshot
residue (GSR) tests, and knives. The purpose of a GSR kit is to determine
whether an individual was close to a firearm at the time of discharge.
5. Drug Evidence: Drug evidence includes
drugs (e.g., marijuana, cocaine, methamphetamine, and others), and drug
paraphernalia (pipes, spoons, etc.) found at a scene.
6. Natural/Synthetic Materials: Natural
and synthetic materials include clothing, bed and bath material, carpet
cuttings, plastic, paper, and metal objects.
7. Generic Objects: Generic objects
include vehicles, bicycles, containers, doors, wood, and concrete, etc.
8. Digital evidence: It involves the
evidence found in computers and digital storage media like pen drives, hard
disks, etc. Its major objective is identifying, preserving, recovering,
analyzing, and presenting facts and opinions about digital information.
9. Other Items: Other items are a catchall
category for evidence that does not fit in any of the above categories.
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Methods:
DNA Forensics:
The most effective way to find out who
committed the crime is through DNA analysis. This method comes into play when a
criminal leaves behind hair, skin, blood or anything else from his body. The
DNA in the sample is compared with the DNA from potential suspects to find the
criminal. In some cases DNA evidence is useless because sample sizes are too
small or there are no matches among the suspects.
Sources of DNA Evidence:
DNA is a deoxyribose nucleic acids are
composed of nucleotide units. The biological material used to determine a DNA
profile include blood, semen, saliva, urine, feces, hair, teeth, bone, tissue
and cells. DNA can be found in either the nucleus of the cell (the center of
the cell), or the mitochondria outside of the nucleus.
Samples that May be Used:
Investigators collect items that
could have been touched or worn by persons involved in a crime. The following
items may contain DNA material: Masks, Hats, Gloves, Clothing, Tools, and
Weapons. Sexual assault evidence kits, Underclothes, Bedding. Dirty laundry,
Fingernail scrapings, Cups/bottles, Cigarettes, Toothpicks, Toothbrush, Facial
tissue, Hairbrush, Eyeglasses, Condoms, Tape, Ligatures(rope, wire, cords),
Stamps or envelopes The best evidence occurs when a person’s DNA is found where
it is not supposed to be.
For example:
Consider a breaking-and-entering
that occurred in a residential area. Near the point of forced entry, a knit cap
was found which the homeowners confirm was not theirs. Several head hairs were
recovered from the inside, one of which had a root with tissue attached, which
made it possible to obtain a DNA profile. The DNA profile was used to identify
the perpetrator.
As technology advances, forensic
scientists are able to analyze smaller and smaller biological samples to
develop a DNA profile.
For example:
If a person touched an object or
weapon, skin cells may have been left behind. This low-level DNA is sometimes
referred to as “touch DNA”. It can even be collected from a victim’s skin or
bruises where they were handled roughly. Low-level DNA samples may be helpful
when examining evidence where it would be difficult to retrieve
fingerprints—such as textured surfaces on gun handles or automobile dashboards.
However, not all jurisdictions have the capability to process this evidence.
To compare the victim’s or
suspect’s DNA profile to the recovered crime-scene DNA, the laboratory will
need to have their known biological samples available for a side-by-side
comparison. These known samples are called reference samples. In some jurisdictions,
a DNA sample is routinely taken from an arrestee during the process of booking
and fingerprinting. However, this is an evolving area of law and states vary in
their laws governing the collection of DNA from arrestees. Sometimes a court
order is required to retrieve a reference from a person of interest. Reference
samples are always collected from victims unless they choose not to cooperate
with the investigation; in that case, a court order might be required.
In addition to unknown and reference samples, elimination
samples are often collected from consensual sex partners and others, such as
first responders, crime scene personnel and analysts working the case so they
can be excluded from the investigation. It is important that biological
evidence be properly collected and preserved as it can easily degrade when
exposed to heat or humidity. Storing evidence in cool environments is
preferred; however, research has shown that room temperature conditions are suitable
for storing dried stains as long as the humidity is controlled. Liquid samples
should be transported in refrigerated or insulated containers.
Ø Who Conducts DNA Analysis?
DNA analysts working in
laboratories that participate in the National DNA Index System (NDIS) and/or
are accredited by a recognized organization must meet specific educational and
training requirements. At a minimum, a bachelor’s degree in biology, chemistry,
or a forensic science-related area is required. In addition, the analyst should
have successfully completed nine hours of coursework at the undergraduate or
graduate level covering the following subject areas: biochemistry, genetics,
molecular biology, as well as coursework or training in statistics and/or
population genetics, as it applies to forensic DNA analysis. The specialists
who conduct DNA analysis in the laboratory are referred to by several different
titles, including: Crime Laboratory Analyst, Forensic Examiner, Forensic
Scientist and Forensic Laboratory Analyst.
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Ø How and Where DNA Testing is performed?
Prior to performing DNA analysis
at the laboratory, initial testing is often conducted at the crime scene to
determine the type of biological material in question. Screening for the
presence of biological materials may also be conducted in the laboratory to
determine if a specific biological fluid may be present. Most biological
screening tests are presumptive in nature and do not specifically identify a
bodily fluid. Most DNA samples submitted to a laboratory undergo the following
process:
1.
Extraction is the process of releasing the DNA
from the cell.
2.
Quantitation is the process of determining how
much DNA you have.
3.
Amplification is the process of producing
multiple copies of the DNA in order to characterize it.
4.
Separation is the process of separating
amplified DNA product to permit subsequent identification.
5.
Analysis & Interpretation is the process of
quantitatively and qualitatively comparing DNA evidence samples to known DNA
profiles.
6. Quality
Assurance is the process of reviewing analyst reports for technical accuracy.
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Ø How to Comparing Profiles
against a Central Database?
To enable profiles to be searched
against a large, national database, Pakistan need to create the National DNA
Index System (NDIS). This national database is part of the Combined DNA Index
System (CODIS) that enables law enforcement agencies throughout the nation to
share and compare DNA profiles to help investigate cases.
Once a laboratory enters a case
into CODIS, a weekly search is conducted of the DNA profiles in NDIS, and
resulting matches are automatically returned to the laboratory that originally
submitted the DNA profile. CODIS may have three levels of operation:
Local DNA Index System(LDIS)
Provincial DNA Index System
(PDIS)
National DNA Index System
(NDIS)
The NDIS databases contain DNA
profiles from:
1.
Convicted Offenders - DNA profiles of
individuals convicted of crimes
2.
Arrestees - profiles of arrested persons (if
state law permits the collection of arrestee samples)
3.
Forensic unknowns - DNA profiles of unknown
individuals developed from crime scene evidence, such as semen stains or
blood
4.
Missing Persons - contains DNA reference
profiles from missing persons
5.
Biological Relatives of Missing Persons -
contains DNA profiles voluntarily contributed from relatives of missing
persons
6.
Unidentified Humans (Remains) - contains DNA
profiles developed from unidentified human remains
7.
NADRA database
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Computer Forensics:
Computer forensics is also known
as digital or cyber forensics. It is a branch of digital forensic science.
Using technology and investigative techniques, computer forensics helps
identify, collect, and store evidence from an electronic device. Computer forensics
is a field of technology that uses investigative techniques to identify and
store evidence from a computer device. Often, computer forensics is used to
uncover evidence that could be used in a court of law. Computer Forensics Lab
experts forensically analyses all types of data stored in computer hard drives,
USB memory sticks, cloud spaces, social media, cameras and mobile phones to
find relevant digital evidence.
TYPES of Computer Forensic:
1.
Disk
Forensics: It deals with extracting raw data from the primary or secondary
storage of the device by searching active, modified, or deleted files.
2.
Network
Forensics: It is a sub-branch of Computer Forensics that involves
monitoring and analyzing the computer network traffic.
3.
Database
Forensics: It deals with the study and examination of databases and their
related metadata.
4.
Malware
Forensics: It deals with the identification of suspicious code and studying
viruses, worms, etc.
5.
Email
Forensics: It deals with emails and their recovery and analysis, including
deleted emails, calendars, and contacts
6.
Memory
Forensics: Deals with collecting data from system memory (system registers,
cache, RAM) in raw form and then analyzing it for further investigation.
7.
Mobile
Phone Forensics: It mainly deals with the examination and analysis of
phones and smartphones and helps to retrieve contacts, call logs, incoming, and
outgoing SMS, etc., and other data present in it.
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Ø Define Characteristics of
Computer Forensic?
1.
Identification:
Identifying what evidence is present, where it is stored, and how it is stored
(in which format). Electronic devices can be personal computers, Mobile phones,
PDAs, etc.
2.
Preservation:
Data is isolated, secured, and preserved. It includes prohibiting unauthorized
personnel from using the digital device so that digital evidence, mistakenly or
purposely, is not tampered with and making a copy of the original evidence.
3.
Analysis:
Forensic lab personnel reconstruct fragments of data and draw conclusions based
on evidence.
4.
Documentation:
A record of all the visible data is created. It helps in recreating and
reviewing the crime scene. All the findings from the investigations are
documented.
5.
Presentation:
All the documented findings are produced in a court of law for further
investigations.
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Ø Discuss procedure and
phases of computer forensics?
The procedure starts with
identifying the devices used and collecting the preliminary evidence on the
crime scene. Then the court warrant is obtained for the seizure of the evidence
which leads to the seizure of the evidence. The evidence are then transported
to the forensics lab for further investigations and the procedure of
transportation of the evidence from the crime scene to labs are called chain of
custody. The evidence are then copied for analysis and the original evidence is
kept safe because analysis are always done on the copied evidence and not the
original evidence.
The Nine Phases of Digital Forensics
There are nine steps that digital
forensic specialists usually take while investigating digital evidence.
1.
First
Response As soon as a security incident occurs and is reported, a digital
forensic team jumps into action.
2.
Search
and Seizure The team searches devices involved in the crime for evidence
and data. Investigators seize the devices to make sure the perpetrators can’t
continue to act.
3.
Evidence
Collection After seizing the devices, professionals collect the data using
forensic methods to handle the evidence.
4.
Securing
of the Evidence Investigators store evidence in a safe environment. In the
secure space, the data can be authenticated and proved to be accurate and
accessible.
5.
Data
Acquisition The forensic team retrieves electronically stored information
(ESI) from the devices. Professionals must use proper procedure and care to
avoid altering the data and sacrificing the integrity of the evidence.
6.
Data
Analysis Team members sort and examine the authenticated ESI to identify
and convert data that is useful in court.
7.
Evidence
Assessment Once ESI is identified as evidence, investigators assess it in
relation to the security incident. This phase is about relating the data
gathered directly to the case.
8.
Documentation
and Reporting This phase happens once the initial criminal investigation is
done. Team members report and document data and evidence in accordance with the
court of law.
9.
Expert
Witness Testimony An expert witness is a professional who works in a field
related to the case. The expert witness affirms that the data is useful as
evidence and presents it in court.
The analysis is then done on the
copied evidence for suspicious activities and accordingly, the findings are
documented in a nontechnical tone. The documented findings are then presented
in a court of law for further investigations.
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Ø Write down Some Tools
used for Investigation?
Tools for Laptop or PC –
a)
COFFEE – A suite of tools for Windows developed
by Microsoft.
b)
The Coroner’s Toolkit – A suite of programs for
Unix analysis.
c)
The Sleuth Kit – A library of tools for both
Unix and Windows.
Tools for Memory :
a)
Volatility
b)
WindowsSCOPE
Tools for Mobile Device :
a) MicroSystemation XRY/XACT
APPLICATIONS
a)
Intellectual Property theft
b)
Industrial espionage
c)
Employment disputes
d)
Fraud investigations
e)
Misuse of the Internet and email in the
workplace
f)
Forgeries related matters
g)
Bankruptcy investigations
h)
Issues concerned the regulatory compliance
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Ø Write down Common
computer forensics techniques?
When conducting an investigation
and analysis of evidence, computer forensics specialists use various
techniques; here are a few examples:
1.
Deleted
file recovery. This technique involves recovering and restoring files or
fragments deleted by a person—either accidentally or deliberately—or by a virus
or malware.
2.
Reverse
steganography. The process of attempting to hide data inside a digital
message or file is called steganography. Reverse steganography happens when
computer forensic specialists look at the hashing of a message or the file
contents. A hashing is a string of data, which changes when the message or file
is interfered with.
3.
Cross-drive
analysis. This technique involves analyzing data across multiple computer
drives. Strategies like correlation and cross-referencing are used to compare
events from computer to computer and detect anomalies.
4.
Live
analysis. This technique involves analyzing a running computer's volatile
data, which is data stored in RAM (random access memory) or cache memory. This
helps pinpoint the cause of abnormal computer traffic.
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Ø What are the Advantages of Computer
Forensics?
To produce evidence in the court,
which can lead to the punishment of the culprit.
It helps the companies gather
important information on their computer systems or networks potentially being
compromised.
Efficiently tracks down cyber
criminals from anywhere in the world.
Helps to protect the
organization’s money and valuable time.
Allows to extract, process, and interpret the factual
evidence, so it proves the cybercriminal action’s in the court.
Ø What are the Disadvantages of Computer
Forensics?
Before the digital evidence is
accepted into court it must be proved that it is not tampered with.
Producing and keeping electronic
records safe is expensive.
Legal practitioners must have
extensive computer knowledge.
Need to produce authentic and
convincing evidence.
If the tool used for digital
forensics is not according to specified standards, then in a court of law, the
evidence can be disapproved by justice.
A lack of technical knowledge by
the investigating officer might not offer the desired result.
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Methods Using Insects
Forensics often refer to insects
at the crime scene to determine specific information, such as the time a murder
victim died. Forensic entomologists use two main methods to evaluate
approximate time of death in, one method looks at what type of insects are on
and in the decomposing body and the other uses the life stages and life cycles
of certain insects to establish how long a body has been dead.
Forensic Entomology:
Forensic entomology is the study
of insects/arthropods in criminal investigation on the possibilities of using
forensic data based on insects and their larvae morphology, growth histories,
species distribution and toxic contents in their tissue in criminal
investigation.
When were initially investigator used
Insects for criminal investigation?
The first recorded incident where
insects were used in a criminal investigation was in 13thcentury China as
described in Sung Tzu's book called The washing away of wrongs. When a farmer
was found murdered in a field with a sharp weapon, all the suspects were told
to place their sickles on the ground. Only one sickle attracted blow flies to
the trace amount of blood hidden to the naked eye which resulted in the
confession by the murderer.
The first application of forensic
entomology in a modern court house was in 18th-century France where
entomological data was admitted as proof for acquitting the current occupants
of the residence from where the skeletonized remains of a child were found. In
the 18th century Yovanovich and Megnin's evaluation of the insect succession on
corpses established the science of forensic entomology.
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Arthropodes and their association with
postmortem Changes of the human body:
As soon as death occurs, cells
start dying and enzymes start digesting the cells inside out in a process
called autolysis. The body starts decomposing. Bacteria present in the
gastrointestinal tract start destroying the soft tissue producing liquids and gases
like hydrogen sulphide, carbon dioxide, methane, ammonia, sulfur dioxide and
hydrogen.
The volatile molecules called
apeneumones escaping from the decomposing body attract insects. Researchers are
able to isolate the volatile chemicals released at different stages of
decomposition of the body. The volatile molecules released during each stage
can modify the insect behavior. Based on the studies done by Crag et al., in
1950 it was found that putrative sulfur-based compounds were responsible for
initially attracting the flies to the decomposing carcass but egg laying or
oviposition of the flies are induced by ammonium-rich compounds present on the
carrion.
According to Smith (1986) four categories of insects can be
found on decomposing carrion:
Ø Necrophagous species feeding on the
carrion;
Ø Predators and parasites feeding on the
necrophagous species: this group also contains schizophagous species which
feed on the body first and which become predaceous on the later stages;
Ø Omnivorous species feeding on the
carrion (meat, flesh, tissues) and other arthropods like ants, wasps and some
beetles;
Ø Other species like springtails and
spiders which use the corpse as an extension of their environment. The first
two groups are found to be more important for the purpose of forensic
entomology. They are mainly from the species of the order Diptera (flies) and
Coleoptera (beetles). The succession waves in which the arthropods colonize the
carrion depends on the state of decomposition of the carrion.
Insects mostly involved in the forensic investigations are
true flies or Diptera. The predominant species in this order are Calliphoridae
(blow flies) , Sacrophagidae (flesh flies) and Muscidae (house flies).
Calliphoridae (blow flies), Sacrophagidae (flesh flies) may arrive within
minutes following death.
• Muscidae (house flies) delay
colonization until the body reaches bloat stages of decomposition. The adult
Muscidae are 8-12 mm long. Their thorax is gray, with four longitudinal dark
lines on the back. The whole body is covered with hair-like projections.
• Calliphoridae adults are commonly shiny
with metallic coloring, often with blue, green, or black thoraxes and abdomen.
• Sarcophagidae are medium-sized flies
with black and gray longitudinal stripes on the thorax and checkering on the
abdomen.
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Stages to determine the decomposing body
According to the studies done by K. Tullies and M. L Goff
on exposed carrion in a tropical rainforest, it was found that the
decomposition process was best divided into five stages on the basis of
physical appearance of carcasses (skeleton, Shell, bodies), internal
temperatures and characteristic of insect populations:
1.
Fresh stage (Days 1-2): which begins at the
moment of death and ends when the bloating (swelling) of the carcass is
observed. Even though autolysis occurs at this stage gross morphological
Changes do not occur at this point.
2.
Bloated stage (Days 2-7): Putrefaction
(decomposition) begins at this stage. Gases produced by the metabolic
activities of anaerobic bacteria cause an inflation of the abdomen and the
carcass forming a balloon-like appearance during the later part. by the fourth
day, first- and early secondinstar or larval stages Diptera were present. By
the beginning of Day 2, several predators of Diptera larvae were also recovered
from the carcasses.
3.
Decay stage (Days 5-13): Abdominal wall is
penetrated, resulting in the deflation (decrease) of the carcass and ending the
bloated stage, the internal temperature rises to 14 degrees above the ambient
temperature followed by a drop signifying the end of the decay stage. Decaying
odors are high during increased temperatures and drop with a fall in
temperature. There is a steady decrease in the weight of the carcass by 10th
day. There is a conversion of carcass biomass to dipteran larval biomass. The
larvae subsequently depart from the carcass to pupate (Third generation of
inactive stage of insect’s development).
4.
Post-decay stage (Days 10-23): The post-decay
stage begins when most of the Diptera larvae leave the carcass, leaving behind
bones, cartilage (A tough, flexible tissue that lines joints and gives
structure to the nose, ears, larynx, and other parts of the body), hair, small
portions of tissue, and a large amount of wet, viscous material known as
byproducts of decay (BOD). The BOD is the major site of arthropod activity
during this stage.
5.
Remains stage (Days 18-90+): This stage is
characterized by bones with little cartilage remaining and the BOD has dried
up. The transition from post-decay to remains stage is gradual, with declining
adult and larval Diptera populations.
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Steps in estimating the postmortem index
with insect larvae:
The insect larvae present on the
dead body can provide evidence for the estimation of PMI up to one month.
Correct species identification is the initial step. Different species differ in
their growth rates and maturation. For estimating the PMI, age of the larvae
has to be determined. By measuring the length or dry weight of the oldest
larvae and comparing it with the reference data, age of the larvae can be
estimated.
The rate of development of the
larvae is dependent on the surrounding ambient temperatures. Each stage of
development has its temperature requirement hence each species has its own
defined number of accumulated degree days or accumulated degree hours to complete
its development.
Once the thermal history of the
larvae is obtained, it can be compared with temperatures at the death scene and
PMI can be estimated. The first-generation adult flies can also be used to
determine the age. They can be identified by the shriveled wings, and tiny
abdomen with dull grey color. When insects colonizing the carrion in a
particular area is known, an insect colonizing succession model can also be
used to estimate the PMI.
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Forensic Anthropology:
Forensic anthropology is the
method of looking at bones to determine the way a victim died. Forensic
anthropology is usually used for human studies, such as looking at how a group
died during specific historical time periods based on the bones. In criminal
investigations, this method comes into play when the evidence consists of
skeletal remains of a victim rather than a body.
Forensic anthropology has many
disciplines, one of which is forensic osteology. Forensic anthropology is
mainly for the study of basic identification like estimating age, ethnic group,
sex, and stature from the skeletal remains.
Forensic anthropology has already
made progress in its field. The advancement in forensic anthropology is only
possible and dependent on the advancement of the older technique and by
creating new techniques based on the type of cases. Forensic anthropology plays
a major role in identifying and establishing the identity in an investigation.
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Methods used in forensic anthropology
investigation
In forensic anthropology, exact
knowledge related to sex of the unidentified remains can be represent and offer
to identity to it through molecular examination. Whether the tooth or the bone
needs to be analyzed during the examination of skeletal remains. As DNA test is
costly as well as destructive also, these are decisive and influences the
outcome of the analysis. For Human Identification from the skull is generally
classified as:
Reconstruction Method: Reconstruction method proposes only
possibilities and probabilities without certainty of as many criterions of
individualization from the skull, like ethnic group, age, sex, stature, etc.,
as possible. The process of recreating the face of an unidentified individual
from their skeletal remains through an amalgamation of artistry, forensic
science, anthropology, osteology, and anatomy. Types: a) Modeling clay method
b) Computer software programs c) Manual sketching method.
Comparative Method: Comparative method gives a high degree of
reliability and precision where the photographs and radiographs are used for
evaluation with the skull. Types: a) Metric measurements b) Superimposition:
Negative SI Video SI. Evidential value of superimposition technique in the
court of law is corroborative
Radiography: Sex determination is one of the most confused puzzles,
which needs to be solved by radiographic examination. Sexual dimorphism
represented by the skeletal system determines the accuracy with which the
skeleton can be identified. There are different morphological features between
males and females. For example, in negroids, left side frontal sinuses gave
accuracy in sex determination by 60%
Radiocarbon dating: It is one of the most used methods for
determining the age of the skeleton. The amount of Carbon-14 obtained from the
skeleton remains or any other part helps in determining the age of the remains.
X-Ray fluorescence (XRF): X-Ray fluorescence is used for the
determining of mineral content of bone such as Zn, Pb, and Fe. The presence of
these elements at different quantity helps in determination of diet of an
individual and the abundance of these elements in the bones also helps in
determining the area to which an individual belongs. The main advantage of this
technique is that this technique takes very less time for examination.
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Techniques used to analyzed by Forensic
Anthropologist
Anthropologists use a variety of
techniques to analyze human remains and record their observations. For example,
the bones are typically photographed and X-rayed. Some remains may undergo CT
scanning or be examined with high-powered microscopes. These techniques provide
detailed information about remains without altering them while providing a
visual record. DNA analysis may be used to help establish identity. This type
of testing is most often used in modern forensic case work, but mitochondrial
DNA in bones and teeth can be used to confirm relationships of old remains with
deceased or living descendants. Other chemical analyses, such as those
involving isotopes, can provide information about the age of bones and a
person’s diet. The techniques they use to answer questions in criminal cases
can be applied to skeletons of any age, modern or ancient. The stages of growth
and development in bones and teeth provide information about whether the
remains represent a child or adult. The shape of pelvic bones provides the best
evidence for the sex of the person. Abnormal changes in the shape, size and
density of bones can indicate disease or trauma. Bones marked by perimortem
injuries, such as unhealed fractures, bullet holes, or cuts, can reveal cause
of death. The trained anthropologist is also able to identify skeletal clues of
ancestry. Even certain activities, diet, and ways of life are reflected in
bones and teeth.
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