PERSONAL

IDENTIFICATION
TECHNIQUES

LESSON TWO: PERSONAL IDENTIFICATION TECHNIQUES

Personal identification is defined as establishing the identity of an individual. The need for personal
identification arises in natural mass disasters like earth quakes, tsunamis, landslides, floods etc., and in man-
made disasters such as terrorist attacks, bomb blasts, mass murders, and in cases when the body is highly
decomposed or dismembered to deliberately conceal the identity of the individual

The need to identify the dead is obvious for social and medico-legal purposes. Various techniques of
biological anthropology are employed in the process of identifying the individuals from the bones or the body
parts. The identification of the dead from the bones/ body parts in a legal setting forms an essential component
of forensic anthropology. The foremost task in achieving the personal identification is to establish whether the
skeletal remains are human or not. If the remains belong to a human being, then various anthropological
techniques can be used to identify the dead. The ‘big fours’ of personal identification are determination of age,
sex, stature and ethnicity. These form the features of ‘tentative identification

I. FORENSIC ANTHROPOLOGY

Forensic anthropology, application of physical anthropology to legal cases, usually with a focus on the
human skeleton. Forensic anthropology uses the techniques of physical anthropology to analyze skeletal,
badly decomposed, or otherwise unidentified human remains to solve crimes. Forensic anthropologists can
assess the age, sex, and unique features of a decedent and are invaluable in documenting trauma to the body
and estimating how long a corpse has been decomposing. Forensic anthropologists work closely with
individuals in law enforcement and medical science—and especially with specialists in ballistics, explosives,
pathology, serology (the study of blood and bodily fluids), and toxicology—and are often expert witnesses in
murder trials.

When human remains or a suspected burial are found, forensic anthropologists are called upon to
gather information from the bones and their recovery context to determine who died, how they died, and how
long ago they died. Forensic anthropologists specialize in analyzing hard tissues such as bones. With their
training in archaeology, they are also knowledgeable about excavating buried remains and meticulously
recording the evidence.
 How do investigators and scientists tell if a bone or skeleton belongs to a man or a woman? The clues
lie in the bones themselves.

A skeleton's overall size and sturdiness give some clues. Within the same population, males tend to
have larger, more robust bones and joint surfaces, and more bone development at muscle attachment sites.
However, the pelvis is the best sex-related skeletal indicator, because of distinct features adapted for
childbearing. The skull also has features that can indicate sex, though slightly less reliably.

The differences between a male and female pelvis are compared below”

Pelvic Inlet

Male: narrower, heart-shaped

Female: open, circular

Sciatic Notch

Male: narrower

Female: broader

Pubic Bones

Male: narrower sub-pubic angle where the two bones meet

Female: wider sub-pubic angle where the two bones meet

Hip Bones

Female: more outwardly flared

Fact: Sex-related skeletal features are not obvious in children's bones. Subtle differences are detectable, but
they become more defined following puberty and sexual maturation.

I.A. The human Skeletal System

The skeletal system includes all of the bones and joints in the body. Each bone is a complex living
organ that is made up of many cells, protein fibers, and minerals. The skeleton acts as a scaffold by providing
support and protection for the soft tissues that make up the rest of the body. The skeletal system also provides
attachment points for muscles to allow movements at the joints. New blood cells are produced by the red bone
marrow inside of our bones. Bones act as the body’s warehouse for calcium, iron, and energy in the form of
fat. Finally, the skeleton grows throughout childhood and provides a framework for the rest of the body to grow
along with it.

The skeletal system in an adult body is made up of 206 individual bones. These bones are arranged
into two major divisions: the axial skeleton and the appendicular skeleton. The axial skeleton runs along the
body’s midline axis and is made up of 80 bones in the following regions:
  Skull  Auditory  Sternum
 Hyoid ossicles  Vertebral
 Ribs column

The appendicular skeleton is made up of 126 bones in the following regions:

o Upper limbs o Pelvic girdle  Pectoral (shoulder)

o Lower limbs girdle

II. FORENSIC ODONTOLOGY

Forensic odontology is the application of dental science to legal investigations, primarily involving the
identification of the offender by comparing dental records to a bite mark left on the victim or at the scene, or
identification of human remains based on dental records.

Criminals have been known to leave bite mark impressions at the crime scene, whether it be in food,
chewing gum or, more commonly, on the victim. When a bite mark is discovered, numerous steps should be
taken. Once the mark has been sufficiently photographed, a saliva sample is taken from the area for potential
DNA evidence. Casts or moulds can then be made. If another bite impression is found elsewhere or if a teeth
impression is taken from a suspect, a comparison can be made.
 In identifying human remains based in their teeth, dental records should ideally be obtained and
compared to those of the unidentified body. If this is not possible, other clues in the teeth may be useful. Tooth
eruption is linked to a certain extent with age, giving a possible rough estimation of the victim. When working
with a young victim, the stage of development of a child’s teeth may be used to determine their age, though
this can only be an estimate. The state and wear patterns of an individual’s teeth may give insight into the
person’s age, diet, and dental history, as well as personal habits such as pipe-smoking and eating disorders.

However the reliability of forensic odontology has been called into question on numerous occasions.
The skin itself is not a good medium for dental impressions, often having a number of irregularities that will
cause distortion. Bite marks can be altered through stretching, movement, or change in environment after the
bite. There is also no set standard by which to analyse and compare bite marks.

Aside from criminal cases, forensic odontologists and dentists are greatly involved in the identification
of victims of mass disasters. Dental records in particular are beneficial in identifying such victims.

II.A The Human Dental Structure

Below is an image of an Adult dental structure:

Below is an image depicting a child dental structure:

III. DNA ANALYSIS
Data analysis can be used in old or unsolved crimes or to identify human
remains. The availability of parental DNA samples might allow identification of a body when
conventional means (physical appearances, dermatoglyphic fingerprints, dental charts)
have been unsuccessful. Dissimilar DNA profiles will exclude a relationship. Teeth are
important evidentiary material in forensic cases, since they are more resistant to
postmortem degradation and extreme environmental conditions. Teeth are also easy to
transport and serve as a good source of DNA. Comparisons of antemortem dental records
with skeletal remains have long provided a useful means of identifying individuals, even in
a mass grave. In affluent societies, dental records may be decisive in determining the
identity of individual victims. However, in less affluent communities, which are more likely
to be involved in human rights abuses associated with mass murder, dental records are
unlikely to be available. In this situation, the only option for identification might be DNA
analysis.

There are many examples in the media of crimes that have been solved decades
after they were committed because evidentiary material has been re-examined using DNA
profiling for the first time, or more sensitive DNA techniques have become available. For
cold crimes to be solved, there needs to be cooperation between law enforcement agencies,
the forensic laboratory and a centralized DNA database. Statutes of limitation that were
imposed because of the knowledge that with time witness accounts may no longer be
accurate may need to be reassessed because DNA testing can still provide answers after
many decades.