FORENSIC SCIENCE
‘AN ART OF FACIAL RECONSTRUCTION’
Presented by: Asmita A.Inamdar USN: 2GI06MCA08 M.C.A 2nd SEM And Veena S.Mithare USN: 2GI06MCA58 M.C.A 2nd SEM
M.C.A 2nd Semester 1
Forensic Science
ABSTRACT
Facial reconstruction for postmortem identification of humans from their skeletal remains is a challenging and fascinating part of forensic art. The former look of a face can be approximated by predicting and modeling the layers of tissue on the skull. This work is as of today carried out solely by physical sculpting with clay, where experienced artists invest up to hundreds of hours to craft a reconstructed face model. Remarkably, one of the most popular tissue reconstruction methods bears many resemblances with surface fitting techniques, thus suggesting the possibility of a transfer of the manual approach to the computer. In this paper, we present a facial reconstruction approach that fits an anatomy-based virtual head model, incorporating skin and muscles, to a scanned skull using the data on skull / tissue relationships. The approach has many advantages over the traditional process: a reconstruction can be completed in about an hour from acquired skull data; also, variations such as a slender or a more obese build of the modeled individual are easily created. Last not least, by matching not only skin geometry but also virtual muscle layers, head model is generated that can be used to form facial expressions.
M.C.A 2nd Semester 2
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INDEX
Sl.no Contents Page no. 1. Definition 01 2. History 01- 02 3. Types of identification 02- 03
4. Types of reconstructions 03- 05 4.1 Two-dimensional reconstructions 4.2 Three-dimensional reconstructions 4.3 Superimposition 5. Technique for creating 3-D reconstruction 05- 08 5.1 3-D clay reconstructions 5.2 computerized 3-D facial reconstruction
6. Problems with facial reconstruction 08- 09 6.1 Insufficient tissue thickness data 6.2 Lack of methodological standardization 6.3 Subjectivity 7. Facial reconstructions and the media 09- 10
8. Future developments 11 9. Subdivisions of forensic science 11-12 10. Indian institutions offering forensic science 12-13 10. Conclusion 13 11. References 13
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Forensic Science
DEFINITION –
Forensic facial reconstruction (or forensic facial approximation) is 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. It is easily the most subjective - as well as one of the
most controversial - techniques in the field of forensic anthropology. Despite this
controversy, facial reconstruction has proved successful frequently enough that
research and methodological developments continue to be advanced.
1. HISTORY-
Welcker (1883) and His (1895) were the first to reproduce three-dimensional
facial approximations from cranial remains. Most sources, however, acknowledge
His as the forerunner in advancing the technique. His also produced the first data
on average facial tissue thickness followed by Kollmann and Buchly who later
collected additional data and compiled tables that are still referenced in most
laboratories working on facial reproductions today.
Facial reconstruction originated in two of the four major subfields of
anthropology. In biological anthropology, they were used to approximate the
appearance of early hominid forms, while in archaeology they were used to
validate the remains of historic figures. In 1964, Gerasimov was probably the first
to attempt paleo-anthropological facial reconstruction to estimate the appearance
of ancient peoples.
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Although students of Gerasimov later used his techniques to aid in criminal
investigations, it was Wilton M. Krogman who popularized facial reconstruction’s
application to the forensic field. Krogman presented his method for facial
reconstruction in his 1962 book, detailing his method for approximation. Others
who helped popularize three-dimensional facial reconstruction include Cherry
(1977), Angel (1977), Gatliff (1984), Snow (1979), and Iscan (1986).
2. TYPES OF IDENTIFICATION -
There are two types of identification in forensic anthropology:
circumstantial and positive.
Circumstantial identification-
It is established when an individual fits the biological profile of a
set of skeletal remains. This type of identification does not prove or verify
identity because any number of individuals may fit the same biological
description.
3.2 Positive identification-
It one of the foremost goals of forensic science, is established when a
unique set of biological characteristics of an individual are matched with a set
of skeletal remains. This type of identification requires the skeletal remains to
correspond with medical or dental records, unique ante mortem wounds or
pathologies, DNA analysis, and still other means. Facial reconstruction
presents investigators and family members involved in criminal cases M.C.A 2nd Semester 5
Forensic Science
concerning unidentified remains with a unique alternative when all other
identification techniques have failed. Facial approximations often provide the
stimuli that eventually lead to the positive identification of remains.
4. TYPES OF RECONSTRUCTIONS -
There are two main methods used in forensic facial approximation: two-
dimensional and three-dimensional.
4.1 Two-dimensional reconstructions-
Two-dimensional facial reconstructions are hand-drawn portraits
based on radiographs, ante mortem photographs, and the skull. This method
usually requires the collaboration of an artist and a forensic anthropologist.
Recently developed, the F.A.C.E. and C.A.R.E.S. computer software
programs quickly produce two-dimensional facial approximations that can be
edited and manipulated with relative ease. These programs help speed the
reconstruction process and allow subtle variations to be applied to the
drawing.
Figure 1- 2-D facial reconstruction.
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4.1 Three-dimensional reconstructions-
Three-dimensional facial reconstructions are either: 1) sculptures
(made from casts of cranial remains) created with modeling clay and other materials or 2) high-resolution, three-dimensional computer images. Like two- dimensional reconstructions, three-dimensional reconstructions usually require both an artist and a forensic anthropologist. Computer programs create three-dimensional reconstructions by manipulating scanned photographs of the unidentified cranial remains, stock photographs of facial features, and other available reconstructions. These computer approximations are usually most effective in victim identification because they do not appear too picturesque or too artificial.
Figure 2- 3-D facial reconstruction.
4.2 Superimposition-
Superimposition is a technique that is sometimes included among the methods of forensic facial reconstruction. It is not always included as a technique because investigators must already have some kind of knowledge M.C.A 2nd Semester 7
Forensic Science
about the identity of the skeletal remains with which they are dealing (as
opposed to 2D and 3D reconstructions, when the identity of the skeletal
remains is generally completely unknown). Forensic superimpositions are
created by superimposing a photograph of an individual suspected of
belonging to the unidentified skeletal remains over an X-ray of the
unidentified skull. If the skull and the photograph are of the same individual,
then the anatomical features of the face should align accurately.
5. TECHNIQUE FOR CREATING 3-D FACIAL RECONSTRUCTION –
5.1 3-D clay reconstructions-
When skeletal remains are found, and the victim remains unidentified after
traditional means of identification fail, investigators may call upon the forensic
artist to utilize the three-dimensional facial reconstruction technique. The three-
dimensional process is initiated by placing the skull on a workable stand, where
the skull can easily be tilted and turned in all directions. The skull must be
positioned in the Frankfort Horizontal position. By utilizing proper tissue depth
data determined by race, gender, and age. Artificial eyes are placed in the skull’s
eye sockets, centered and at the proper depth. The tissue markers are glued
directly onto the skull. Clay will be systematically applied directly on the skull,
following the skull's contours; paying strict attention to the applied tissue
markers. Various measurements are made, and logged, to determine nose
thickness/length, mouth thickness/width, and eye placement. Information such as
geographic location of where the deceased lived, his or her lifestyle, and the M.C.A 2nd Semester 8
Forensic Science various information provided to the artist by the Forensic Anthropologist and other professionals, is heavily relied upon when completing the reconstruction.
Hair is accomplished by means of a wig, or by applying clay to represent hair.
Various items (props), such as glasses, clothing, hats, etc. may be applied to better accentuate the features of the individual. Upon completion, the sculpture is photographed. All procedures are documented and working notes collected. When executed properly, this technique is proven to have a high success rate.
Frontal View of Skull Completed Reconstruction Reconstruction Colorized
Figure 3 Figure 4 Figure 5
5.2 Computerized 3-D Facial Reconstruction-
Most recently, computerized methods for 3D facial reconstruction have been developed (Ubelaker and O'Donnell 1992, Vanezis et al. 1989, Shahrom et al. 1996, Miyasaka et al. 1995). These methods employ computer programs to transform laser-scanned 3D skull images into faces. Although the results are more reproducible than sculpted reconstructions, some subjectivity can remain in the
'pegging' of a composite facial image onto the digitized skull matrix. The use of
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Forensic Science such a standardized image will reduce the influence of the individual shape of each skull, which is after all fundamental to the person's appearance.
Computerized methods may be repeatable, fast and precise, but as long as they employ the old data, the quality of the reconstruction will be undermined.
Here a Cyberware 3030 RGB color laser scanner and Silicon Graphics
Indy™ computer to capture 3D images of the skull. As the platform rotates
(Figure 5) a 'wire frame' matrix is generated (Figure 6). Computed tomography
(CT) scanning permits more accurate measurement of tissue depths (Figure 7).
Large samples of tissue depth measurements can be collected, with associated attributes of age, sex, build and, where appropriate, ethnic group. A pilot study on the collection of tissue depth measurements from CT scans has been carried out by one of our team (Nelson 1996). Digitized images of facial features not predicted by the skull contours (nose, eyes and mouth) must be added by separate means to generate a wire frame face (Figure 8), onto which color and texture can subsequently be rendered (Figure 9). If necessary, a skull can be reconstructed
'virtually' from the separately scanned parts.
Figure 5 Figure 6 Figure 7 Figure 8 Figure 9
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6. PROBLEMS WITH FACIAL RECONSTRUCTION-
6.1 Insufficient tissue thickness data-
There are multiple outstanding problems associated with forensic facial reconstruction. The most pressing issue relates to the data used to average facial tissue thickness. The data available to forensic artists are still very limited in ranges of ages, sexes, and body builds. This disparity greatly affects the accuracy of reconstructions. Until this data is expanded, the likelihood of producing the most accurate reconstruction possible is largely limited.
6.2 Lack of methodological standardization-
A second problem is the lack of a methodological standardization in approximating facial features and individuating characteristics. Forensic anthropologists and artists have published individual techniques used in their own practices. However, a single, official method for reconstructing the face has yet to be recognized. This also presents major setback in facial approximation because facial features like the eyes and nose and individuating characteristics like hairstyle - the features most likely to be recalled by witnesses - lack a standard way of being reconstructed. Without consistency and a standard method for approximating these features, it will remain very difficult for forensic reconstruction to earn wide recognition as a legitimate form of forensic identification.
6.3 Subjectivity- M.C.A 2nd Semester 11
Forensic Science
Reconstructions only reveal the type of face a person may have exhibited
because of artistic subjectivity. The position and general shape of the main facial
features are mostly accurate because they are greatly determined by the skull, but
subtle details like certain wrinkles, birthmarks, skin folds, the shape of the nose
and ears, etc, are unavoidably speculative because skeletal remains leave no
evidence of their appearance. The success of reconstruction depends as much
upon the circumstances pertaining to the subject under investigation as it does
upon the accuracy of the technique.
7. FACIAL RECONSTRUCTION AND THE MEDIA
The facial reconstruction of Tutankhamen as shown on the cover of
National Geographic in 2005.
Due to the recent rise in popularity of television shows (e.g. CSI: Crime
Scene Investigation, CSI: Miami, CSI: NY, NCIS, Bones, and the UK program
M.C.A 2nd Semester 12
Forensic Science
Meet the Ancestors) and feature films concerned with criminal investigations,
forensics, and law enforcement, the presence of forensic facial reconstructions in
the entertainment industry and the media has also increased.. In reality, facial
reconstructions are widely used as a last resort to stimulate the possibility of
identifying a victim. Interest in discovering and identifying “lost” and/or
significant historical figures has also increased the presence of forensic facial
reconstruction among the public consciousness. For example, the facial
reconstruction of Egypt’s King Tut made the June 2005 cover of National
Geographic Magazine. Casdon Toys has produced a line of at-home facial
reconstruction toys featuring Julius Caesar, King Tut, Queen Nefertiti, and
Neanderthal Man. The popular CSI: Crime Scene Investigation television show
has also produced an at-home facial reconstruction kit.
8. FUTURE DEVELOPMENTS-
Currently, data collection from CT scans is a laborious and time-
consuming process of amassing a series of point-to-point measurements. The
automated capture of 3D data from CT scans is an imminent proposition, but will
not be cost effective for facial reconstruction in the near future. Methods for
ageing a reconstruction or for making comparisons with digitized missing person
databases are also far off. It has been suggested that an eventual understanding of
the developmental genetics of facial growth may allow forensic or ancient DNA
to be used to inform reconstructions. This imaginative idea somewhat downplays
the importance of epigenetic factors in physiological development – and the M.C.A 2nd Semester 13
Forensic Science
influence of ageing, build and a plethora of environmental influences upon one's
appearance! Research on the psychology of face recognition will be applicable,
and portable laser scanning equipment is shortly to be made available – raising
the possibility that computerized facial reconstruction could be used in sensitive
human rights work in the field.
9. SUBDIVISIONS OF FORENSIC SCIENCE-
1. Forensic accounting is the study and interpretation of accounting evidence.
2. Forensic anthropology is the application of physical anthropology in a legal
setting, usually for the recovery and identification of skeletonized human
remains.
3. Forensic archaeology
4. Forensic computing
5. Forensic economics is the study and interpretation of economic damage
evidence to include present day calculations of lost earnings and benefits, the
lost value of a business, lost business profits, lost value of household service,
replacement labor costs and future medical care costs.
6. Forensic engineering studies the causes of failure of devices and structures.
7. Forensic epistemology deals with philosophical knowledge in a legal setting,
typically for understanding behavior of states.
8. Forensic linguistics deals with anything in the legal system that requires
linguistic expertise.
9. Forensic Medicine M.C.A 2nd Semester 14
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10. Forensic psychology and forensic psychiatry deal with the legal aspects of
human behavior.
11. Forensic science using science to create an argument in places such as court.
12. Forensic biology performs serological and DNA analysis of physiological
fluids for the purpose of identification and individualization.
13. Forensic serology is the application of the study of blood, semen, saliva and
other body fluids to legal matters.
14. Digital forensics deals with the digital evidence (e.g. e-mail, photos stored on a
computer).
10. INDIAN INSTITUTIONS OFFERING FORENSIC SCIENCE-
1. Dr. Harisingh Gour University, Sagar, MP
2. University of Madras (Chennai), Chennai
3. University of Mysore, Karnataka
4. Osmania Universty, Hyderabad
5.Lok Nayak Jayaprakash Narayan National Institute of Criminology and
Forensic Science
6. School of Engineering and Applied Sciences (SEAS),(Rai University)
7.Bureau of Police Research & Development, Govt. of India, New Delhi
11. CONCLUSION-
Facial reconstruction is destined to remain an art, albeit an increasingly
informed one. Nevertheless, a forensic facial reconstruction has value in M.C.A 2nd Semester 15
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potentially allowing the exclusion of a particular individual as the unidentified
subject.
12. REFERENCES-
9.1 Reference to an internet source
http://www.google.co.in/
http://en.wikipedia.org/wiki/Forensic_facial_reconstruction
http://en.wikipedia.org/wiki/Forensic_identification
http://en.wikipedia.org/wiki/Forensic
http://www.forensicpage.com/new05.htm
http://www.assemblage.group.shef.ac.uk/1/evison.html
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