Forensic Anthropology A Resource for Investigators H. Gill-King, Ph.D., D-ABFA CENTER FOR H LABORATORY OF FORENSIC ANTHROPOLOGY OR HUMAN IDENTIFICATION UNIVERSITY OF NORTH TEXAS LABORATORY OF MOLECULAR IDENTIFICATION
Center for Human Identification Providing a multidisciplinary approach to remains analysis and identification Laboratory for Molecular lar Identification University of North Texas Health Science Center Fort Worth Laboratory of Forensic Anthropology University of North Texas Denton Forensic Odontology
What is Forensic Anthropology? Analysis of skeletal remains, using techniques derived from physical anthropology and skeletal biology, within a medicolegal context Includes the application of archaeological techniques to search and recovery e efforts
Types of Case Involvement Individual identification and analysis Majority of cases for most forensic anthropologists Primarily from law enforcement agencies Involve both identification and analysis
Mass disasters Types of Case Involvement Political, accidental, natural Pi Primarily il an identification effort Atrocities / War crimes / Crimes against humanity Mass identifications Analysis differentiation from normal conflict trauma
Anthropological Services Location/Recovery of remains Exhumations Decomposed, scattered, burned, buried, submerged, fragmentary remains Examination of skeletal remains Skeletal identifications Submissions to the Missing Persons DNA Database Victimology Expert testimony
Anthropological Services, cont. Skeletal Remains Examinations Forensic significance Postmortem interval Biological profile: Sex, Ancestry, Age, Stature/physique Unique identifiers: skeletal features, pathology, medical history Antemortem and perimortem trauma
Forensic Odontology
Anthropological Information The forensic anthropologist s s primary mission is to provide information to the investigating agency!
Location and Recovery
Determination of Forensic Significance Is the case a matter of legal interest? In other words, Is this a case that investigative agencies need to pursue? Human vs. Non-human Contemporary vs. Historical or Archaeological
Human vs. Non-human Differences in gross anatomical structure Greatest differences found at articular ends Differences in microscopic structure Usually very quick, simple analysis E-mail submissions may save TIME
Non-Human and Children Potentially the most difficult distinction between animal and human Small mammals and infants can be easily confused Distinctive features of bone have not fully developed in children
Which are Human?
Forensic Significance Modern vs. Historical / Archaeological Things that are normally not forensically significant: Archaeological Remains Cemetery Remains Medical Specimens Trophy Remains
Modern Aesthetic Modification
Modern Medical Intervention Orthopedic appliances Replacement surgeries (hip, knee, etc.) Fracture stabilization Surgical procedures Dental restorations or appliances All of these may have antemortem records which could be used to make an identification!
Taphonomy and Postmortem Interval
Biological Profile Basic Identification Parameters 1. Sex 2. Ancestry 3. Age 4. Stature Information to narrow the search for possible missing individuals Data to filter potential DNA matches
Determination of Sex
Sex Determination Based on the premise that humans are somewhat sexually dimorphic Pelvis Cranium Areas of muscular attachment tend to be more robust in males males (although secular occupational trends may represent a change) Postcranial bone other than the pelvis Metric analysis (population must be known) Discrete non-metric traits (olecranon perforation, suprascapular notch, etc.) Potential evidence of childbirth
Ancestry (Race, Biotype)
Ancestry and Race Race is a term with a multitude of definitions iti and cultural l implications Long-term evolutionary characteristics associated with geographic regions and population groups we are not evaluating culture or where an individual was born Admixture and variation make ancestral assessments somewhat problematic Investigators need to know how others would view the individual
Evaluation of Ancestry Craniofacial characteristics vary between groups (esp. midface morphology) Discrete (genetically unique features) Non-metric traits (sutural patterns, hair, prognathism, etc.) Metric discriminant function analysis (biological distance) Postcranial a metric differences e and appendicular proportions Dental characteristics Genetic polymorphisms
Age Estimation
Age Estimation Skeletal age estimations must be given as a range Usually, the estimation range is more precise with younger individuals id Methods used to estimate age differ for different age ranges: Infants and children bone development and dental formation/eruption Adolescents dental completion and final bone development Adults age related changes to mature bone
Stature and Physique
Biological Profile & Variation The anthropologist is attempting to categorize the remains based on variation in the population and differences between groups Some classifications will be made with more certainty than others depending on where that individual is in the variation. When using a biological profile to search various databases: Individuals falling somewhat outside of the reported profile should not necessarily be excluded without further investigation if in doubt, call your anthropologist
Individualizing Features
Skeletal Analysis - Trauma Distinction between antemortem, perimortem, and postmortem t trauma Possible identification from antemortem trauma (given appropriate records) Possible determination of cause and/or manner of death Recognition and interpretation of sharp force, blunt force, and ballistic injuries Identify dismemberment or attempts to obscure identification
Reconstruction
Blunt Force Trauma Impact with a blunt object with sufficient force to damage bone Moving object Baseball bat, vehicle Moving individual id Falling body, thrown against an object Considerations: Mass, velocity, shape of object
Blunt Force Findings Number of impacts Sequence of impacts Evidence transfer Time (ante-, peri-, postmortem) Type(s) and number of weapons Occasional individualization of weapon Confusion with atypical GSW Energy delivered (may exclude suspect)
Defensive Fracture
Intracranial Trauma
Healed Blunt Force Trauma Healed radiating fracture Impact site
Ballistic Trauma Blunt object impacting bone over a small area with high velocity, creating a unique set of characteristics Factors affecting the defect: Caliber Projectile construction Velocity Stability of projectile Contact injuries expansive gasses
Potential Ballistic Findings Presence of ballistic injuries in bone Gross observation: classic entry/exit X-rays / SEM / EDX Number of shots Order of shots Class of weapon Projectile path / angle through the body Approximate caliber (exclusions) Position of barrel Hard / soft ammunition
Typical Ballistic Injuries
Reconstruction of Wound Track
The wound track describes the relationship between the projectile and the victim. It does NOT place the victim or assailant at a particular location within the crime scene.
Antemortem Ballistic Injuries
Atypical Ballistic Injuries Oval aperture low angle or tumbling round Keyhole defects Very low angle of incidence Beveling internally and externally Round may not enter the cranial vault! Irregular defects - Unstable projectiles Intermediate targets: brush, glass, other tissue, etc. Shored exits
Entry exits right temporal Exit from right parietal injury
Atypical Intermediate Target
Atypical Locations n o i t y a c g i f o i l t o n p e o d r I h t n n a A m c u i s H n r e o r f o r F e t f n o e C ory t T a N r U bo a L
Stab Sharp Force Trauma Typically greater in depth than length Produced by a thrusting action (force roughly perpendicular to the surface) Incised (cut) Typically greater in length than depth Produced by a slashing action (movement along the surface)
Chop Sharp Force Trauma Somewhat sharp cutting object that is heavy (axe) and/or moving at high velocity y( (mower blade) Potential characteristics of both sharp and dbl blunt tf force trauma
Sharp Force Findings Length / width issues Backed vs. double-edgeedge Class characteristics Associated garments Anatomical learning Toolmark transfer (possible individualization) id Confusion with scissoid mouth parts (ie animal vs. instrument) t)
Common Sites Ribs and Vertebrae Vital organs Hands Lateral aspect and flexor surface Defensive posture / grasping blade Joint surfaces / margins Typical of dismemberment
Sharp Force - Stab
Sharp Force - Incised
Sharp Force - Chop
Sharp Force - Chop
Sharp Force Toolmarks
Thermal Effects Burned green or dry Temperature /ti time estimates t (address accelerant issues) Heat effects in prosthetic ti materials (dental, orthopedic, other) Flash and barotrauma vs. position Red flag observations supine / prone Cranial blowout vs. thermal loading
Thermal Effects, cont. Obscured perimortem injury Animal vs. human Shrinkage distortion vs. biological profile Who burns fastest? Can a body be burned up? DNA extraction issues Special handling and lab protocol apply (significant damage to evidence possible at several steps)
Multiple Classes of Trauma Blunt and Sharp Force
Multiple Trauma Classes Blunt Force Impact Ballistic Entry Sites
Dismemberment Usually blade and/or saw Progression of learning in blade disarticulations Fewer trial marks in later attempts More precise Use of multiple instruments Characterization of saw cuts Type of saw Kerf, blade characterization ti Direction of cut
Cut ulnar head with vital reaction Bladed Disarticulation of Hand
Decapitation with Trial Cuts
Hand Saw Dismemberment
Saw Cut Interpretation Direction of cut Kerf width and divergent tooth th profile Fracture spike
Direction of Cut
Attempt to Obscure Identity Avulsion of Teeth Note: intact roots
The would like to acknowledge the following National Institute of Justice UNTHSC Office of Professional and Continuing Education