UNT Center for Human Identification. Laboratory of Forensic Anthropology. For information or assistance, please call (800)

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1 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

2 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

3 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

4 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

5 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

6 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

7 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

8 Forensic Odontology

9 Anthropological Information The forensic anthropologist s s primary mission is to provide information to the investigating agency!

10 Location and Recovery

11 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

12 Human vs. Non-human Differences in gross anatomical structure Greatest differences found at articular ends Differences in microscopic structure Usually very quick, simple analysis submissions may save TIME

13 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

14 Which are Human?

15 Forensic Significance Modern vs. Historical / Archaeological Things that are normally not forensically significant: Archaeological Remains Cemetery Remains Medical Specimens Trophy Remains

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18 Modern Aesthetic Modification

19 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!

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21 Taphonomy and Postmortem Interval

22 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

23 Determination of Sex

24 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

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26 Ancestry (Race, Biotype)

27 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

28 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

29 Age Estimation

30 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

31 Stature and Physique

32 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

33 Individualizing Features

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37 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

38 Reconstruction

39 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

40 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)

41 Defensive Fracture

42 Intracranial Trauma

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47 Healed Blunt Force Trauma Healed radiating fracture Impact site

48 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

49 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

50 Typical Ballistic Injuries

51 Reconstruction of Wound Track

52 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.

53 Antemortem Ballistic Injuries

54 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

55 Entry exits right temporal Exit from right parietal injury

56 Atypical Intermediate Target

57 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

58 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)

59 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

60 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)

61 Common Sites Ribs and Vertebrae Vital organs Hands Lateral aspect and flexor surface Defensive posture / grasping blade Joint surfaces / margins Typical of dismemberment

62 Sharp Force - Stab

63 Sharp Force - Incised

64 Sharp Force - Chop

65 Sharp Force - Chop

66 Sharp Force Toolmarks

67 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

68 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)

69 Multiple Classes of Trauma Blunt and Sharp Force

70 Multiple Trauma Classes Blunt Force Impact Ballistic Entry Sites

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72 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

73 Cut ulnar head with vital reaction Bladed Disarticulation of Hand

74 Decapitation with Trial Cuts

75 Hand Saw Dismemberment

76 Saw Cut Interpretation Direction of cut Kerf width and divergent tooth th profile Fracture spike

77 Direction of Cut

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80 Attempt to Obscure Identity Avulsion of Teeth Note: intact roots

81 The would like to acknowledge the following National Institute of Justice UNTHSC Office of Professional and Continuing Education