Determination of the Interval Since Death

• Body Temperature

• Livor Mortis

• Rigor Mortis

• Decomposition

• Insect Activity

Body Temperature

• “Algor Mortis” – Body loses heat after death

• Core temp falls by ~1.5 ° F / hour

• Problems:

– “Normal” body temperature varies

– Environmental temp variation

– Also:

• Body size

• Clothing

• Air movement

Livor Mortis

• Blood clots in areas free of pressure

• Bruise-like coloring

• Areas with pressure prevents pooling

• “Fixed” after 4-6 hours

– Position of body at death

Livor Mortis

Rigor Mortis

• Stiffening of the body after death

• Muscle cells still function w/o oxygen à anaerobic function

• Appears 2-4 hours after death, entire body by 6-12 hours

• Persists for 24-48 hours

• Lost due to decomposition

• Variation

Decomposition

• Processes

– Autolysis: Breakdown of tissues by chemical process after cell death

– Putrefaction: Breakdown of tissue due to bacteria (mainly from GI tract)

• Also:

– Scavengers

• Insects

• Carnivores

Stages of Decomposition

• Fresh

• Early Decomposition

• Advanced Decomposition

• Skeletonization

• Extreme Decomposition

• Fresh:

– Fresh appearance

– No discoloration of skin

– Little or no insect activity

• Early Decomposition

– Discoloration

– Putrefaction

– Bloating

– Skin slippage

– Marbling

– Purge fluid

Bloating & Discoloration

• Advanced Decomposition:

– Loss of internal organs

– Lots of maggots

– Flesh sagging

– Adipocere

– Less than 50% of skeleton exposed

• Skeletonization:

– More than 50% of skeleton exposed

– Greasy or dry bones

– Dessicated soft tissue

– Some body fluids may be present

• Extreme decomposition:

– Skeletonization with bleaching

– Exfoliation

– Trabecular bone exposed

Decomposition

• Sequence predictable but duration varies

• Factors:

– Embalming

– Environmental temperature

– Humidity

– Burial vs. surface

– Access by scavengers

Variation in Rate

• Skeletonization in days, months, or years

– Hot, Arid Climates (Arizona)

• Skeletonization: 3 mos. – 3+ years

– Warm, Moist Climates (Tennessee)

• Skeletonization: 1 month – 1 year

Forensic Entomology

• Study of insects as related to medicolegal investigation of death

– PMI

– Season

– Movement of body after death

– Trauma

• PMI

– Blowflies & beetles

– Ratio

– Life Stage

• Region Specific

Blowfly Life Cycle

Dermestid Beetles

Positive Identification

Types

• Dental Radiograph

• Medical Radiograph

• DNA

• Pathologies*

• Skull-Photo Superimposition (not positive ID)

– Exclusion or support

• Facial approximation (not positive ID)

– Target Search

• Dental Identification

– Must have lead on victim’s identity

– Dental records NOT sufficient to establish positive ID

• Can substantiate probable ID

– Positive ID established using radiographs

• Try for maximum number of points of similarity

– At least 12, preferably 15-16 for positive ID

Postmortem vs. Antemortem x-rays

-comparison of points:

-restorations

-roots

-pulp chambers

-trabeculae

• Unique dental appliances

• Medical Radiographs

– Medical interventions

– Morphology of bones

– Trabecular patterns

– Cranial radiographs

• Frontal sinus

Frontal Sinus Patterns

• Air pocket in frontal bone

• Distinctive, even between twins

PM x-ray of unknown individual vs. AM x-ray

Orthopedic Screws

Testing

• Radiographic IDs 100% accurate when done properly

• Stability over time

– AM/PM comparisons over 10-27 yr. span on chest x-rays

• Still match morphology

• Biggest issue is trying to replicate position

DNA

• DNA Types:

– Nuclear (DNA or nDNA)

– Mitochondrial DNA (mtDNA)

• DNA—non-skeletal cases

– DNA or mtDNA from body fluids, hair, skin, etc.

• DNA—skeletal cases

– Typically mtDNA

Pathologies

• Sometimes a positive ID without antemortem x-ray

• Radiographic records may not exist

• Based on someone’s report of symptoms and match with biological profile

Skull-Photo Superimposition

• Concern over magnification and distortion

• Best means of getting a match is dentition

– Person must be smiling in photo

– Teeth must be retained PM

• NOT positive ID (See Case Report 8/13/99) but can exclude

Note orbits and skull outline

• Some tests of accuracy

Facial Approximation

• Facial “Reconstruction”

• Methods:

– Sketch

– “Rebuilding” Face

– Computer-Assisted Techniques

Sketches

• Sketch artist interpretation

– Biological profile

– Unique traits

– Facial shape

– Hair (if known)

• Problems

– Soft tissue

– Hair

Facial Rebuilding

– Tissue thickness depths at various points

-Information available for sexes and different ancestries

Facial Rebuilding

Facial Rebuilding: The Finished Product!

Another Reproduction—Kennewick Man

Jean-Luc?

Computer-Aided Techniques

• Tissue thickness data

• Scanned into computer

• Features chosen from options

• Not positive ID

• Similar problems as rebuilding

Human Rights & Forensic Anthropology

Human Rights

• Doctrine that invokes a realm of justice and morality beyond and superior to particular countries, cultures, and religions

• Vested in individuals

• 1948 Universal Declaration of Human Rights (UN)

• Application of techniques of forensic anthropology to human rights work

– Main differences: Scale, Perpetrators of crimes, and ID procedures

• Physical evidence to corroborate verbal testimony

• Partnership begins in 1984 with AAAS conference; Clyde Snow & Eric Stover

• Greatly expanded use around world

– “Local” forensic teams

– United Nations sponsorship (ICTR; ICTY)

• Physicians for Human Rights (PHR)

– Forensic Investigations

– Monitoring

– Training

• Recent Investigations in:

– Yugoslavia (UN; PHR)

– Rwanda (UN; PHR)

– Afghanistan (PHR)

– Iraq (PHR)

Srebrenica, BiH

• Fell to Serbs after siege from July 6-11, 1995

• 23,000 women and children removed to Tuzla and Kladanj

• Adult men made to stand trial for war crimes; thousands executed

• July 11—~15,000 men escaped and fled Srebrenica

Srebrenica Excavations -- 1996

• Cerska

– Over 150 bodies recovered (males; GSWs)

• Nova Kasaba

– 33 bodies recovered (many blindfolded & bound)

• Lazete & Pilica Farm

– 200 bodies recovered (multiple GSWs)

• All bodies transported to Tuzla for autopsy

Vukovar, Croatia

• Vukovar (pop. 85,000) sieged for three months; culminated in Serb takeover (November 1991)

• About 5000 people killed

• Virtually 100% of buildings sustained heavy damage

• Vukovar hospital taken over—300 men removed from the hospital

Vukovar (Ovcara) Mass Grave

• Discovery of mass grave in Ovcara in 1992

• 200 bodies recovered during 1996

• Scene processed for evidence including bullets, casings, etc.

• Bodies transported to Zagreb, Croatia for autopsy

• 91 of 200 individuals positively identified

Identification Project

• Bodies examined with two main goals:

– Identification

– Trauma and cause of death

• Antemortem database:

– Family and friends of missing asked a series of 275 questions

– Medical and dental records

– DNA (mtDNA & nDNA) analysis

Vukovar (Ovcara) Case

• Indicted in Ovcara case:

– Mile Mrkšic

– Veselin Šljivancanin

– Miroslav Radic

– Slavco Dokmanovic

– Slobodan Milosevic

• Case IT-95-13a (Dokmanovic)—Trial 1997-1998

• Case IT-02-54 (Milosevic)—Trial 2002-present

• Mrksic, Sljivancanin, and Radic all in UN custody awaiting trial