Exam 2 Flashcards
what is blood pattern evidence used for?
- corroborate statements
- apprehend suspects
- interrogate suspects
- reconstruction of scene
strengths/weaknesses of blood pattern evidence
only as valid as information available/examiners abilities
history of bloodstain analysis
1895 - Piotrowski 1939 - Balthazard 1955 - Kirk 1971 - MacDonell 2002 - SWGSTAIN
healthy adults contain how much blood?
4.5-6.0 liters
spattered blood
distribution of bloodstains created when enough force is exerted to overcome surface tension of blood
factors that help to determining mechanism
- quantity
- force
- texture
impact spatter patterns (gunshot)
- mist-like
- 1 to 3 mm
satellite spatter patterns
smaller drops of blood that have detached from the initial blood drop
-0.1 to 2.0 mm
castoff bloodstain patterns
created by subsequent blows to the same area where a wound has occurred and blood has accumulated
expirated bloodstain patterns
expelled blood from the nose/mouth
- vacuoles=air bubbles
- diluted from spit/snot
transfer bloodstain patterns
when a object we with blood contacts a secondary surface
skeletonized
center of a dried bloodstain flakes away and leaves a visible outer rim
clotting
happens when blood is exposed to a foreign surface
void areas
absences of bloodstains
documentation of bloodstains
- more than one medium
- measure w/in photos
- size, shape, distribution & pattern
IABPA
established in 1983 w/ 800 members
existence of death investigation
- England - before 10th century
- U.S. - 1990’s
1877: Massachusetts
replaced coroner with licensed medical examiner
forensic pathology
studies diseases, its causes, and its diagnosis
specialized areas of forensic pathology
- anatomic: autopsies/examine tissues
- clinical: manage bodily fluids in labs
WWII
- MEs required to be forensic pathologists
- coroners have forensic pathologists do autopsies
purpose of death investigation
- determine cause/manner
- help draw conclusions
- supports conclusions
“injury trumps disease”
WRONG
manner of death
fashion in which the cause of death came to be
-NASH
order of time of death
rigor, livor, algor
rigor mortis
stiffening of muscles
-chem reaction of glycogen
livor mortis
discoloration of the body
-settling of red blood cells
algor mortis
cooling of the body
determining jurisdiction
two-pronged test
- sudden death
- unexpected
reviewing witness statements
- helps determine jurisdiction
- questions to be answered
- refutes statements
- predicts judgment
questions answered by scene examination
- post-injury movement
- time b/w injury/death
- time of injury/death
- time of unconsciousness
autopsy process
- remove organs (inframammary incision)
- examine brain
- weigh/dissect organs
- police custody
toxicologists
test:
-blood, urine, bile, portions of internal organs
investigation of traumatic death
- NASH
- mechanical
- thermal
- chemical
- electrical
penetrating
bullet in, doesn’t come out
perforating
bullet in and out
most common drug seen in forensic practice?
ethanol (alcohol)
alcohol
- 0.25: coma
- 0.30: deep coma/slow breathing
cocaine at high doses
seizures, high body temp, quivering of the heart
CO poisoning
- death by asphyxiation
- cherry color under skin
cyanide poisoning
- almond odor
- CA: death penalty
hyperthermia
excessive heat
hypothermia
excessive cold
thermal trauma
-few demonstrable signs found at autopsy
electrical trauma
- low voltage: ventricular fibrillation
- high voltage: tetany (burn)
asphyxias (drowning)
-conscious: excitation phase
hemorrhage
water in sinuses/brain
hyperinflation
asphyxias (strangulation)
- manual: hands/arms
- ligature: anything around neck
*hyoid bone, cornu, hemorrhage
forensic anthropology
application of the theory/methods of anthropology to forensic problems
tasks of forensic anthropology
- i.d. victim
- taphonomic assessment
- provide data regarding death events
involves multidisciplinary team
forensic anthropological profession
1939: Krogman
1972: AAFS established
1977: ABFA established
number of bones in adult/infant body
adult - 206
infant - 405
benefit of outdoor screens (when recovering remains)
- improve recovery success
- map a scatter plan
- document rship b/w body parts/other evidence
process of recovering remains
- make grid
- pics/document before work
- examine for bugs/plants
- remove remains gradually/record position
taphonomic context
immediate environment and surroundings where the body is found
taphonomic context aids in
- interpretation of condition of remains
- estimating postmortem interval
- location of death
taphonomic assessment
documentation of the condition of the body
- stage of decomp
- amount of scattering
- drying/bleaching by weather
- other changes
goal of a biological profile
describe the individual as to narrow the range of possible identities
amount of teeth for child/adult
child: 20
adult: 32
most reliable indicator of age
*pubic symphysis
- 4th rib
- cranium
goal in estimating population ancestry
reduce the possibilities for group membership (age, sex or population)
allometry
the relation between the size of an organism and the size of any of its parts
aid of descriptive characteristics
- medical conditions
- handedness
- occupational stress markers
- congenital anomaly
- antemortem medical conditions/pathology
levels of certainty
- consistency
- probable
- beyond a reasonable doubt
abbreviated report
- chain of custody
- taphonomic assessment
- biological profile
- i.d. characteristics
- description of trauma
