Forensics Part 1 Flashcards
Define Cause of death
condition, disease, injury that caused the mechanism of death
Define Mechanism of death
final pathophysiological event that results in death
Accurate death certification schema
Mechanism of Death due to Cause of Death = manner of death
What elements may encompass an opinion on the manner of death besides the autopsy?
scene where body was found/where person had died
Manners of death
Natural, accident, suicide, homicide, undetermined
Murder vs. homicide
homicide is the killing of one person by another (ex. MVC), while murder is the intentional, criminal killing of one person by another
Why does an accurate death certificate serve the public interest?
Medical Examiners do not work for families, but work for the public in order to determine the probability of foul play or some other crime–potentially something that may be solved or avoided in the future.
Rigor mortis
body/muscles are stiff, peaks at 24 hours
Algor mortis
cooling of body, takes a longer amount of time to establish than rigor mortis
Livor mortis
blood becomes fixed or pooled
Putrefactive decomposition
endogenous bacteria go throughout the body in order to reduce it to liquid/gas; occurs in temperate climates
Adipocere formation decomposition
occurs when a body is fully immersed in water, saponification of the skin
Mummification decomposition
occurs in dry, hot environments; body becomes wrinkled and is often well preserved
Status and training of medical examiners
Licensed physician and pathologist
Ability to determine time of death by a ME
not a very accurate way to determine this and is most often not exactly correct or precise
Coroner
elected position that does not require medical expertise, may be able to sign death certificate
Justice of Peace
elected or chosen, may be able to sign death certificates
Major misconceptions of forensics
Time of death cannot always be determined, testing takes a while and is not instantaneous, legal data bases are not a real thing
Role of medical examiner
assign a cause of death and a manner of death
Hospital autopsies are usually done to determine…
natural causes of death
Why are autopsy rates so low?
prevent legal cases and issues
What type of death certificate may physicians legally sign?
natural
What type of death certificates may MEs legally sign?
natural, accident, homicide, suicide, undetermined
Function of criminology in medicolegal investigation
responsible for profiling, fingerprints, voiceprints, facial recognition, handwriting analysis, etc.
Function of entomologist in medicolegal investigation
look at types of insects in body to locate wound sites, among other things
Ionizing radiation use and long term effects
Diagnostic, therapeutic uses but can cause fibrosis, mutagenesis, carcinogenesis, and teratogenesis
Most susceptible systems to radiation injury
hematopoietic and lymphoid systems
Sites of Radiation Injury
1-2 Sv lymphocytes, 2-10 Sv Bone Marrow, 10-20 Sv small bowel, >50 Sv brain
Types of wounds produced by blunt force
abrasion, contusion, laceration
Wounding formula
W= E x 1/T x 1/A x K
Definition of contusion
bruise that results from hemorrhage into soft tissue due to rupture of subcutaneous blood vessels by blunt force injury
Extent and severity of a contusion depends on what factors?
amount of force, vascularity of tissue, type of tissue, location of tissue, easy bruisability
Most significant bruise color
Yellow, presence indicates that bruise is 18 hours or holder
Definition of abrasion
wound in which epidermis is injured, produced by scraping away epidermis or crushing of the epidermis by direct pressure or tangential blow, oozes serum or blood
Types of abrasions
brush, patterned, impact
Laceration
splitting or separation of the skin, not from incise, but blunt force
Comorbid factors that may exacerbate wounding
coagulopathies, bleeding disorders, age, liver disease
Stab wound
sharp force injury in which depth of wound is greater than length
Energy formula/wounding potential of guns
KE = (1/2)m x V^2
Velocity is significantly more important
Contact/close range wound
marginal abrasion; soot or power in wound
Intermediate range wound
marginal abrasion, powder tattooing/stippling around wound
Distant range wound
marginal abrasion, no powder tattooing/stippling, no soot/powder in depths of wound
Skull entry wounds
sharply circumscribed and inner table is beveled
Skull Exit wound GSW
not circumscribed, outer table beveled
Can skull fractures be more accurately time stamped?
Yes, fractures from a blunt force or GSW do not ramify across previous fracture lines,
Low velocity wounds
small entry, no exit
High velocity wounds
relatively small entry, big exit
Macro level surveillance of crime scene includes…
safeguarding, surveying, documenting, proper approach to specimen retrieval
Micro level surveillance of crime scene includes…
biologic materials retrieval and transmittal vs. inorganic specimens/substances
Organization of crime scene by ME
alphanumeric gridding
