Q7: DEATH

FORENSIC PATHOLOGY Def: Branch of Forensics concerned with determining the cause of death by the examination of a cadaver Cadaver Formal term for Dead body Medical training and research Coroner or Medical Examiner

DEATH In the U.S. a person is considered dead by law if a Statement of Death (Death Certificate) is approved by a licensed medical practitioner “Possession of brain activity, or capability to resume brain activity, is a necessary condition to legal personhood.”

DEATH Def: The termination of all biological functions that sustain a living organism. Phenomena which can bring about death include: Senescence (Biological aging) Malnutrition Disease Suicide Homicide Starvation Dehydration Accidents/Trauma

SENESCENCE Most animals who survive external hazards will eventually die from “biological aging”. Some animals experience Negligible Senescence or even experience Biological Immortality

NEGLIGIBLE SENESCENCE Lack of symptoms of aging No detected increase in mortality rate after maturity Equally likely to die at any age after maturity No measurable reductions in reproductive capabilities

BIOLOGICAL IMMORTALITY Stable or decreasing rate of mortality with chronological aging Tardigrades

DEATH The key to Death is STOPPAGE Once the Heart stops beating… Cells will not receive oxygen. As oxygen levels dropping leads too failure of… Nerves Muscles Organs Brain Once a cell dies it breaks down. Once enough cells begin to break down life cannot be restarted

AUTOLYSIS Autolysis: Cell breakdown Cell membrane dissolves Enzymes and cell contents spill out into the body Enzymes and cell content digest tissue

ROLE OF THE PATHOLOGIST Primary role is to determine the Manner of Death. Does this by determining… Who is the victim? When did the injuries occur? Why did the injuries occur?

MANNERS OF DEATH Officials responsible for investigating death determining the manner of death 5 Manners of Death 1.Homicide Death of one person caused by another 2.Suicide Purposely killing oneself 3.Accidental Unplanned event 4.Natural Failure of body due to old age/disease Most common manner 5.Undetermined

MANNER VS. CAUSE VS. MECHANISM OF DEATH Manner: the WAY a person can die Cause: the REASON someone dies Mechanism: the specific CHANGE IN THE BODY. Example: Two men have an altercation outside a Las Vegas night club. One man pulls out a gun and shots the other man in the head. He dies What is the Manner of Death? Homicide What is the Cause of Death? Bullet to the head What is Mechanism of Death? Loss of Blood or Cessation of Brain Function

STAGES OF DECOMPOSITION (5) Help to give an estimation of when Time of Death occurred 1.Fresh Pallor Mortis Algor Mortis Rigor Mortis Livor Mortis 2.Active Decomposition 3.Bloated 4.Advanced Decomposition 5.Dry/Skeletal

PALLOR MORTIS Post-mortem paleness that occurs within minutes of death Happens so quickly that it has little to no use in determining time of death

ALGOR MORTIS Def: Reduction of body temperature following death Thermometer is inserted into the Liver After death  cooling rate is 1.4°F per hour After 12 hours  0.7°F per hour (until ambient temp is reached) Influenced by 1.Location of body 2.Position of body 3.Size 4.Clothing –Clothed body of average build loses about 3.5 degrees F in about 6-8 hours 5.Decomposition/maggots 6.Cause of death –Hypothermia –Sepsis (infection/inflammatory )

RIGOR MORTIS Definition: The relaxation and stiffening of muscles immediately following death Starts 2 hours after death Starts at head and works its way down to the legs Stiffening rates Face  2-4 hours Limbs  4-6 hours Entire body  12 hours Stiffness gradually disappears after hours

LIVOR MORTIS Def: The settling of blood in the body parts closest to the ground following death due to the heart no longer pumping Purplish blue  1-3 hours Purplish red  4-6 hours Also helps to determine if a body has been moved

PRE-CUT STEPS OF AN AUTOPSY 1.Documenting Tape recorders, photos, notes, etc Detailed description of the body Height, Weight, etc Birthmarks, scars, and tattoos Underneath fingernails Droplets of blood Unusual fibers Organic material and residues

PRE-CUT AUTOPSY STEPS CONTINUED… 2. Dental Work and X-rays Broken or fractured bones Injury history Medical devices Pace Maker 3. Blood Sample

PRE-CUT AUTOPSY STEPS CONTINUED… 4. Swab orifices (openings)  Mouth  RectumTed Bundy bite victim  Sexual organs  Bite marks 5. Genital area Rape Bruising Tearing

PRE-CUT AUTOPSY STEPS CONTINUED… 6. Hair is combed (including pubic hair) 7. Looking for signs of asphyxiation  Asphyxiation = severe depletion of oxygen to the brain  Signs Formation of Petechia  Small dots  Ruptured blood vessels Cyanosis Bluish color of skinJonBenet Ramsey

AUTOPSY STEPS Cutting the body “Y” incision from each shoulder Straight line cut down the chest to belly button Check rib cage Tupac Shakur

AUTOPSY STEPS Split rib cage Check vital organs Weigh Tissues samples sent to lab Second blood sample directly from heart Check stomach Partially digested food can be used as evidence Repeat process for lower body