Forensic Pathology
“This is the place where death rejoices
to teach those who live.”
Introduction

A death that is unexpected or is thought to have
been caused by injury or trauma is always
investigated.
 Coroner
 Medical Examiner
Coroner vs. Medical Examiner

Coroner – a public official, appointed or elected,
who makes inquires into deaths and completes
death certificates.
Determines cause/manner of death
 Decides if foul play
 May or may not have medical training

Coroner vs. Medical Examiner

Medical Examiner – a physician, evaluates
medical history and physical exam of deceased
to determine cause and manner of death.
Must receive special training to become a forensic
pathologist
 Forensic Pathology – unnatural or suspicious disease
or injury
 In most large US cities, the medical examiner is
required to be a forensic pathologist.
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Forensic Pathologist
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Education and Training
Medical school – 4 years

Post – medical training
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3 to 5 year residency in general pathology
Additional year of training

In medical examiners office (forensic pathology)
American Board of Pathology Exam
 Training / Knowledge in other areas of Forensics
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In US 500 Forensic Pathologists
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About 25 of the 500 also have LAW DEGREES
Deaths Investigated
Two Main Categories

1. Persons who die suddenly when in apparent good
health, those who are unexpected to die, or those
who are without medical treatment for fatal
diseases.
Public Health Threat (bacterial meningitus)
 Death in public places (electrocution in public place)
 Maternal Death
 Death outside of medical facility

Deaths Investigated
2. Deaths caused by unnatural causes
Examples:
Acts of violence
 Drug related
 Trauma / Asphyxiation
 Weather
 Vehicular accident

Deaths Investigated

Special Categories:
Under 18
 Death of an individual under legally dependent care.
 Death in correctional facility
 On aircraft or ship

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MURDERS ARE THE SMALLEST
NUMBER OF DEATHS
INVESTIGATED!
Three facets of guilt:
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Motive
Means
Opportunity
Medical Examiner’s Duties:
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Review eyewitness statements
Examine crime scene
Autopsy
Photography
Report
Testimony
Duties and Responsibilities
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Establish the cause of death
Establish the time of death
Infer the type of weapon used
Determine the manner of death
Identify the deceased
Determine the effects of trauma or pre-existing
conditions.
Postmortem Lividity
(Livor Mortis)

The Settling of blood that causes the skin to
change color
30 Minutes:

Changes in skin color first appear
on fair-skinned persons
4 to 8 hours:

The blood in capillaries settles
PERMANENTLY
Between 1 and 8 hours:

(1) Blanching
Light-colored marks
made by finger pressure
(2)

Where a trained investigator will begin..
Why livor mortis is important
Has the body been
moved?
Rigor Mortis


The period of time that a body goes through a
state of Rigidity
Caused by lactic acid build-up in the body.
Rigor Mortis Progression

Shorter muscles – face, fingers, toes
 Neck

Then moves down and out the long muscles of the
legs and forearms
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Legs stiffen last
Rigor MortisTime-line
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1-4 hours: Jaw and neck rigid, rest of body limp
Up to 8 hours: everything down to the legs is
rigid
For 12 hours: everything remains rigid
24 hours: Jaw is limp, everything else is rigid
30-32 hours: everything but the legs are limp
36 hours: entire body is limp (no rigidity)
decomposition has begun
Circumstances affecting
Rigor Mortis

Starvation
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Extreme temperatures

Physical exertion

Effects of fire

or water (in the case of drowning)
Decomposition

Bacteria: Co2 is produced, abdominal swelling

Blood vessels:
discoloration of skin in upper abdomen
 marbling effect
 Red → darker red → purple → green
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Putracine – foul- smelling, nauseating odors
Algor Mortis
Either Liver temperature (LT)
or Rectal Temperature (RT)
 Drop of about
2 degrees
per hour
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Factors affecting temperature loss:
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Size (mass) of body
Body Temperature at death
Temperature of crime scene
The Autopsy Examination
“You've got to be the type of person who can emotionally
disconnect [from] it. I mean, if you went into a case looking at it
as, 'Geez, this is somebody's little girl or somebody's little boy,'
you'd never be able to do the case. You can't personalize it in any
way... When you walk in, you never forget that this is
somebody's loved one. You never forget that, but when you walk
in to do the job, you kinda put that information aside. You look
at them more as a puzzle, and your job is to sort out this puzzle.
I've got to find out what happened. Who, what, why, when,
where. I mean, that's what my job is, to sort out and get those
answers. And, do it in a respectful way.
A lot of people can't do this type of job. A lot of people
don't want to do this type of job. There are a lot of jobs I
wouldn't want to do either.”
Eric Kiesel
Atlanta's Fulton County Deputy Chief Medical Examiner
HISTORY OF AUTOPSY
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EGYPTIONS
1600 BCE
HIPPOCRATES
– 5TH + 4TH CENTURY BCE
AUTOPSIES TO DETERMINE THE CAUSE OF
DEATH:
The Autopsy Examination

Legality
Permission required – family can request an autopsy
be performed (usually free)
 Next of kin must sign autopsy permit.
 Religious considerations
 Mandatory when death is suspicious of foul play or
if public health concern (in most states)
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The Autopsy Examination
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Attending Personnel
Diener – autopsy assistant
 Prosector - pathologist
 Pathologist Assistant
 Precautions – protective
clothing

The Autopsy Examination
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The External Exam = done first when body is
examined.
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Looking for:
 Wounds
 Contusions (Bruises)
 Unusual marks on the body
 Overall impression of the body
Forensic Autopsy
An intensive search for information
To locate PHYSICAL EVIDENCE to determine the cause of death
The Autopsy Examination
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At this point, a general description of the body is made.
All identifying features are noted including:
Race
Sex
Hair color and length
Eye color
Approximate age
Any identifying features (scars,tattoos, etc.)
The Autopsy Examination

Opening the Body

Y-incision: incision made from left and right
shoulders to mid-chest and straight down to pubic
region.
No bleeding (usually) because there is no blood
pressure.
 If head is to be opened, an incision is made across
the head from one ear to the other.
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The Autopsy Examination
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Rib cage is cut at the cartilage that joins the ribs
to the breastbone with a scalpel, saw or knife to
enter the chest cavity. Soft tissue peeled back to
look for abnormalities.
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Chest plate (ribs and breastbone) are removed
and examined. Often fractured during CPR.
Skull is cut in front and back for
removal.
The Autopsy Examination

Removing and Examination of the Organs
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Each organ is removed, photographed and weighed.
Organs are usually dissected and slides prepared to look
for disease or irregularities.
THE HEART
Checked for TRAUMA
Pulmonary artery
The pulmonary arteries carry blood from the
heart to the lungs.
They are the only arteries (other than umbilical arteries in the
fetus) that carry deoxygenated blood.
Looking for a blood clot that has dislodged from a
vein traveling through the heart
To the pulmonary artery: SUDDEN DEATH
Blood samples are taken from the
AORTA
Blood-typing and Blood/Alcohol test
Larynx and Trachea
Food lodged in trachea
Checked for food bolus (choking)
Lungs
Drowning
Diatoms
lungs
stomach
Blood stream
Bone marrow
Heroin Use
Carbonate crystals
Used to mix heroin
Will be found in the lungs
Death in fires
If alive
During
Fire there
Will be
soot and ash
in the Trachea
Bronchi
And
Lungs
If CO2 levels in blood are greater than
2%
The victim was alive at the onset of the fire
Samples taken
 CO2 and
other
gases in lungs
 Microscopic
slides
Liver
Liver
A healthy liver:
Soft, pliable, vulnerable to blunt-force trauma
Cirrhotic Liver
Caused by hepatitus, malnutrition, drug & alcohol use
Jaundiced Liver
Kidneys – filter blood
The “Kidney Punch”
A World Boxing Association foul
Drug use
Drug addicts who have a cirrhotic liver
cannot metabolize proteins……
Toxins pass out of the liver and
Damage kidneys
Diseased Kidneys
Jaundiced kidneys
Polycystic liver
Stomach
Important in drug-overdose cases
Helps establish activities prior to death
POISONS
CYANIDE
-red color of organs
-almond-like odor
(only 50% of pop can detect the odor)
-KCN used for executions
Estimated time of death
If TIME OF MEAL and MENU are known
Intestines
Location of food can help
determine time of death
Pair swallows 850 g cocaine..
“Katriya Connor, 23, a chef from Waterloo in Liverpool,
became violently ill on a flight from Cancun in Mexico
to Birmingham on February 6, after scores of packets
of cocaine that she had swallowed burst in her stomach.
She died within hours on an airport runway in the
Azores, where the flight had been diverted, while
paramedics desperately tried to save her life. A 21-yearold man, apparently travelling with Ms Connor, also fell
into a coma on the flight and remains seriously ill on
the island.”
(from The Guardian)
Stomach of drug “mule”
Drug packets in rectum area
Bladder
URINE SAMPLE
Reproductive Organs
Inspected for
pregnancy
(Teenage suicide)
The Brain
Removal of Brain
A blood clot caused by a blow to the head
– can be fatal
Formaldehyde “fixes” the brain for better dissection
Autopsy
Conclusion

Samples are obtained of bodily fluids and sent to
toxicology for examination.
Blood
 Urine
 Bile
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Manner and Cause of Death
Mechanism – biochemical or physiological
abnormality produced by the cause of death
that is incompatible with life.
 Manner of Death – homicide, suicide, natural
causes, accidental or undetermined.
 Cause – disease or injury that initiated the
lethal chain of events that lead to death
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Manner of Death
homicide
 Suicide
 accidental – trauma occurring from acts
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NO REASONABLE person
would have felt have a high probability
of injury or death
natural cause
 undetermined
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Determination of Cause of Death
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One can die of a massive hemorrhage (the
mechanism of death) due to a gunshot wound
through the head (the cause of death) as a result
of being shot (homicide), shooting yourself
(suicide), dropping the gun and it discharging
(accidental), or not being able to tell how it
occurred (undetermined). All of which are
manners of death.
Causes of Death
Brain Damage:
Subdural hematoma
Brain Damage:
Subarachnoid
hematoma
Brain Damage:
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Intracerebral hematoma:
Suffocation
Positional Asphyxiation
Positional Asphyxiation
SADS
Choking
Drowning
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Vomitos amigos:
Drug/alcohol
Intoxication
Neck Injuries
Strangulation
accidental
suicide
homicide
Petechial hemorrhage
Ruptures in the tiny capillaries
Hyoid Bone
Hanging
Nature of rope and knots
Suicide by hanging
Male suicide
Female suicide
Jugular vein
On average, blood accounts for 8% of total body weight
5 to 6 liters of blood for males
4 to 5 liters of blood for females
A 40 percent blood loss results in death.
The loss of 1.5 L can
cause incapacitation.
Jugular vein
Stab Wounds:
Sharp Force Trauma
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Type of knife used (width, length, single or
double-edged)
Stabbing wounds
Slicing wounds
Blunt Force Trauma
Caused by being struck by a flat surface
Gunshot Wounds
International Gun Statistics
Classification of Traumatic Death

Four Categories:
Thermal
 Chemical
 Electrical
 Mechanical
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Asphyxiation – interference of oxygen to brain
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Can be caused by all mechanisms
Mechanical Trauma
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Blunt or Sharp
Penetrating or Non-penetrating
Mechanical Trauma occurs when the applied
physical force exceeds tensile strength of the
tissue, causing lacerations (blunt force) or
incised wounds (sharp)
Mechanical Trauma
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Sharp Force Trauma
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Most common cause of death = exsanguination
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Major arteries or the heart are damaged
Blunt Force Trauma
Cause contusions or lacerations
 Most common cause of death = significant damage
to brain or internal bleeding
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Mechanical Trauma
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Firearm Injury
Contact wound – blackening of skin around wound
(gas “burns” skin), small in size
 Distant wound – circular skin defect and rim of
abraded skin around the edges
 Exit wound is larger and more irregular than entry
wound.
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Chemical Trauma
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Death that results from drugs or poisons
Alcohol = most common drug that causes death
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Rarely kills directly, but contributes to about 50% of
traumatic deaths.
Other chemicals:
Drugs
 Carbon Monoxide
 Cyanide / Arsenic (poisons)
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Thermal Trauma
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Exposure to excessive heat or cold
Hypothermia – excessive cold
 Hyperthermia – excessive heat
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Causes death via a breakdown in the normal
mechanisms that maintain body temperature.
Thermal Burns – death usually occurs as a result
of complications (shock; mechanism = multiple
organ failure)
Cause of death in fires – inhalation of CO, not
burns
Electrical Trauma

Passage of electricity through a person
Low Voltage – heart experiences ventricular
fibrillation (quivering of the heart; beats faster than
the body can handle)
 High Voltage – forces heart into tetany, a
contraction that is broken when the circuit is broken.
Heart generally starts again with a normal rhythm
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Loss of limbs or electrical burns are possible within
seconds of shock.