1. Death Investigation
SFS2 Students will use various scientific techniques to analyze physical and trace evidence. c. Evaluate how post mortem changes are used to determine probable time of death SFS5 Students will evaluate the role of Forensics as it pertains to Medicolegal Death Investigation a. Identify the various causes of death b. Analyze evidence that pertains to the manner of death c. Interpret various modes of death.
Forensic Science II: Autopsy, Chapter 8
© 2012 Cengage Learning. All Rights Reserved

2. Madison Rutherford In 1998, Rutherford drove his car off the road.
The car caught fire and Rutherford died.
A $7 million life insurance policy would go to his wife, but only after an investigation.
An autopsy revealed:
the skull fragments were in an unlikely position
the bones indicated arthritis
the dentures records didn’t match
Rutherford faked his death.
Forensic Science II: Autopsy, Chapter 8
© 2012 Cengage Learning. All Rights Reserved

3. History Forensic Science II: Forensic Entomology, Chapter 12
© 2012 Cengage Learning. All Rights Reserved

4. Introduction
By law, deaths occurring under these circumstances must be investigated:
Violent crime, suicide, or accident
Within 24 hours of entering a hospital or having surgery
A natural death when a doctor is not present or the patient is not under the care of a medical facility
Occurs in police custody or in a correctional facility
Results from a communicable disease that may pose a threat to public health.
Forensic Science II: Autopsy, Chapter 8
© 2012 Cengage Learning. All Rights Reserved

5. Historical Events Two systems of death investigation exist in the US
The coroner system dates to 12C England; sometimes the position:
is an elected official
requires a medical doctor
requires a forensic pathologist.
The medical examiner system dates back to 1870
an experienced physician with
advanced training in pathology
Forensic Science II: Autopsy, Chapter 8
© 2012 Cengage Learning. All Rights Reserved

6. Death The Manner of Death
The manner of death can be natural, accidental, suicidal, homicidal, or undetermined.
Sometimes it is difficult to determine the manner of death.
The most common manner of death is natural.

7. Cause and Mechanism of Death
Cause of Death
Describes events leading to death
Examples: stroke, drowning, shooting, etc.
Mechanism of Death
Specific change in body that brought about death
Examples: loss of blood, pulmonary arrest, etc.
Forensic Science: Fundamentals & Investigations, Chapter 11

8. Time of Death: Livor Mortis
Lividity The Color of Death
When red blood cells break down, they turn a bluish-purple.
With decomposition, blood seeps down and settles in the lower parts of a body.
The discoloration that accompanies this becomes permanent after about 10 hours.
Warmth accelerates the process.

9. Time of Death: Rigor Mortis
The Rigidity of Death
At death, skeletal muscles cannot relax.
Without oxygen, calcium accumulates in these muscles.
The muscles become stiff.
This starts in the head and works its way down to the legs.
After about 12 hours, the muscle fibers begin to slowly dissolve, and softening begins.

10. Time of Death: Rigor Mortis
Many factors affect when rigor mortis sets in and how long it lasts:
Ambient temperature
The weight of the body
The body’s clothing or lack of it
Any illness the person had at the time of death
The level of physical activity at the time of death
Sun exposure

11. Approximate times for rigor mortis in temperate regions (just a reference/estimate)
Body temp. Body stiffness Time since death
warm not stiff dead not more than 3 hrs
warm stiff dead 3 to 8 hours
cold stiff dead 8 to 36 hours
cold not stiff dead more than 36 hours

12. Time of Death: Algor Mortis
In death, a body no longer generates warmth and begins to cool down.
To find the standard temperature of a corpse, a thermometer is inserted into the liver (sometimes it will be done rectally).
Body heat is lost at about 1 to 1.5 °F an hour.
Time of death determined by temperature calculations is expressed as a range of time.

13. Effects that Influence Algor Mortis
Temperature of the surrounding environment
Type of clothing on the body
Wetness of the clothing
Air movement
Layers of clothing
Size of the individual
Forensic Science: Fundamentals & Investigations, Chapter 11