1. Death Investigation

2. Summary Cause and Mechanism of Death
Mechanical trauma (gunshot, stabbing)
Chemical trauma (overdose, poison)
Other

3. K-Fed sez:
Quiz on Friday.

4. Death Investigation
Cause of death: disease or injury that initiated the events that led to death
Mechanism of death: Physical abnormality produced by cause of death that is incompatible with life.

5. Examples: Death Investigation
Richard Moll has purloined Marsha Warfield’s sack lunch from the set of Night Court 2010.

6. Examples: Mechanism of death: asphyxia Cause of death: smothering
Death Investigation
Examples:
Richard Moll has purloined Marsha Warfield’s sack lunch from the set of Night Court Marsha smothers him with a pillow. Richard Moll dies.
Mechanism of death: asphyxia
Cause of death: smothering

7. Examples: Mechanism of death: loss of blood Cause of death: stabbing
Death Investigation
Examples:
William Blake has set Siegfried and Roy’s tiger on fire. Siegfried stabs him in the aorta. The ambulance gets into an accident on the way to the hospital. Blake dies.
Mechanism of death: loss of blood
Cause of death: stabbing

8. Examples: Mechanism of death: heart failure Cause of death: gun shot
Death Investigation
Examples:
Man shot during robbery. Man stabilizes. Develops pnemonia. Followed by kidney failure, liver failure, heart failure, death. Had prior lung and heart disease, and probably would have survived if not for these diseases.
Mechanism of death: heart failure
Cause of death: gun shot

9. Determining the manner of death:
Death Investigation
Determining the manner of death:
Natural
Accidental
Homicidal
Suicidal
For example, a gunshot could be three of the above choices.
Manner may be undetermined.

10. Classification of Traumatic Deaths:
Death Investigation
Classification of Traumatic Deaths:
Mechanical
Thermal
Chemical
Electrical

11. Mechanical Sharp force (knife)
Death Investigation > Traumatic Death
Mechanical
Sharp force (knife)
Blunt force (gunshot, baseball bat, etc.)

12. Mechanical (sharp force vs. blunt force)
Death Investigation > Traumatic Death
Mechanical (sharp force vs. blunt force)
Sharp force
Sharp edges
Incised wound
Blunt force
Rough edges
Laceration

13. Mechanism of death usually loss of blood
Death Investigation > Traumatic Death
Mechanical (sharp force)
Difficult to determine size of blade from size of wound
Smaller/larger blade may cause larger/smaller wound
Mechanism of death usually loss of blood

14. Mechanical (blunt force - firearms)
Death Investigation > Traumatic Death
Mechanical (blunt force - firearms)
Most common homicidal & suicidal wound in US
Damage due more to velocity than mass
Wounds can be:
Penetrating: entrance wound, no exit wound
Perforating: entrance and exit wound

15. Mechanical (blunt force - firearms)
Death Investigation > Traumatic Death
Mechanical (blunt force - firearms)
Escaping gases may affect appearance of wound

16. Contact or near-contact wound
Death Investigation > Traumatic Death > Mechanical > Firearm Wound
Contact or near-contact wound
Gases burn (blacken) skin
Gases into wound tears skin (blown out appearance)
Possible head explosion

17. Intermediate range wound
Death Investigation > Traumatic Death > Mechanical > Firearm Wound
Intermediate range wound
Unburned powder creates stippling around wound.

18. Distance gunshot wound
Death Investigation > Traumatic Death > Mechanical > Firearm Wound
Distance gunshot wound
Circular hole with rim of abraded skin.
Note: size of bullet cannot be determined

19. Death Investigation > Traumatic Death > Mechanical > Firearm Wound
Entrance vs. Exit wound
Typically, entrance wound smaller than exit wound.
Reason: nothing behind exit wound to prevent explosive burst.

20. Death Investigation > Traumatic Death > Mechanical > Firearm Wound
Entrance vs. Exit wound
Exception is if exit wound is shored. Tight fabrics or body against object prevents the “explosive outburst”.
Shored exit wound looks like entrance wound (which is always shored by body)

21. Damage relates to kinetic energy
Death Investigation > Traumatic Death > Mechanical > Firearm Wound
Damage relates to kinetic energy
Exiting bullet “wastes” kinetic energy
Hollow point bullets designed to expand and stay in body longer; in reality not much difference.

22. Damage due to rebounding tissue
Death Investigation > Traumatic Death > Mechanical > Firearm Wound
Damage due to rebounding tissue
Bullet too fast to tear tissue; pushes tissue aside creating cavity.
Tissue tears upon rebound, along with some surrounding tissue.
Damage about 3x diameter of bullet

23. Mechanical (blunt force – non-firearms)
Death Investigation > Traumatic Death
Mechanical (blunt force – non-firearms)
Most common are car accidents
For homicide (beatings) almost always involves a blow to the head.
Mechanism of death: usually drowning in blood

24. Mechanical (blunt force – non-firearms)
Death Investigation > Traumatic Death
Mechanical (blunt force – non-firearms)
Rarely will one blow to the head knock a person unconscious.
Book fails to mention vulcans.

25. Mechanical (blunt force – non-firearms)
Death Investigation > Traumatic Death
Mechanical (blunt force – non-firearms)
Contusion: accumulated blood in tissues outside the blood vessels (internal bleed)
Hematoma: large contusions (blood tumor); goose egg on head

26. Death Investigation > Traumatic Death
Chemical Trauma
Overdoses: depressants (including alcohol) slow communications. Can cause coma.
Stimulants may cause seizures and death, less common.

27. Death Investigation > Traumatic Death
Chemical Trauma
Carbon Monoxide: binds hemoglobin, blocks oxygen. Kills by asphyxiation.
Other poisons interfere with a variety of essential biological functions.

28. Thermal Trauma Hypothermia: excessive cold
Death Investigation > Traumatic Death
Thermal Trauma
Hypothermia: excessive cold
Hyperthermia: excessive heat
Both hard to diagnose
Death from fire usually due to carbon monoxide poisoning.

29. Death Investigation > Traumatic Death
Electrical Trauma
Heartbeat relies on electrical signals from the brain.
Low voltage causes heart to “quiver”, then stop.
Extremely high voltage causes heart to contract, then start beating again.