Death Investigation

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

6. Death Investigation Examples: • Richard Moll has purloined Marsha Warfield’s sack lunch from the set of Night Court 2010. Marsha smothers him with a pillow. Richard Moll dies. Mechanism of death: asphyxia Cause of death: smothering

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

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

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

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

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

18. 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. 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. 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. 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. 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. 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. 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.