1. Shoot Around
Explain the difference between rigor mortis, algor mortis, and livor mortis.
If a person’s body temperature is typically 37 degrees Celsius and the person will typically about 1.5 degrees per hour after death, then how long was a person dead if their body was 28 degrees when it was found?

2. Methods to Determining Death Review
Objective: Students will describe how and why the dead body of a victim contains an abundance of evidence that can be used to identify the mechanism of death
Essential Question: How can we use the body temperature, body stiffness, and body color to determine the time of death?

3. Manner of Death Four ways people die Natural Accidental Suicidal
Interruption and failure of bodily function resulting from age or disease
Accidental
Unplanned event
Suicidal
A person purposely kills oneself
Homicidal
Death of one person caused by another

4. Example
A man was shot in the head, which led to exsanguination and brain death. What is the manner of death?
Homicide due to the gun shot.

5. Your Turn!
A woman smoked since she was 19 and died at the age of 65 of lung cancer, which caused her to go into respiratory failure. What is the manner of death?

6. Algor Mortis Uses body temperature to determine time of death
Normal body temperature is 370C (98.60F)
A body loses heat at a rate of 1.40C per hour until the ambient temperature is reached
Rate varies according to environmental temperature
Once ambient temperature is reached, you cannot use this method to determine time of death

7. Question: What are some Factors that would affect Algor Mortis?
Ambient temperature
Wind?
Excess body fat?
Clothing

8. Question: What are some Factors that would affect Algor Mortis?
Ambient temperature
Wind?
Excess body fat?
Clothing

9. Think-Pair-Share
Why is algor mortis a difficult method to use when determining time of death?
First, take two silent minutes to think of answer
Second, take two minutes and talk with an elbow partner about your thoughts
Third, three groups share your thoughts to the class

10. Rigor mortis: The medical condition that occurs after death
Results in the shortening of muscle tissue and the stiffening of body parts
Body stays in the position they are in when death occurs
Begins within 12 hours and ends after 48 hours
After 48 hours, muscle cells begin to autolyse 10 10

11. Rigor Mortis Time Event Appearance 2-6 hours Rigor begins
eyelids, Jaws stiffen
After 2 hours
then center of body stiffens
12 hours
Complete Rigor
Entire body rigid
15-36
Slow loss of rigor, small muscles first
Lost in head and neck, last is bigger leg muscles
36-48
Rigor disappears, muscles become relaxed

13. Livor mortis
* Is a settling of the blood in the lower portion of the body
** Causing a purplish red discoloration of the skin.
*** Discoloration does not occur in the areas of the body that are in contact with the ground or another object,

14. 3. Livor mortis

15. Autopsy and time of death cont…
Livor mortis: the medical condition that occurs after death and results in the settling of blood in areas of the body closest to the ground
Evident minutes postmortem
8-12 hours (24-36 hours in cooler temps) postmortem- maximum color or “fixed” livor mortis due to hemolysis (blood vessels break down)
May occur antemortem (before death) in slow deaths
Can congest internal organs 15 15

16. Potassium levels in vitreous humor + Clouding of the cornea
Cornea is the clear covering of your eyes
Becomes cloudy and opaque after death
Takes only a few hours after death if eyes are open at death
It takes 24 hours if eyes are closed at death.
Cornea

17. Potassium levels in vitreous humor + Clouding of the cornea
Vitreous humor is the jelly like fluid found in the eye.
Concentration of potassium increases slowly during first few days
Vitreous humor

18. 5. Stomach Contents

19. Stages of Decomposition
Initial decay
Corpse appears normal, internal bacterial decay and autolysis begins
Putrefaction
Odor of decaying corpse swollen
Black Putrefaction
Very strong odor, flesh appears black, gases escape, corpse collapses
Dry Decay
Corpse is almost dry, further decay slows from lack of moisture

20. Stages of Decomposition
2 days
Cells autolysis
Greenish purple staining occurs, blood decomposing
Skin takes on Marbled Appearance
4 days
Skin blisters
Abdomen swells with carbon dioxide
Due to bacteria in intestines
6-10 days
Corpse bloats with CO2
Corpse eventually bursts
Fluid begins leaking from openings as cell membranes rupture
Eyeballs liquefy
Skin sloughs off