1. Body Decomposition the form and rate of decay varies
The time of physiological death is usually a “best guess”
Exact time of death cannot be accurately determined – there are too many variables

2. Time of death may be determined by…

3. 1. Body Temperature Also known as Algor Mortis
After death, the body loses heat at a rate of 1.5 degrees/ hr until it reaches ambient temperature (same as the environment)
But… Rate of temperature change may be altered by:
- weight / size
- clothing
- sun exposure
- illness
- infestation

5. 2. Rigor Mortis
Occurs when muscles contract as ATP (adenosine triphosphate) causes the release of calcium into the muscle
Begins ~2 hours after death in the face/neck
Entire process takes
~8-12 hrs
Remains stiff for another
18 hrs
After another 12 hours the
muscles relax

6. What’s this ?!
How do you know?

7. 3. Mummification
When the body dries out in a hot & dry environment (low humidity inhibits bacterial growth & sucks moisture from tissues!)
Results in a leathery, dry, preserved corpse

8. The natural mummification seen here is a result of the body being in a relatively protected nonburial environment where a sufficient flow of fresh air rapidly dried the soft tissues

9. 4. Adipocere Formation
The body’s adipose tissue (fat) turns into a white, waxy, soapy substance
Most commonly occurs in moist environments and takes about 3-6 months to form
Ex. Drowning victim

10. This poor sailor drowned and was in the sea for some months before his adipocere-laden body was fished out of the briny deep. Note the condition of ear lobes and nose. Surprisingly, most of his corpse was not consumed by sea creatures

11. 5. Gas Accumulation A.k.a. Putrefaction Bacterial decay of the body
Gives off stinky gas such as CO2 & sulfur

12. 6. Lividity Also known as Liver Mortis
Darkening of the skin due to lack of oxygen in the blood
Blood pools due to
gravity
May help to
indicate if the
body was moved

14. 7. The Eyes
Corneas become cloudy over the first 24 hrs. after death (faster if eyes are open at t.o.d.)
Potassium in the eye liquid (vitreous humor) increases within the first 3-4 days after death

17. Medical Examination

18. Medical Examiner’s Job
Medical Examiner determines manner and type of death.
Examples of manner of death are:
Homicide
Suicide
Accidental
Undetermined
Examples of type of death are:
Stroke
Asphyxiation

19. Medical Examiner & Autopsy
The medical examiner is also responsible for performing the autopsy on the body.

20. Step 1 – Place a toe tag on the body and refrigerate it!

21. Step 2 – Fingerprints are taken, body is weighed, measured and x-rayed
Step 3 – Clothes are examined and stored

22. Step 4 – Fingernails are examined and scraped for suspect DNA
Step 5 – External Examination of bruises, needle marks and skin coloring, hair samples are taken

23. Step 6 – Mouth is swabbed for victim DNA
Step 7 – Collect hair samples
Step 8 – Wash the body
Step 9 - Fluid samples taken (blood, urine, semen)

24. Step 10 – Body is dissected (Y-cut) and organs are removed, and weighed
Step 11 - A sample of every organ is sent to toxicology
Step 12 - Organs are returned to body and it is sewn up