Chapter 12 Death: Manner, Mechanism, Cause
Student Learning Objectives
Forensic Science: Fundamentals and Investigations, 2nd ed., Bertino & Bertino, 2015
At the conclusion of this chapter, the student should be able to:
Death
_____1. What are some different definitions of death?
_____ 2. Discuss why it is challenging to determine the precise moment of death.
_____ 3. Distinguish between cellular death and death of the organism.
_____ 4. Distinguish among cause, manner, and mechanism of death.
_____5. Describe the four manners of death, natural, accidental, suicidal, and homicidal,
as well as the fifth classification, unknown.
_____6. Explain the significance of determining the manner of someone’s death.
_____ 7. Distinguish between the roles of medical examiners and coroners.
Decomposition
_____ 8. Discuss the immediate effects of death. Include in your answer:
a. heart
b. circulation
c. oxygen and glucose levels of the blood
d. body temperature
_____9. Describe the chemical and physical processes that occur in cells as circulation to
them ceases in the early stages of death, preceding autolysis. In your answer,
discuss
a. circulation
b. oxygen levels
c. aerobic respiration
d. anaerobic respiration
e. cellular wastes and lactic acid
f. release of cellular enzymes
g. cell membranes
h. enzymes
____ 10. Discuss the process of autolysis:
a. What is autolysis?
b. Why is it appropriate to refer to autolysis as “cell demolition”?
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c. What causes cells to undergo autolysis?
_____11. Describe the chemical and physical effects of the marbling of the skin that
occurs during decomposition. Include in your answer:
a. the breakdown of capillaries and body cells
b. protein and hemoglobin
c. sulfurous waste products
d. seepage between cells
_____12. Account for the reason(s) that it is difficult to determine skin color and ethnic
backgrounds on decomposed bodies.
____ 13. Describe the chemical and physical effects that explain the skin slippage that
occurs during decomposition. Include in your answer:
a. bacteria
b. waste gases
_____14. Relate the process of putrefaction to the decomposition of tissues. Include in
your answer:
a. bacteria
b. body tissues
c. foul-smelling gases
d. waste products
_____15. Describe the distinguishing characteristics of the following stages of
decomposition:
a. initial
b. bloating
c. active decay
d. advanced decay
e. dry decay
_____ 16. Recognize the stage of decomposition based upon:
a. absence or presence of odors
b. amount of decay
c. accumulation of decomposition gases and bloating
d. marbling of the skin
e. color of the flesh
f. seepage of body fluids
g. dryness of the flesh
h. mostly skeletal remains
______17. Describe the effect of the environment on the rate of decomposition:
a. body clothed or naked
b. temperature
c. wind
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d. body exposed to the air, buried or submerged in water
e. illness at time of death
f. body weight
g. body size
______18. Discuss the postmortem interval "rule of thumb" and account for the changes
In body temperature and the rigid or flaccid (relaxed) muscle conditions.
a. warm body and limp (less than 3 hours)
b. warm body and stiff (3-8 hours)
c. cold body and stiff (8-36 hours)
d. cold body and limp (over 36 hours)
Postmortem Interval
______19. Distinguish between time of death and postmortem interval (PMI).
______20. Explain the forensic significance of estimating the postmortem interval.
______21. List four different techniques that help estimate the postmortem interval
(PMI).
Livor Mortis
______22. Describe what happens to the body as livor mortis develops.
Include in your answer:
a. blood and blood vessels
b. circulation
c. decomposition
d. gravity
______23. Explain when lividity first appears and when after death it becomes
permanent.
______24. Explain how it is possible to determine someone’s body position at the time of
death.
______25. Explain the forensic implications of finding a body exhibiting dual lividity.
______26. List the drawbacks of estimating postmortem interval using lividity only.
Rigor Mortis
______27. Define rigor mortis.
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______28. Describe the progression of rigor mortis from when it first sets in to when
fades.
______29. Compare and contrast the shape of muscles during rigor mortis versus when
they are relaxed.
______30. Describe the biochemical causes of rigor mortis.
______31. Explain the role of each of the following in regards to rigor mortis:
a. oxygen
b. circulation
c. aerobic respiration
d. anaerobic respiration
e. acetic acid
f. energy production
______32. Explain what causes the loss of rigor.
______33. Describe the effect of each of the following variables to the onset of rigor
mortis:
a. body temperature
b. ambient temperature
c. amount of body fat on the victim
d. amount of clothing on the victim
e. illness
f. amount of exercise prior to death
______34. List the drawbacks of estimating postmortem interval using rigor mortis
evidence only.
Algor Mortis
______35. Define algor mortis.
______36. State the formula used to estimate the loss of body temperature after
a. the first 12 hours after death
b. after 24 hours after death
______37. Explain how body temperature is taken from a corpse.
______38. Describe the effect of each of the variables on loss of body temperature:
a. ambient temperature
b. presence or absence of clothing
c. exercise prior to death
d. amount of air circulation
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______39. List the drawbacks of estimating postmortem interval based on the loss of
body temperature only.
Forensic Entomology
______40. Describe how to estimate postmortem interval based on insect evidence found
on the body and at the crime scene.(Refer to Chapter 11 Forensic Entomology
for more Student Learning Objectives on this topic.)
Other Evidence Used to Estimate Postmortem Interval
______41. Explain why the gastric contents are emptied and examined during an
autopsy.
______42. Explain why knowing the degree of digestion of the gastric contents of a
deceased person is useful in estimating postmortem interval.
______43. Describe changes in the cornea following death. Include in your answer when
these changes depending on whether the eye is closed or open at the time of
death.
______44. Discuss the reliability of measuring potassium levels in the vitreous humor of
the eye for estimating postmortem interval.
Autopsy
______45. Explain the purpose of an autopsy.
______46. Who performs autopsies?
______47. When are autopsies required?
______48. Discuss the basic procedural steps of an autopsy.
______49. Describe the forensic information gained by the following procedures
performed at an autopsy:
Organ and blood vessel examination:
a. emptying of stomach contents
b. macroscopic and microscopic examination of the liver
c. examination of bullet wounds
d. examination of knife wounds
e. examination of the blood vessels and heart
f. examination for bruising
g. examination of the hyoid bone in the neck
h. examination of genitals for tears, cuts, body fluids
i. X-ray of body
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j. examination of the brain
k. removal of fluid from the bladder
l. removal of fluid from the inside of the eye
External examination:
m. evidence of algor mortis
n. evidence of rigor mortis
o. evidence of body fluids: blood, saliva, semen, vaginal fluid
p. removal of any insects found on the body
q. scraping and removal of anything under the fingernails
r. examination of the eyes
s. examination of body for any cuts, wounds, or bruises
t. examination for evidence of broken bones
u. examination of skin: color, rashes, bites
v. examination of genitals
General Information
______50. Given insect evidence; data pertaining to rigor, algor, and livor mortis; and
data from the autopsy, be able to estimate PMI.
______51. Explain how postmortem interval is an estimate that should be based on
multiple factors not just one type of evidence.
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