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Flashcards in Forensic Science Deck (23)
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What is most useful for Sex Discrimination ?

Skeleton - pelvis and skull

then either prostate or uterus


Indicator of ageing from infancy to adulthood

examining the teeth


Determination of age - Childhood and adolescence



... are very useful in determining foetus and neonate (age)


Bone development assessment using ossification centres
24 GW (Gestation Weeks) and term are of most frequent interest


.... are most useful for calculation of height

Individual bones of the lower limb

long bones - good


In a Mass Fatality Incident, maximum benefit can be gained by helping investigators.....

reconstruct the incident


Death is defined as

the irreversible failure of the CVS


Can the rate at which the stomach empties be used as a means of measuring the time of death - or the time since the last meal?


Too many factors influence the rate at which the stomach empties, e.g. nature/amount of food, solids vs liquids, stress, certain medication

Can offer information on what the deceased last ate depending on the condition of the material remaining

Stress can prevent stomach emptying


Stiffening and shortening of muscle fibres leading to rigidity of the musculature and fixation of the joints

Rigor Mortis

reduction of adenosine triphosphate (ATP) within the muscles after death

calcium builds up in the muscles, causing them to tense

therotecically detected in smaller muscles before larger muscles

becomes apparent 5-7 hours after death
usually full established by 8-12 hours
36 hours after death - body in flaccid state


A process of “dry” decomposition, with desiccation of the body and a relative lack of bacterial involvement


Body essentially “dries out”; the facial features and hands/feet may become rigid
Preservation may be remarkable
Infant bodies particularly prone to mummification


Caused by the action of bacterial micro-organisms; process begins at death, but takes a period of time to become detectable


rem by (petri - bacterial)


Induced by the hydrolysis of fatty tissue within the body into a greasy/waxy or brittle material which frequently remains attached to the bony skeleton and may retain the body structure to some extent

Adipocere formation

Tends to occur in damp or wet environments, e.g. bodies recovered from water


The condition when all of the soft tissues of the body have completely degraded


The process is extremely variable: main variables are exposure to meat-eating animals (post mortem animal predation, e.g. rats) and to dipterous larvae
Radioisotopes have been used to “age” bones, recently including strontium and polonium


Represents the pooling of Stagnant blood in dependent regions of the body under the influence of gravity

Post mortem hypoStatis

Usually readily apparent on the external aspect of the body, but may also be observed in the internal organs

Begins as soon as the circulation of blood ceases, but takes time to become visible, usually about 1-2 hours, and fully established by 6-12 hours

not for timing death


hypostasis (Red/brown) - may be seen with

methaemoglobin (caused by certain chemicals or drugs)


hypostasis - Cherry red colour

indicator of carbon monoxide poisoning


Colour of hypostasis can occasionally be

Usually pink/purple in colour


Alteration or damage to the body occurring after death which may mimic genuine processes occurring in life

Post mortem Artefacts

• Resuscitation (cardiopulmonary resuscitation - CPR)
• Animal predation (land and sea)
• Traumatic injury


cooling - room temp - 1C every hour (sigmoid curve)
circulating blood becomes stagnant - falls under gravity - 1-2 hours
putrefaction - process begins at death, detectable in days
rigor mortis - begins 5-7 hours
skin shrinks
body green 2-3 days
blister formation and tissue swelling - gas formation 1 week

stages of death


gold standard comparative methods

dental records

med information


oppportunity for timing of death

first 18 hours


measurement of core body temp

first 12 hours


timing of death - aL-Alousi and Henssge

accuracy of no better than +/- 2.5 hours

precise timing not possible