Examiners involved in legal medicine are frequently asked questions relating to the precise time of death and they investigate early postmortem changes which are useful to estimate of the time of death. However, it is one of the most difficult
problems
because postmortem changes are various and examinated results are subjective.
One of early postmortem changes, the rate of cooling of the body after death can be measured with rectal thermometer, therefore it is relatively objective. The fall of the body temperature after death depends on Newto's law of cooling that the
curve of
them has a sigmoid shape with an initial plateau of slow cooling, followed by a relatively straight portion of varying length and a slope corresponding to the period of quickest cooling and finally a slow falling curve of gradually decreasing
gradient.
And there are several formulae which can be used in estimating the time of death with rectal temperature. But the rate of cooling of dead body is affected by many factors such as cause of death, physical factors of copse, environmental factors,
naked or
clothed condition of corpse,. etc.
Conclusively, it is clear that no formulae is yet known which can help determine the exact time of death because of variable factors influencing on the rate of cooling of body after death. The estimation need not limited to the measurement of
postmortem
temperature, but should be based on careful evaluation of all findings. Also, examiners need not claim that their or other's result is exact or not.
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