Estimating the time of death for the deceased is something else that the pathologist will have to do during the course of his autopsy procedures. In addition to this he or she may be called upon at the scene of a crime whilst carrying out their external examinations to try and judge - or best guess - when the victim died.
At the Scene
It may sound silly but one of the first things to do once a crime scene has been secured and all relevant details documented; is to check for a watch. If the victim does have a watch is it broken? If it is then the watch will more than likely have stopped at the time of the individual's death, especially if they have had a heavy impact or long fall.
In these instances, which, it must be said, are quite rare the time the body was found minus the time the watch stopped working is the period of time the body has been deceased. As we have mentioned instances of this happening are rare so the pathologist is called upon to estimate the time of death to the nearest time possible.
It must be said however that the time the individual took their last breath is not necessarily the time at which they died. This may sound bizarre but taking into consideration the human body can function for a period of time without oxygen - the human brain reportedly surviving several minutes without it - then it is reasonable to assume that the time of death may not always be accurate.
Categorising Time of Death
Time of death is categorised in three ways:
Physiological time of death: The point at which the deceased's body - including vital organs - ceased to function.
Estimated time of death: A best guess based on available information.
Legal time of death: The time at which the body was discovered or physically pronounced dead by another individual. This is the time that is shown - by law - on a death certificate.
One method of estimating the time of death is to measure body temperature. The normal equation for this is:
37.5oC - 1.5 oC
This formula equates to the body temperature (37.5oC), which loses 1.5 oC per hour until the temperature of the body is that of the environment around it; known as the ambient temperature. This ambient temperature - depending on how low it is - may take minutes or hours to be reached and this is a good indicator as to how long a body has been in situ. Additionally it is worth noting that a body's temperature will drop much more slowly if the body has been exposed to extreme cold; such as being left outdoors, submerged in water or icy conditions.
The most common way of taking the temperature of the deceased is to use a rectal thermometer or to take a temperature reading from the liver, which can achieve a more realistic core body temperature.
Rigor Mortis also acts as a good measuring stick for estimating the time of death. This natural process which occurs in all of us when we die and is the natural contracting and relaxation of the body's muscles caused by changes in the body's chemical balances.
Rigor normally occurs in the smaller muscles such as those in the face and neck and will work its way down through the body as the muscles become larger. The process normally begins roughly two hours after death and can last for anything from twenty to thirty hours. It is a common misconception that rigor does not leave the body; it will after these time frames have elapsed.
Rigor is one of the most used ways of estimating death as it occurs in the body during the first thirty-six to forty-eight hours.
Here are a couple of facts for this topic= AIR TEMP-A body will cool faster on a cold winter night than on a warm summer night.BODY FAT-Fat tends to insulate the body, so the more fat a person has, the slower the body cools after death.CLOTHING-Clothing also insulate the body, so heavy clothing will slow the rate of cooling.WATER-A body in water cools mush faster than one in air. Therefore, it is difficult to use body temp to estimate the time of death for a victim found in the water.Hope these facts help some of y'all in the future if every needing this, your very welcome for theses fact I have shared with you.
skittles:D - 29-Apr-13 @ 2:35 AM
@ Lexie,the equation would be 37.5- 1.5x = final temperature. but a simpler way would be totake 37.5- final temperatureand divide by 1.5. this will give you the number of hours that have passed. subtract them from the time the body was find and that's it. example. body found at 6 pm. temperature is 34.3.so 37.5-34.3=3.2 then 3.2/1.5 =2.13. which means 2.13hours have passed. take 2.13 away from 6 pm and you get 3.47 pm. so you can assume that TOD was around 3 47 pm
motus - 13-Apr-13 @ 3:51 AM
@ kat. the estimated time of death would be around 12 pm.
motus - 13-Apr-13 @ 3:33 AM
Hi, I am a high school student, and I am competing in a competition about forensic medicine, and all I need to know is the time of Death equation, I see that you have it above, by I do not understand it. If you would please explain it a little more in depth for me please? Thank you!!! :D
Lexie - 6-Mar-13 @ 2:53 AM
I have been trying to figure out this equation for days! When my brother was found dead his body temp was 9 and I know that the surrounding temp is a factor to determine when the time of death was. However, it was in aug of 09 and he was in a house...can anyone give me some input on what they think the time of deathwould be?? Oh and 911 was called at 7:17 am and they arrived and checked him at 7:35 am...
Kat - 10-Jan-13 @ 6:20 PM
When a person dies in a hot place will the body temp raise from 98.4 to ambient which can be say102deg.faranheit ?Will the body become warm instead of becoming cold?
jai - 17-Dec-12 @ 10:18 AM
I am a student of forensics and criminalistics.I love this site.It has been so much help to me and this particular page has been so helprul.
Louise - 12-Dec-12 @ 4:27 PM
what does the time of death have to do with anything
yo! - 9-Aug-12 @ 1:07 AM
@ Gracie the estimated time of death would be around 5:20-5:30 Am
Because her body started at 37.5*C and ended 32.2*C at 9am
You would subtract 37.5-32.2= 5.3*C
5.3*C would be the total temperature her body dropped
And since a normal body would cool at 1.5*C an hour, you should divide those two numbers
3.5333... Hrs is the time that has gone past since her death
So 3.5333... Hours before 9am would be around 5:20-5:30am
But there are certain variables that go into it as well... Such as ambient temperature.... Also im not sure but electricution might raise body temperature a bit
Jarod - 19-Jul-12 @ 10:58 PM
what was the temperature of the location where the monks body was found?
pandas - 19-Jun-12 @ 3:05 AM
A Healthy lady, about 32 years old was electricuted and her heart failed due to the electric shock. The room temperature was 20 degrees and her body temperature when it was taken at 9am was 32.2 degrees.
what estimated time did she die and how did you work this out?
Gracie - 24-May-12 @ 2:37 AM
What time have Munk died if he was found dead at 9:48 am and his body temperature is 31.8?