We tend to think of investigations into suspicious deaths as being a fairly modern science, but this isn’t the case. The Coroner (originally Crowner) was established during the reign of Richard the Lionheart in 1149.
This is a great article showing how the office evolved to the one we know today as the final say on whether or not a death was suspicious.
As for the earliest written treatise on forensics, believed to be published in 1248, it is amazingly still in print! The Washing away of Wrongs: Forensic Medicine in Thirteenth-Century China covers the responsibilities of the official, outlines the procedures to be followed for a medical examination and gives advice on how to question suspects (warning investigators about false accusations), and how to interview family members. The next section shows how to begin an investigation of suspicious deaths, examining the body, including orifices, looking at ways of determining whether the corpse was moved and clues to possible causes of death.
I doubt there are many books published today that will still be in print nearly 800 years in the future!
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