Why is the medical examiners autopsy completed within 24 to 48 hours of a homicide?

The coroner may order a post-mortem examination to determine the cause, identification of the remains, document injuries, and to assist in determining the manner of death. A coroner usually orders a forensic autopsy if foul play is suspected.

Explanation:

The 24- 48 window is a good time for everything to still be the same it was after the incident therefore no more further injuries could happen  and everything is still "fresh".

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