According to the North American Entomology Association, it is easy for investigators to attribute postmortem damage to a body due to insect activity to antemortem occurrences.
Studies have shown that the insects that feed on decaying bodies often leave behind marks or abrasions that can be misinterpreted by investigators.
A recent study conducted at the Forensic Anthropology Center at Texas State found that postmortem arthropod activity can often mimic antemortem wounds. In this study the arthropods left marks on a decaying body that could be “misinterpreted as attack, abuse, neglect, or torture.”
The study also found that arthropod activity could be “misidentified as sources of intravenous drug use, bite marks, [or] defensive wounds.”
This study in particular noted the previously undocumented activity of katydids and isopods on decaying corpses. The study noted that the small openings made by katydids and red ants could be mistaken for marks and abrasions that occurred before the person died.
Another study was conducted by entomologist Natalie Lindgren at the Southeast Texas Applied Forensic Science Facility. Lindgren spent a year observing, photographing, and collecting the insects feeding on decaying corpses.
Lindgren noted the unusual presence of scorpion flies in the early stages of decay. The scorpion flies remained for the first day and a half of decay. Discovering which insects arrive first and how long they stay allows investigators to determine when the person died.
The observations of entomologists in both of these studies offer crucial information for investigators. The presence and activity of various insects can be both helpful in determining when a person died and detrimental by mimicking other antemortem damage to the body.