History
In 1855, the French entomologist Bergeret was the first scientist to view bugs in a legal context. In this case, a baby's body was found and Bergeret looked at insects on the body to determine when the child died.
Time of Death
Forensic entomology is used to determine the time that someone died. This is done when scientists examine when insects colonized on a body based on their weight and length.
The Absence of Bugs
Just as the presence of bugs can be a clue in a murder cases, the absence of bugs can also yield important information. Flies prefer sunny, outdoor locations, so if a body is found indoors with fly eggs or larvae, the body was outdoors at some point and moved.
Detection of Abuse
In some cases, insects can uncover abuse of a victim that may have been drugged or tied up. Certain types of flies are attracted to urine and feces, and their presence at a crime scene may mean that a victim was abused and left in these bodily materials.
DNA
When an insect feeds on a human body, oftentimes DNA can be extracted from its digestive system. This information can sometimes link a suspect to a victim.