Forensic Entomologist

Case Study: Maggots On Trial

A dead body is found by some mushroom hunters in a patch of weeds near highway 47 in southeast Indiana. Police link the body to a report of a 27 year old female who has been reported as missing. Homicide detectives arrive to process the crime scene. They note that the body is laying face down with obvious gunshot wounds to the head and torso, and that there are many fly larvae (maggots) present.

Police investigators are immediately dispatched to question the victim's family and friends. The victim’s brother recalls seeing his sister seven days earlier with her boyfriend and that they seemed to be arguing at the time. The boyfriend is brought in for questioning and says he was with her as recently as 2 days ago and that they had resolved all their problems of the previous week. However, the boyfriend says that his girlfriend has not contacted him for two days. He says he is very worried about her.

The police suspect foul play on the part of the boyfriend but have to be able to formulate a 'time of death' time frame. They have access to a forensics laboratory that can provide climatological data (air temperature, wind speed, and relative humidity) for the area in question. They suggest contacting a professional forensic entomologist.

A forensic entomologist is immediately called to the site. He collects some of the larvae found on the body and returns to his laboratory to conduct tests. His final report, based on the evidence he collected, is that the time of death was between six and eight days earlier. This report, along with other key pieces of evidence, lead to the arrest of the boyfriend.

In court, the forensic entomologist is asked what the basis is for his report and how fly larvae could possibly determine the young woman's time of death. The forensic entomologist provides the following answer: Entomologists have studied the attraction a dead body holds for insects and have worked out their natural succession on a decomposing body. Based on the identity of the fly species, the developmental time period of the various larval forms, and the temperature data in the surrounding area, the time of death can be worked out very predictably and with a high degree of certainty. In this specific case, the fly larvae would have required 6-8 days to reach the stage in which they were found on the body. Given the evidence, it is clear the woman could not have been alive two days previous to the discovery of the body, as the suspect has stated.

Faced with the testimony provided by the forensic entomologist and other key pieces of evidence, the boyfriend confesses to killing the victim and is convicted of committing the crime of murder.

Summary

Students of entomology who have an interest in problem-solving, law enforcement and who have a strong stomach can specialize in forensic entomology. Forensic entomologists deal with the law and are usually called upon to reconstruct entomological events to solve problems. This includes, but is not limited to, murder investigations.

Forensic entomologists investigate complaints of human injury, disease, food contamination, plant injury, and structural damage caused by insects. Practical entomology and problem-solving is almost always followed by testimony in a court of law. This requires a person to be very precise, accurate, and verbally explicit. Skills in public speaking and writing are required, and forensic entomologists must be confident in their abilities because cross-examination can be very critical.

Some forensic entomologists work in law enforcement, while others work in private consulting. Most forensic entomologists are affiliated with a university because a Ph.D. provides the credentials that an expert witness needs.