Forensic Entomology: History, Benefits and Limitations
Although the many uses of forensic entomology has become popular as a science, it wasn’t always so. The presence of insects in crime scenes, residences, buildings and gardens were once just considered natural occurrences and were largely ignored. However, it wasn’t long before their use as evidence of crime, neglect, chemical misuse or mishandling gave way to the science we now know as forensic entomology.
Today, forensic entomology is an important part of forensic medicine and many legal investigations. Scenes of crimes, for example, sometimes make it difficult to determine the time of death of a victim. However, it can be assisted with the information provided by the identification of insects found in the scene.
Forensic entomology scientists are also called entomologists and are often asked to investigate a location or a crime scene to collect, analyze and preserve insect evidence. This field of study is fast becoming one of the most popular sciences in forensics and many entomologists are often asked to become expert witnesses in both civil and criminal proceedings.
What is forensic entomology?
Forensic entomology is the science that deals with the study of insects to determine their link as evidence to certain events, some of which may be related to crime. Forensic entomology has three subfields: medicolegal or medicocriminal, stored-product and urban forensics.
Medicolegal forensic entomology
This field of forensic entomology is the study of the involvement of insects and arthropods in events like murder, physical abuse, suicide, rape, even contraband trafficking. Forensic entomologists can estimate a portion of the PMI or postmortem interval and sometimes, location of death by determining which insects appear in which location in a dead body and in what order.
This investigation also helps entomologists determine possible use of insects in criminal activities. It is often linked to other fields related to medical entomology, forensic pathology and taxonomy.
Stored-product forensic entomology
This field of forensic entomology deals with the study of insect contamination or infestation of foods and food products that are commercially sold or distributed. Stored-product forensics is usually used in legal proceedings in matters related to problems caused by product contamination by insects.
Urban forensic entomology
This is the study that involves pest infestations in residential or commercial buildings, gardens and other structures. This often involves insects such as termites, ticks, ants and cockroaches. Investigation of how insects are involved is often used in litigations involving residents or occupants and service companies like pest exterminators or landlords.
History of forensic entomology
Entomology had its rough beginnings in 4th century B.C. However, as a science, entomology only began to develop in 17th century A.D. It improved further in the 19th century, thanks to Charles Darwin’s ‘Origin of the Species’. Entomology’s application to forensics, however, has had its share of ups and downs, beginning as early as 13th century in China. In 1668, experiments performed by Francesco Redi with rotting meat yielded the observation that the development of blow flies later produced maggots. Up until that time, it was believed that insects such as maggots developed from the rotten meat itself.
In 1855, Bergeret, an investigator in France, used insects to determine the time of death of an infant, the body of whom was hidden behind a plastered mantle in a house. His investigations subsequently proved that the guilty party was not the present occupants of the house but the previous owners, based on the presence of insects on the dead body. In the years that followed, further research and publications helped people realize the importance of forensic entomology to forensic investigations.
As years passed, further research about forensic entomology soon led to the refinement of the science and its application in a variety of fields became apparent. Today, only qualified entomologists may be capable of identifying and analyzing insect evidence although it may be collected by other police personnel, including medical examiners and crime scene technicians.
Advantages and limitations
In civil investigations or litigations, forensic entomology can be an excellent tool to help establish misuse or neglect should insect infestation occur in buildings such as residences and offices, in which case occupants may have the evidence to use when filing a complaint against their landlords or pest exterminating companies. Forensic entomology can also determine manufacturing or retail malpractices that may result to insect infestations of stored food commodities.
Thanks to some media exposures from TV shows and articles, forensic entomology has had its share of hypes and expectations. However, it does have certain limitations. In crime scenes, for example, forensic entomologists cannot estimate the time of a person’s death. What they can do is to provide an estimate of the minimum postmortem intervals. Many of the studies performed with insects are made under controlled conditions so only the minimum time of insect development may be inferred. Additionally, locations where these insects are found are often less than the ideal or perfect environment found in controlled study rooms. Furthermore, there is the factor of delay in the insect’s arrival. It is also difficult to ascertain whether or not chemicals such as alcohol, medication or pesticides can be quantified in insects.
Forensic entomology is still not a near-perfect science but its contributions to the resolution of many civil and criminal cases are appreciated. We can only hope that further improvements in methods and techniques involved in data and sample collection and analysis will create a more reliable and accurate science.
