FSE09
forensic ento mology
Case Studies
Teacher background information
History of forensic entomology
Forensic entomology is not a new science. The first
recorded case of forensic entomology was in China
in 1235 AD. After a person was found dead, all the
peasants in the village were required to bring their
farming tools to the village centre. The killer’s weapon
was identified because there were flies feeding on the
tiny amounts of blood attached to the tool.
Case Study 1
The skeletal remains of the buried young girl from
Hawaii (adapted from ‘A fly for the prosecution: how
insect evidence helps solve crime’ by M. Lee Goff)
The remains of a female child (30 months of age) were
recovered from a shallow grave on a narrow ledge
in Oahu, Hawaii. The remains were buried in dirt and
gravel, and some bones were partially exposed. Other
bones were scattered on the surface. The skull was
facing upward, and the lower jaw was located about a
meter from the skull.
The pathologists at the morgue examined the body
and found the girl’s skull, jaw, most of the ribs, the
pelvis and legs and left arm. The right arm was
missing. Small bones of the left foot appeared to have
been chewed and so did the bones of the left forearm.
This indicated that a large animal had attacked the
body after death. The girl was wearing a hooded
jacket and a pair of running shoes. The next day, the
girl’s right arm was found at the burial site.
The body was examined but only a small number of
insects were found on the body. Empty puparial cases
(cocoons) of the calliphorid Chrysomya rufifacies (a
type of blow fly) were attached to the skull under the
scalp, which had largely been eaten away.
Adult dermestid beetles, Dermestes maculatus, were
present on the bones, and third instar larval skins of
that species were observed in areas under the scalp,
inside the skull, and on the leg bones. The larval skins
of the dermestid beetles were in good condition and
did not appear to have been exposed to the weather.
Larval scenopinids (Diptera - flies) were collected
from the scull near the bases of the hair. Adult clerids,
Necrobia rufipes, were recovered from the bones of the
left foot. A silverfish (Thysanura: Lepismatidae) was
recovered from the body bag.
In the hood of the jacket, there was a small amount
of soil. More larval scenopinids and adult dermestid
beetles were found in the soil when it was sorted by
hand. The forensic entomologist also found an adult
histerid beetle and mites.
The forensic entomologist estimated a PMI of 52-76
days by comparing the results with other data already
collected. This estimate was lowered to slightly over
52 days, based on the condition of the larval skins of
the dermestid beetles, which were in good condition.
The mites recovered were also consistent with this
time frame, and because other mite species weren’t
present, the forensic entomologist reckoned the time
since death to be closer to 52 days.
In the decomposition studies used for comparison,
the last observed larval activity for dermestid beetles
was on day 51. Usually, the larval skins decompose
rapidly when exposed to the weather. The fact that
these skins were in excellent condition and could
easily be identified indicated that they had been shed
recently.
In the meantime, police investigators were dealing
with conflicting accounts of the crime. On 3 May,
the girl’s father stated that his daughter had been
kidnapped on the night of 2 May. He said that two
men forced him and his daughter into a car, dropped
him off in Honolulu and beat him. He said the
kidnappers ran off with his daughter. The father was
treated at the hospital for injuries. According to the
father’s story, these events occurred 51 days before
the discovery of the body.
When the story appeared on the news, two men came
forward and told the police that they had beaten
the father but that he had paid them to do so. When
the father heard the men’s story, he changed his
own story. He told police that he was hiking with his
daughter on 2 May but had slipped and dropped the
girl over a cliff. He said that he tried to revive her but
failed and buried her in a shallow grave. He admitted
that he made the kidnapping story up.
The police did not believe the father’s accident
story and charged him with murder. By the time
of the trial, the father had changed his story again.
The only aspect of the case that had not changed
was the time of death estimate that the forensic
entomologist provided. The jury accepted the forensic
entomologist’s testimony but did not believe the
father’s story. Potentially, the father’s story could have
fit in with the estimated time of death but he was
not credible to the jury. The father was charged with
murder and is serving a life sentence.
FSE09
forensic ento mology
Case Studies
Case Study 2
Case Study 3
http://research.missouri.edu/entomology/casestudies.html
Robert Donald Auker was convicted of the murder
and kidnapping of his former wife Lori Ann Auker.
Lori Ann’s body was discovered on a hot day, 12 June
1989 by a young woman who was walking down a
dirt road near her grandparent’s house. She smelled
a bad odour, investigated and found a decomposing
body wearing a jacket, jeans and sneakers. She
rushed home and her family contacted the police.
The pathologist, Dr Mihalakis testified to the court
that the cause of death was homicide, most likely
between seven and ten knife stab wounds in the back
and chest area. Dr Mihalakis used Dr Kim, a forensic
entomologist, to confirm the approximate time of
death.
A few years ago, on 4 June, the body of a girl was
found alongside a rural highway in North America. An
autopsy revealed that she had died of multiple head
and neck wounds inflicted by a heavy sharp object.
Her brother had reported her missing approximately
4 days prior to the discovery of the corpse. She had
last been seen alive on the morning of 31 May in the
company of a 30 year old army sergeant, the primary
suspect. While considerable circumstantial evidence
supported the theory that the victim had been
murdered by the sergeant, an accurate estimation of
time of death was crucial to establishing a possible
link between the suspect and the victim at the time
when death occurred.
Several estimates were offered by medical examiners
and investigators. These were based largely on the
physical appearance of the body and the extent to
which decomposition had occurred in various organs.
Numerous fly larvae, adult flies and other insects were
collected from in and around the victim’s wounds.
Some of the larvae were collected alive and reared to
produce adult flies for species identification. Others
were placed immediately into a liquid preservative to
identify the developmental stage. Reports describing
the condition of the body when found and detailing
autopsy procedures and results were reviewed.
Weather data, including maximum and minimum
temperatures, incidence of rainfall, cloud cover, wind
speed and direction, and relative humidity were
obtained from a weather station located a short
distance from the crime scene. These data indicated
the environmental conditions to which the body and
its associated insects were exposed.
Based on this total array of evidence, entomologists
determined that the first insects to colonize the body
had arrived on May 31 when the accused was found
with the victim. On questioning he admitted to have
murdered the girl by striking her six to eight times
with a small hatchet sometime around noon on May
31. Subsequently, he entered a plea of guilty to the
murder charge and was sentenced to life in prison
without parole.
Dr Mihalakis collected the insects present on and
within the corpse and gave them to Dr Kim who
examined them. Dr Kim stated in court that he was
able to estimate the time of death by analysing
the insects. He explained that the ambient air
temperature and the physical site of the body affected
the rate of development. Dr Kim used a climate report
from the national weather service and a description of
the autopsy and scene to help determine the time of
death.
Dr Kim identified samples of insects found on the
victim and examined a photograph showing a mass
of insects on the body and in the body bag. Dr Kim
took the average temperature during the time the
body had been missing, the maturity of the insects
present and the stage of decomposition into account.
He determined that the body had been decaying for
between 19 and 25 days.
Lori Auker was identified using dental records and
was last seen wearing clothing like that found on the
corpse. Robert Donald Auker was connected to the
crime by film from an ATM video camera film from 24
May (the day Lori went missing) and through strands
of cat and human hair. Photographs of the corpse
and insects were presented to the jury to assist in
their understanding of forensic entomology. Robert
Donald Auker received a death sentence upon his
conviction. Forensic entomology helped estimate
the time of death (19 days), which aided in the jury
convicting Robert Donald Auker of murder.
FSE09
forensic ento mology
Case Studies
Case Study 4
http://research.missouri.edu/entomology/casestudies.html
In November a partially clad woman’s body was found
by passing motorists in a wooded area approximately
50 feet from a well-traveled highway in suburban
Washington, DC. The deceased was a young, adult
black female, weighing approximately 116 pounds.
Her body was cold, rigor mortis was absent, and
only minor external decompositional changes were
evident. The victim had died of multiple stab wounds
to the chest and neck.
During the autopsy, several large maggots were
observed migrating away from the corpse. This
behavior is characteristic of fully developed, postfeeding blow fly larvae. Several additional maggots
were removed from the neck wounds and clothing.
The victim was subsequently identified as a 21
year-old mother who resided with her infant and
parents in an urban apartment complex in southeast
Washington, DC. She had been reported missing by
her parents 18 days prior to the discovery of her body.
She was last seen alive during the early morning hours
on Wednesday, 26 October in the apartment of the
primary suspect, who had a history of sex-related
offenses and violent crimes and had recently been
released from prison.
Witnesses recalled having seen a man and woman
struggling and having heard a woman screaming
in the vicinity of the apartment house during the
early morning hours 18 days prior to her discovery.
Hair from the victim’s head and pubes was found
on bed sheets in the suspect’s apartment. A shoe
belonging to the deceased was subsequently found
in a secluded urban woodlot located a short distance
away. Samples of blood and hair taken from the
suspect’s car also were identified as belonging to the
victim. An analysis of auto carpet fibers, removed from
the victim’s clothing, further demonstrated that she
had been transported in the same vehicle.
While considerable circumstantial evidence pointed to
the suspect, an accurate estimate of the time of death
was critical in establishing the sequence of events
surrounding the death. Several conflicting estimates
of postmortem interval, varying from 2 to 8 days, were
offered by medical examiners and case investigators,
based primarily on the physical appearance of the
body and the extent to which autolytic changes had
occurred within various organs.
The maggots observed in and around the body
during the autopsy were identified. Rearing of
maggots to the adult stage was not possible as
none of the specimens had been maintained alive.
Soil samples yielded no additional specimens.
Numerous photographs depicting the crime scene,
the surrounding vegetation and terrain, and the body
itself were examined.
Climatological data, including maximum and
minimum temperature, cloud cover, rainfall, wind
speed and direction, and relative humidity were
obtained from a National Weather Service (NWS)
observatory located less than a quarter of a mile from
where the victim’s body was found. Additionally,
reports describing the condition of the body when
found and detailing autopsy procedures and results
were reviewed.
The largest fly larvae inhabiting the remains were
fully engorged third instar larvae and post-feeding
larvae of Calliphora vicina. One specimen showed
morphological signs of pupation.
Based on the temperature records for the relevant
period, the number of days necessary for Calliphora
vicina to develop from egg to prepupa was calculated.
Because the average daily temperature to which
the developing flies were exposed was cool (10oC)
and because too few larvae were present within the
corpse to elevate microenvironmental temperature,
the postmortem interval was estimated to be 15 days.
Based on the entomological data and the other
evidence acquired during the police investigation,
the suspect was arrested and charged with first
degree murder, kidnapping, and felony rape. He
was eventually tried, found guilty of all charges, and
was sentenced to a lengthy prison term. Later it was
learned that he had murdered the victim during the
early morning 18 days prior to discovery and had
hidden the body, by covering it with tree branches, a
mattress, and other debris, in a nearby urban woodlot.
Three days later, again during the early morning
hours, he had transported the corpse to the location
where it was found. The materials used to hide the
body may have prevented oviposition by adult
Calliphora vicina during the first few days following
death. The fifteen day postmortem interval was valid.