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Insects are known to be useful in estimating time since death, but this is only possible if samples are collected and preserved correctly according to best practices. This report describes a case where an 18-year old female was found dead and during the first medico-legal investigation which determined it was a homicide, entomological samples were collected but not considered. The case was then closed with no suspect. However, 9 years after the first investigation the courts decided that the case needed to be re-examined. In doing so the new review team decided that although the remaining entomological evidence was poorly preserved some extra information may be gained from its analyses. On inspection of the remaining samples of larvae no normal morphological analyses could be conducted. Molecular analyses were combined with an unorthodox morphological analysis to provide an estimate of the post-mortem interval based on insect evidence, indicating the value of multidisciplinary approaches to both cold and contemporary cases.

The goal of this presentation is to provide information about potential capabilities and limits of forensic entomology analyses on an old case in order to determine time of death. This presentation will impact the forensic science community by underlining how our current understanding of the forensic sciences can help solve old cases and how important it is to have a DNA database of forensically important insects. Three days after the disappearance of a teenage girl from a small city in the South of Italy the corpse of a girl was found in a wood not far from that city. Immediately it was clear that the girl was murdered and moreover the crime scene appeared to be an execution. She was still clothed, but her hands and feet were tied with wire, her head was covered with a supermarket plastic bag and her eyes were hidden by a plastic tape. The murdered girl was recognized as the girl who disappeared. The autopsy noted that she was not sexually abused, but there were many contradictory observations about the cause of death. The head of the girl sustained a bloody wound and the plastic bag over her head was not sealed properly, so there was a large mass of fly larvae on the head wound and in the eyes. The entomological evidence was poorly sampled and not used at the time, instead the level of humidity of the girl’s clothes was used to determine a contradictory time of death. Many medicolegal professionals were consulted and each one wrote a different conclusion. Two years later, the investigation led to a male suspect who was found with a note written by the girl. However, after two years of imprisonment he was exonerated. The case was reopened six years later and the prosecutors who were handling the case decided to use another team of investigators and they also decided that a forensic entomology analysis might be useful to determine the time of death. All entomological samples collected during the autopsy were destroyed some years before, so the work was performed wit

On June 2001, during the afternoon an 18 years old girl disappeared from a small city in the South of Italy. Three days later the corpse of a girl was found in a wood not far from the city. She was dressed, her hands and feet were tied with wire and her head was covered with a plastic bag. The murder appeared to be an execution. The autopsy confirmed that it was the same girl that disappeared. It was determined that she was not sexually abused, but there were many contradictory observations about the cause of death. The head of the girl sustained a bloody wound and the plastic bag over her head was not sealed properly, so there was a large mass of fly larvae on the head wound and in the eyes. The entomological evidence was poorly sampled and not used, instead the level of humidity of the girl’s clothes was used to determine a contradictory time of death. On February 2003, the investigation determined a male suspect who was found with a note written by the girl. After two years of imprisonment he was exonerated. At the end of 2007 the case was reopened and the Prosecutors who were handling the case decided to use forensic entomology to determine the time of death. Entomological samples collected during the autopsy were destroyed some years before, so we worked only on reports, pictures, crime scene and autopsy video and the girl clothes. Furthermore, meteorological data from the area nearest to the crime scene was also available. Desiccated insect material (eggs and larvae) was collected from the girl’s clothes and because of the state of this evidence a morphological examination was not possible. Instead using mtDNA analyses (COI) the insect material was determined to be Lucilia sericata (determined by a taxonomist). To identify the instar of the desiccated larvae we designed an experiment whereby different stages of Lucilia sericata larvae were desiccated and then the length was calculated before and after the dehydration process. This experiment revealed that the

Per molti anni gli insetti che popolavano la superficie e gli orifizi dei cadaveri sono stati considerati solo una presenza poco gradevole del lavoro dei medici legali e delle Forze dell’Ordine coinvolte nelle indagini inerenti a crimini violenti. Ma come gli intriganti romanzi di Deawer e della Cornwell ci hanno insegnato, gli insetti costituiscono dei silenziosi custodi di preziosi informazioni sull’accadimento di fatti a volte inspiegabili. Tuttavia mentre le varie branche delle scienze criminalistiche (la biologia, la balistica, la chimica, ecc.) hanno avuto nel tempo una crescita esponenziale, affinando tecniche e metodologie, lo studio degli insetti associati alla scena criminis è stato, nel nostro Paese per molto tempo sottovalutato o addirittura ignorato. L’Entomologia Forense è un ramo della zoologia dedicata allo studio degli insetti e di altri artropodi, dal cui esame è possibile ricavare elementi decisivi per la persecuzione di un reato. Negli ultimi anni tale disciplina ha visto crescere l’interesse da parte degli scienziati forensi, dei Medici Legali e delle Forze dell’Ordine, soprattutto in Europa e negli USA, dove esistono figure professionali specialistiche che affiancano la magistratura inquirente nella risoluzione di casi di morti sospette ed altri reati accomunati dalla presenza di insetti. Purtroppo in Italia solo da pochi anni si è sviluppato l’interesse verso la materia e ancora oggi gli entomologi forensi non lavorano sistematicamente accanto agli organi di Giustizia. Lo scopo del presente lavoro è una disamina delle potenzialità dell’Entomologia Forense e delle relative applicazioni come strumento spesso determinante per la risoluzione di intriganti e complessi casi giudiziari.

Mosquitoes are men parasitical biters often found by crime scene investigators in the south of Italy. The presence of these species can heavily contribute to the investigators’ efforts. In the past some authors demonstrated the possibility of performing human DNA typing from insect’s gut content for forensic issues. In this paper we report a casework occurred in Sicily: a person was killed in a room where no traces were found apart from a fresh mosquito blood meal stain. Our goal was to obtain a genotypic profile from such a poor and biologically contaminated DNA sample. Human DNA was recovered thanks to an adjusted DNA extraction protocol, allowing the removal of insect-specific molecules. Results showed that it is possible to successfully amplify and to obtain a human-specific 15 loci profile (AmpFLSTR Identifiler – Applied Biosystems), even if DNA is recovered from contaminated traces. Addressing the profile to the major suspect of the murder, we showed that unusual kinds of traces may provide a significant assistance in a real investigation.