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Insects found at a crime scene can produce traces referred to as fly artifacts (FA) due to their movement over the corpse and the manner in which they feed upon it. These can be detrimental for carrying out criminal investigations. Confusing a FA with a genuine bloodspot can lead to misinterpretations, also taking into consideration that FA may contain a human DNA profile. The aim of the present study was to employ scanning electron microscopy (SEM) for the analysis of FA produced by Calliphora vomitoria on hard surfaces and fabrics that are commonly present at crime scenes. FA and control bloodstains were produced under experimental conditions on metal, glass, plaster, cotton, and polyester. After macroscopic analysis, FA were examined at standard low (20–40 ×), medium low (300–600 ×), and high ultrastructural (1200 ×) magnification through a SEM Stereoscan 360, Leica, Cambridge. SEM analysis enabled the identification of distinctive features of FA on hard surfaces, namely, amorphous crystals, micro-crystals with a morphology similar to those of uric or micro-crystals with a comparable morphology to cholesterol, absent in controls. Moreover, red blood cells (RBC) were absent in FA but were always present in controls. On cotton, for both FA and controls, the drop was almost completely absorbed and thus indistinguishable from the underlying fabric texture. On polyester, FA showed amorphous/crystal-like deposits and no RBC, as observed on hard surfaces, except for those showing a completely flat surface. SEM analysis appeared to be suitable for differential diagnosis between FA and genuine bloodstains on hard surfaces, although the results may be inconclusive on tested fabrics.

The reconstruction of dynamic of traffic injuries remains a challenge in forensic pathology and is often based on circumstantial data. Dash Cams are digital video recorders which can be located inside a vehicle and continuously record the view through the windscreen, thus providing objective evidence. Here we present the case of a traffic crash in which a pedestrian was hit by an articulated lorry. The analysis of a video recorded from a Dash Cam retrieved inside the vehicle during the death scene investigation (DSI) was crucial in the reconstruction of the manner of death. Indeed, the death, which was initially assumed to be accidental, was finally deemed as a suicide on the basis of the video recording, which showed an intentional and sudden rush of the victim to the middle of the roadway. Advantages and disadvantages of the use of Dash Cams will be discussed, focusing on the profound differences in the related national and international regulations. Based on the present case, in traffic crashes, the search for Dash Cams during the DSI may be recommended and the video recordings should be analyzed in the setting of a multidisciplinary and multimodal evaluation of the case, for a proper reconstruction of the facts. Supplementary Information The online version contains supplementary material available at 10.1007/s12024-021-00382-0.

The combined event of a suicide and the killing of a pet has been hardly explored in forensic literature, but it is not rare at all. In the reported case the dead corpse of a 60-year old mentally ill woman and the carcass of a dog were found on the bed of a private apartment. In light of death scene investigation, necroscopic examination and toxicological analyses death was attributed to licit drug intoxication and self-strangulation after lethal poisoning of the dog. Due to the presence of two lethal means (cervical noose and drugs), acting in chronological order, the event was classified as a secondary complex suicide. Moreover, the woman, although mentally ill, was a psychiatrist. Thus, her professional background, namely the easy access to psychiatric drugs together with her knowledge of drug composition and properties lead to suppose an occupation related suicide. The comprehensive analysis of all the available information, including death scene investigation, occupational, necroscopic and toxicological data, resulted of the utmost importance for a proper reconstruction of the events and are recommended in complex cases such as occupation related planned complex suicides combined to the killing of pets.

Purpose The decomposition process of human bodies in marine environment is not well understood, and it is influenced by external variables related to the geographical area where the body is submerged. We report the application of two decomposition scores, the Heaton’s score and the van Daalen’s score, on a casuistry of human bodies recovered from the Northern Adriatic Sea. The aims of this study are to verify whether the marine environment of a Mediterranean climate area may affect the applicability of both scores and to develop a prediction model that can be applied on bodies recovered in salt water. Methods A retrospective study was performed on 61 human bodies recovered between 2005 and 2019 from coastal water of the Northern Adriatic Sea nearby the Italian regions Emilia-Romagna and Marche. For each of the 61 cases included, the Total Aquatic Decomposition Score (TADS) was calculated with the Heaton’s score and the Van Daalen’s score. The prediction model was assessed through multiple regression analyses, and the determination coefficients (r2) between TADS and PMSI (expressed in days) and between TADS and Accumulate Degrees Days (ADD) were studied. The prediction model was applied to the entire case sample, to bodies recovered during the warm season and to bodies recovered during the cold season. Results All bodies were recovered floating, and a very poor scavenging activity was observed. The regression analyses showed a strong correlation between the TADS and the total case sample using both scores and both independent variables (PMSI and ADD). The determination coefficients were greater than 0.95 also when considering the total case sample. Discussion The proposed prediction models are not significantly influenced by seasonality, contrarily to what observed on bodies recovered in fresh water in the same climate area. However, the ADD model, which also consider the water temperature, should be preferred for higher decomposition stages. This study helps increase the accuracy of PMSI estimation in bodies recovered from a marine environment of the Northern Adriatic Sea.

Introduction Among the several techniques proposed for the estimation of the Post Mortem Interval (PMI), the analysis of odorous amines has been applied in the past, with conflicting results. The aims of this study are: (i) to develop and validate a GC–MS method for the determination of putrescine (PUT) and cadaverine (CAD) in the human brain (validation study) and (ii) to study the relation of PUT and CAD concentration in the human brain and the PMI (decomposition study). Materials and methods Validation study. Analysis has been performed through GC–MS after a liquid-liquid extraction and a single step-derivatization for the identification and quantification of odorous amines in brain cortex samples. The standard protocol used in forensic toxicology, slightly modified for endogenous compounds according to recent guidelines, was used for validation. Decomposition study. Three uninjured human brains were sampled during the autopsy of three fatal traumatic cases. Along a 120-hour period of decomposition under experimental conditions, each brain was sampled along predetermined time intervals. Results Validation study. Both PUT and CAD validation parameters were within the acceptable values defined by the Scientific Working Group for Forensic Toxicology (SWGTOX), with better selectivity, linearity, accuracy and precision values for PUT. Decomposition study. A significant relationship between PUT and CAD levels and PMI has been demonstrated through statistical analysis with a correlation coefficient of 0.98 for PUT and 0.93 for CAD (p Conclusion Although further experimental studies on a wider number of samples are necessary, the results of this study suggest a possible role of polyamine levels in brain cortex for the estimation of PMI.