Post-mortem to ante-mortem facial image comparison for deceased migrant identification.

The identification of deceased migrants is a global challenge that is exacerbated by migration distance, post-mortem conditions, access to ante-mortem data for comparison, inconsistent international procedures and lack of communication between arrival and origin countries. Due to low technology requirements, fast speed analysis and ease of transferring digital data, facial image comparison is particularly beneficial in those contexts, especially in challenging scenarios when this may be the only initial ante-mortem data available to identify the deceased. The Facial Identification Scientific Working Group (FISWG) professional guidelines for facial image comparison were developed for living facial appearance, and, therefore, a tailored protocol for the application of post-mortem to ante-mortem facial image comparison was proposed and evaluated in this research. The protocol was investigated via an inter-observer and an accuracy study, using 29 forensic cases (2001-2020) from the University of Milan, provided by the Laboratory of Forensic Anthropology and Odontology. In order to replicate a migrant identification scenario, each post-mortem subject was compared to all 29 ante-mortem targets (841 comparisons). The protocol guided the practitioner through stages of facial image comparison, from broad (phase 1) to more detailed (phase 3), eventually leading to a decision of 'exclusion' or 'potential match' for each post-mortem to ante-mortem case (phase 4). In phase 4, a support scale was also utilised to indicate the level of confidence in a potential match. Each post-mortem subject could be recorded with multiple potential matches. The protocol proved to be useful guide for facial image comparison, especially for less experienced practitioners and the inter-observer study suggested good reproducibility. The majority (82-96%) of ante-mortem subjects were excluded at the first stage of the protocol, and 71 full post-mortem to ante-mortem facial image comparisons were carried out. On average, two or three potential matches were recorded for each post-mortem subject. The overall accuracy rate was 85%, with the majority (79%) of ante-mortem non-targets correctly excluded from the identification process. An increased number and quality of available ante-mortem images produced more successful matches with higher levels of support. All potential matches involving non-targets received low levels of support, and for 73% of the post-mortem subjects, the ante-mortem target was the only recorded potential match. However, two ante-mortem targets were incorrectly excluded (one at the first stage of the protocol) and therefore changes to the protocol were implemented to mitigate these errors. A full protocol and a practical recording chart for practitioner use is included with this paper.

The rights of migrants to the identification of their dead: an attempt at an identification strategy from Italy.

Europe is turning a blind eye on a humanitarian disaster unfolding at its doorsteps, with thousands of migrants dying unidentified in Mediterranean waters. Since 2014, Italy has been struggling in an almost indifferent international scenario to identify its dead migrants. Despite the lack of sufficient resources, of the difficulties in collecting post mortem data from the disseminated bodies, and of the problems of contacting and collecting ante mortem information from relatives, it has been proven, with a series of pilot studies, that not only can these bodies be identified but that relatives are also looking for their loved ones and need death certificates. This article focuses on the administrative limbo and lack of regulations obliging single states to engage in appropriate procedures to maximise identification.

Improving 3D-3D facial registration methods: potential role of three-dimensional models in personal identification of the living.

Personal identification of the living from video surveillance systems usually involves 2D images. However, the potentiality of three-dimensional facial models in gaining personal identification through 3D-3D comparison still needs to be verified. This study aims at testing the reliability of a protocol for 3D-3D registration of facial models, potentially useful for personal identification. Fifty male subjects aged between 18 and 45 years were randomly chosen from a database of 3D facial models acquired through stereophotogrammetry. For each subject, two acquisitions were available; the 3D models of faces were then registered onto other models belonging to the same and different individuals according to the least point-to-point distance on the entire facial surface, for a total of 50 matches and 50 mismatches. RMS value (root mean square) of point-to-point distance between the two models was then calculated through the VAM® software. Intra- and inter-observer errors were assessed through calculation of relative technical error of measurement (rTEM). Possible statistically significant differences between matches and mismatches were assessed through Mann-Whitney test (p < 0.05). Both for intra- and inter-observer repeatability rTEM was between 2.2 and 5.2%. Average RMS point-to-point distance was 0.50 ± 0.28 mm in matches, 2.62 ± 0.56 mm in mismatches (p < 0.01). An RMS threshold of 1.50 mm could distinguish matches and mismatches in 100% of cases. This study provides an improvement to existing 3D-3D superimposition methods and confirms the great advantages which may derive to personal identification of the living from 3D facial analysis.

Twenty-five years of unidentified bodies: an account from Milano, Italy.

The identification of decedents has always been a central issue in forensic pathology, for ethical, criminal, and administrative reasons, but today, it needs more attention due to issues related not only to migration but also to the weakening of family ties. This article presents a descriptive study discussing the Italian regulatory situation developed in the last decade to face the many identification issues, with all its improvements and flaws. Hence, data gathered in 25 years of at the Institute of Legal Medicine of Milan and the epidemiology of unidentified decedents are illustrated. Briefly, from 1995 to 2019, the number of unidentified human remains with no identity or requesting verification of identity amounts to 726, i.e., 3% circa of all autopsies performed at the Institute, with an average of 29 individuals per year. In total, 528 (72.7%) individuals were successfully identified, 100 (13.8%) remained without an identity, and 98 (13.5%) individuals remained with suspected yet unconfirmed identities. Percentages for each identification technique are displayed, with insight into the role of forensic anthropology and odontology compared to genetics, and into the misuse of non-scientific methods allowed by Public Prosecutors. All the data is compared, as much as possible, with the very few recent studies concerning the problem worldwide. Finally, the article aims to show the Italian experience in dealing with unidentified bodies, in order to provide food for thought for other countries toward a discussion regarding a global issue which is sometimes taken for granted and underestimated.

Common and much less common scenarios in which botany is crucial for forensic pathologist and anthropologists: a series of eight case studies.

It is commonly accepted that crime scene recovery and recording are key moments of any judicial inspection in which investigators must decide on the correct strategies to put into place. Complex outdoor scenarios, presenting partially or entirely skeletonised remains, can benefit more than others by the intervention of environmental specialists (forensic anthropologists, archaeologists, entomologists and botanists). These experts are capable of singling out, correctly recording and recovering environmental evidence that can lead to a more comprehensive reconstruction of a given criminal episode. If human remains are discovered in an outdoor scenario, the on-site presence of a botanist will guarantee a correct approach to the identification, recording and recovery of any botanical evidence. If an on-site botanist is not available, the operators must be capable of both the botanical evaluation of a scene and the implementation of correct botanical sampling protocols.The following collection of unusual case histories that aim at underlining the efficacy of forensic botany will examine the determination of post mortem or the post depositional interval, evidence for a victim's post mortem transfer, evidence for the identification of a primary crime scene and evidence for the identification of a victim's dismemberment site. In another two cases, one, we will illustrate the important role that forensic botany played in the discrimination between botanical material used to voluntarily conceal a victim and vegetation that had grown naturally above a disposal site, whereas the other will highlight the protocols implemented for the identification of a murder weapon.

3D quantitative analysis of early decomposition changes of the human face.

Decomposition of the human body and human face is influenced, among other things, by environmental conditions. The early decomposition changes that modify the appearance of the face may hamper the recognition and identification of the deceased. Quantitative assessment of those changes may provide important information for forensic identification. This report presents a pilot 3D quantitative approach of tracking early decomposition changes of a single cadaver in controlled environmental conditions by summarizing the change with weekly morphological descriptions. The root mean square (RMS) value was used to evaluate the changes of the face after death. The results showed a high correlation (r = 0.863) between the measured RMS and the time since death. RMS values of each scan are presented, as well as the average weekly RMS values. The quantification of decomposition changes could improve the accuracy of antemortem facial approximation and potentially could allow the direct comparisons of antemortem and postmortem 3D scans.

Recognition of children on age-different images: Facial morphology and age-stable features.

The situation of missing children is one of the most emotional social issues worldwide. The search for and identification of missing children is often hampered, among others, by the fact that the facial morphology of long-term missing children changes as they grow. Nowadays, the wide coverage by surveillance systems potentially provides image material for comparisons with images of missing children that may facilitate identification. The aim of study was to identify whether facial features are stable in time and can be utilized for facial recognition by comparing facial images of children at different ages as well as to test the possible use of moles in recognition. The study was divided into two phases (1) morphological classification of facial features using an Anthropological Atlas; (2) algorithm developed in MATLAB® R2014b for assessing the use of moles as age-stable features. The assessment of facial features by Anthropological Atlases showed high mismatch percentages among observers. On average, the mismatch percentages were lower for features describing shape than for those describing size. The nose tip cleft and the chin dimple showed the best agreement between observers regarding both categorization and stability over time. Using the position of moles as a reference point for recognition of the same person on age-different images seems to be a useful method in terms of objectivity and it can be concluded that moles represent age-stable facial features that may be considered for preliminary recognition.

Age- and sex-related growth patterns of the craniofacial complex in European children aged 3-6 years.

BACKGROUND: Craniofacial growth changes in young children are not yet completely understood. Up-to-date references for craniofacial measurements are crucial for clinical assessment of orthodontic anomalies, craniofacial abnormalities and subsequent planning of interventions. AIM: To provide normal reference data and to identify growth patterns for craniofacial dimensions of European boys and girls aged 3-6 years. SUBJECTS AND METHODS: Using standard anthropometric methodology, body weight, body height and 23 craniofacial measurements were acquired for a cross-sectional sample of 681 healthy children (362 boys and 319 girls) aged 3-6 years from Germany, Italy and Lithuania. Descriptive statistics, correlation coefficients, percentage annual changes and percentage growth rates were used to analyse the dataset. RESULTS: Between the ages of 3-6 years, craniofacial measurements showed age- and sex-related patterns independent from patterns observed for body weight and body height. Sex-related differences were observed in the majority of craniofacial measurements. In both sexes, face heights and face depths showed the strongest correlation with age. Growth patterns differed by craniofacial measurement and can be summarised into eight distinct age- and sex-related patterns. CONCLUSION: This study provided reference data and identified sex- and age-related growth patterns of the craniofacial complex of young European children, which may be used for detailed assessment of normal growth in paediatrics, maxillofacial reconstructive surgery and possibly for forensic age assessment.

Temperature measurement from the brain and rectum in charred corpses: a pilot study on an animal model.

Measurement of body temperature provides relevant data on postmortem interval, and different studies have been so far attempted to apply temperature assessment methods also under extreme environmental conditions; however, none of them has been performed yet on charred or heated bodies, where temperature measurement is presumed to be unreliable because of the possible influence of heating. This study aimed at verifying any possible early-stage alterations of rectal and endocranial temperature due to fire on an animal model during the charring process. Three pigs, 2 adults (pigs 1 and 2) whose weight was about 50 kg each and 1 piglet weighing 3 kg, were heated and burnt on a natural fire lit on top of a wooden stack, without the use of accelerants; 2 thermocouples were positioned in the rectum and in the cranium to record second-by-second rectal and endocranial temperature values. Results demonstrate that the rectal temperature does not seem to increase in adult pigs for 40 to 50 minutes after the body has been exposed to fire, probably because of the thermal insulating characteristics of the adipose tissue. Therefore, temperature may still be of some help for estimating postmortem interval on heated or burnt cadavers.

Autopsy doesn't always tell all: The importance of exhuming skeletal remains of cemetery unidentified decedents.

The process of personal identification differs according to the state of preservation of the corpse, becoming more complicated when dealing with remains altered by taphonomic variables. Since 2015, the staff of the Laboratory of Forensic Anthropology and Odontology (LABANOF) of the University of Milan has been engaged in recovering the skeletons of 36 unknown people from the cemeteries of the city of Milan, to redraw their biological profiles and give them back the possibility of being identified. Of the 36 starting skeletons, 7 have been identified and therefore are not the object of this study, 25 individuals were previously subjected to an autopsy examination and 4 skeletons were studied for the first time in the present work. The post-mortem data of all the individuals who had previously undergone autopsy and had not yet been identified (n = 25) have been retrieved from the archives of the Institute of Forensic Medicine in Milan and allowed for a comparison with those obtained from the new anthropological study of each exhumed skeleton. The authors aim to present the three most interesting cases to better highlight the results that emerged from the comparison. The autopsy information alone lacked important details. In all cases, the anthropological examination proved to be capable of detailing the biological profile of the unknowns even after a long period of inhumation (even more than 20 years). The limitations of instrumental investigations in achieving the goal single-handedly and the importance of recovering the unknown skeletons from cemeteries for identification purposes are discussed.

The importance of an anthropological scene of crime investigation in the case of burnt remains in vehicles: 3 case studies.

Inspection of a crime scene is a crucial step in forensic medicine, and even the methods taught by forensic anthropology are essential. Whereas a thorough inspection can provide crucial information, an approximate inspection can be useless or even harmful. This study reports 3 cases of burnt bodies found inside vehicles between 2006 and 2009 in the outskirts of Milan (Italy). In all 3 cases, the victim was killed by gunshot, and the body was burnt in the vehicle to destroy signs of skeletal injury and prevent identification. In every case, the assistance of forensic anthropologists was requested, but only after the inspection of the body at autopsy showed that the remains were incomplete, thus making it more difficult to determine the identity, cause, and manner of death. A second scene of crime inspection was therefore performed with strict anthropological and adapted archeological methods by forensic anthropologists to perform a more complete recovery, proving how much material had been left behind. These cases clearly show the importance of a proper recovery and of the application of forensic anthropology methods on badly charred bodies and the importance of recovering every fragment of bone: even the smallest fragment can provide essential information. Thus, a precise coordination, a correct and thorough recovery of bone fragments, and an anthropological approach are crucial for many issues: analysis of the scene of crime, reconstruction of the corpse, and reconstruction of the perimortem events.

Can facial proportions taken from images be of use for ageing in cases of suspected child pornography? A pilot study.

The age of the victim plays a crucial role for the legal implications concerning pornography. Judges therefore often call on forensic experts to verify the age of individuals depicted on photographs or videos. However, there is no scientifically established protocol available for forensic practice in such cases. The conventional methods such as the evaluation of secondary sexual characteristics provide unsatisfactory results particularly when the legally relevant ages for child pornography (i.e. 14 and 18 years) are concerned. To overcome these limits, a European research group has explored the applicability of facial proportions as an age indicator on images. In this pilot study, standardized facial images of 353 females and 20 males from four age groups (6, 10, 14 and 18 years) were randomly selected for the metric analysis from a large data set including German, Italian and Lithuanian subjects. In this sample, several indices extracted from the frontal and lateral photographs were closely correlated to their respective indices taken from the living individuals. Furthermore, age-related changes were identified for indices taken from the photographs. The discriminant analysis showed that for the pooled sample, 60.3% of the cases were correctly classified into the respective age group. The percentage of correctly classified cases increased in the respective country samples as follows: 69.9% for Germany, 69.4% for Lithuania and 80.5% for Italy. The present study suggests that the metric assessment of the face may be used for age estimation on images. Nonetheless, more work needs to be done in order to verify the reliability of these findings on a large sample.

3D-3D facial registration method applied to personal identification: Does it work with limited portions of faces? An experiment in ideal conditions.

Personal identification of faces represents a challenging issue, especially for what concerns the quantification of the comparison. The 3D-3D superimposition approach proved to distinguish between matches and mismatches. However, the potential of this procedure applied to cases where only parts of faces are visible still has to be verified. This study aimed at verifying the applicability of a 3D-3D procedure to faces divided into three thirds. 3D models of fifty male subjects acquired through stereophotogrammetry were used. The 3D facial models were divided into upper, middle, and lower thirds and registered onto other models belonging to the same and different individuals according to the least point-to-point distance. In total, 50 matches and 50 mismatches were analyzed. RMS value (root mean square) of point-to-point distance between the two facial surfaces was calculated through VAM® software. Statistically significant differences between matches and mismatches in each facial third were assessed through Mann-Whitney test (p < 0.05). On average, RMS value in matches was 0.32 ± 0.12 mm in upper third, 0.36 ± 0.15 mm in middle third, and 0.40 ± 0.20 mm in lower third, respectively; in mismatches, RMS value was 1.40 ± 0.32 mm in upper third, 1.96 ± 0.58 mm in middle third, and 2.39 ± 0.90 mm in lower third, respectively. Differences in RMS values between matches and mismatches were significantly different for all facial thirds, without superimpositions (p < 0.01). This study shows that the existing 3D-3D superimposition methods may be useful also when only a limited portion of face is visible in ideal conditions. Their application to forensic cases of identification still needs to be verified.

A Pilot COVID-19 Surveillance Program at the Zendrini Center in Milan (Italy) for Unaccompanied Foreign Minors.

During the COVID-19 pandemic, not only crowded refugee camps and immigration detention centers, but also receptions were places in which outbreaks occurred. To date there has been no report of the application of a COVID-19 surveillance system in reception centers for unaccompanied foreign minors only, who most of all deserve the utmost attention. Aware of this critical issue, we implemented a pilot COVID-19 surveillance program at the Zendrini center in Milan. It was started in September 2021 and was carried out for 4 months. Nasopharyngeal antigenic swabs were adopted. One day a week, two forensic physicians performed the first antigenic swab to minors who had just entered the center, or a monitoring swab after 15 days to those who were still hosted at the center. Operators were also swabbed for surveillance. A total of 80 subjects were enrolled and divided into 68 (72.5%) unaccompanied foreign minors and 22 (27.5%) operators. A total of 178 antigenic nasopharyngeal swabs were performed and tested negative. Regarding the monitoring activities, it was found that the minimum number of swabs per subject was 1 and the maximum number was 7, with an average value of 2.2 per individual. Having been able to confirm the absence of SARS-CoV-2 within the community represented a way to protect individual and collective health that could not have been pursued otherwise. Only inclusive approaches can allow communities and societies to respond more effectively to this crisis, and reduce the risk of future ones, intended as both upcoming COVID-19 waves and new infectious diseases.

A new atlas for the evaluation of facial features: advantages, limits, and applicability.

Methods for the verification of the identity of offenders in cases involving video-surveillance images in criminal investigation events are currently under scrutiny by several forensic experts around the globe. The anthroposcopic, or morphological, approach based on facial features is the most frequently used by international forensic experts. However, a specific set of applicable features has not yet been agreed on by the experts. Furthermore, population frequencies of such features have not been recorded, and only few validation tests have been published. To combat and prevent crime in Europe, the European Commission funded an extensive research project dedicated to the optimization of methods for facial identification of persons on photographs. Within this research project, standardized photographs of 900 males between 20 and 31 years of age from Germany, Italy, and Lithuania were acquired. Based on these photographs, 43 facial features were described and evaluated in detail. These efforts led to the development of a new model of a morphologic atlas, called DMV atlas ("Düsseldorf Milan Vilnius," from the participating cities). This study is the first attempt at verifying the feasibility of this atlas as a preliminary step to personal identification by exploring the intra- and interobserver error. The analysis yielded mismatch percentages from 19% to 39%, which reflect the subjectivity of the approach and suggest caution in verifying personal identity only from the classification of facial features. Nonetheless, the use of the atlas leads to a significant improvement of consistency in the evaluation.

Detection of blunt, sharp force and gunshot lesions on burnt remains: a cautionary note.

The study of skin and bone lesions may give information concerning type and manner of production, but in burnt material modification of tissues by the high temperatures may considerably change the morphological characteristics of the lesions. This study aims at pointing out the effects of burning head of pigs with several types of lesions (blunt trauma, sharp force, and gunshot lesions) on soft tissues and bones, both from a morphological and chemical point of view. Results show that the charring process does not completely destroy signs of lesions on bones, which can often be recovered by cleaning bone surface from charred soft-tissue residues. Furthermore, neutron activation analysis test proved that antimony may be detectable also on gunshot entry wounds at the final stages of charring process.

Scene-of-crime analysis by a 3-dimensional optical digitizer: a useful perspective for forensic science.

Analysis and detailed registration of the crime scene are of the utmost importance during investigations. However, this phase of activity is often affected by the risk of loss of evidence due to the limits of traditional scene of crime registration methods (ie, photos and videos). This technical note shows the utility of the application of a 3-dimensional optical digitizer on different crime scenes. This study aims in fact at verifying the importance and feasibility of contactless 3-dimensional reconstruction and modeling by optical digitization to achieve an optimal registration of the crime scene.

Look before washing and cleaning: A caveat to pathologists and anthropologists.

Partially or totally skeletonized bodies are undoubtedly the most challenging scenario to deal with for forensic pathologists and anthropologists. Indeed, in such cases, being able to figure out the cause and manner of death is often tricky. Human remains require to be washed and cleaned before a thorough assessment of any signs of trauma. However, bones and any fragment of more or less putrefied soft tissues may be home to crucial traces for investigative purposes. They are often located in the context of apparently meaningless dirt and, sometimes they are even invisible to the naked eye. Therefore, their careless cleaning inevitably leads to an unintentional loss of such traces with a negative impact on subsequent investigations. For these reasons before proceeding with cleaning, exhaustive examination and sampling must be carried out. In particular fragments of soft tissues, even if putrefied, are absolutely not to be considered as a hindrance for forensic purposes, since they could still provide valuable information after histological examination. Finally, forward-thinking professionals should think about the possible presence of exogenous micro-traces of forensic concern and collect specimens to be analyzed through in-depth analyses, such as Scanning Electron Microscopy with Energy Dispersive X-ray Spectrometry (SEM/EDX). The present series of cases demonstrates that crucial forensic information can be obtained through the analysis of apparently meaningless residues and even of micro-traces not visible to the naked eye and mixed with trivial dirt.

The detection of microscopic markers of hemorrhaging and wound age on dry bone: a pilot study.

An example of the barriers and conceptual differences between forensic anthropology and pathology can be seen in determining the vitality of a wound. Pathology can make use of skin color and microscopic techniques; anthropology (as concerns the study of dry bone) needs different criteria. The diagnosis of the vitality of a wound (whether it is produced antemortem or postmortem) as well as determination of the time elapsed between the production of the wound and death is a crucial issue in forensic pathology. In fresh skin, the red-purplish coloration of a cut or bruise will reveal its vitality, whereas the change in coloration, from a macroscopic perspective, will reveal the time of survival. In more difficult cases, microscopic analyses can be performed. Bone follows similar "laws" as concerns the evolution of the histologic picture, but even if the beginning of healing processes (periosteal bone production and callus formation) can be detected macroscopically and radiologically, these processes require a long time.The scope of this pilot study was therefore to collect bone fractures from cadavers with a known time of survival, have them undergo a simulated putrefaction procedure until they became "dry or macerated bone" and perform macroscopic and microscopic analysis to verify the potential of histology in identifying "vital" processes in putrefied soft-tissue-free bone.A total of 6 samples of fractured bone (cranium, rib, and tibia) were taken from cadavers with known time of survival between trauma and death. Time intervals ranged from a few seconds after the bone fracture had been inflicted, to several hours, days, and weeks. A negative control was included (postmortem fracture). The bone was decalcified and stained with hematoxylin and eosin, Perls' (for the demonstration of hemosiderin deposits), Periodic Acid Schiff, phosphotungstic acid-hematoxylin, and Weigert (for the demonstration of fibrin). Immunohistochemistry was performed using a monoclonal antibody antihuman Glycophorin A.Results show the presence of clots and red blood cell residues on the fractured margins, strongly indicative of vital reaction.This study, though certainly not conclusive, shows that it may be worth pursuing the study of bone fractures from a histopathological point of view even on "dry bone" to verify whether the fracture is vital or not, and, if so, if its time of production can be verified.

Three-dimensional facial anatomy evaluation: Reliability of laser scanner consecutive scans procedure in comparison with stereophotogrammetry.

Laser scanner devices are acquiring a growing importance in facial anatomy. Most studies have analysed facial scans obtained through two simultaneous captures, whereas the same result can be obtained by consecutive three-dimensional (3D) scans. However, this latter procedure has not yet been validated. Fourteen volunteers underwent face image capture through stereophotogrammetry (VECTRA M3) and three consecutive facial scans through a laser scanner (Konica Minolta Vi910). The concordance between 14 linear distances, 12 angles, facial surface area and volume measurements was verified by the Bland-Altman test and calculation of absolute and relative technical errors of measurement (TEM/rTEM). The two facial images obtained by the different devices were then registered to calculate point-to-point distance. Most of linear distances and angles showed a high agreement, with "very good" or "good" rTEMs, ranging between 1.1% and 6.4%. Surface area measurements agreed well between the devices (rTEM: 6.3%), while volumes were poorly comparable (rTEM: 25.8%); the root mean square point-to-point distance was 0.80 mm (SD: 0.41). This study first tested the concordance of measurements on facial images obtained by stereophotogrammetry and consecutive laser scans. Results highlight the reliability of linear distances, angles and surface areas measurements, but discourage volume assessment and registration of surfaces acquired through different devices.