RESUMEN

During the investigation of firearm-related incidents, gunshot residues (GSR) can be collected on the scene and individuals (e.g., shooters or bystanders). Their analysis can give valuable information for the reconstruction of the events. Since GSR collection on persons of interest generally occurs a few minutes to hours after discharge, knowledge is needed to understand how organic (O), and inorganic (I) residues are transferred and persist. In this research, the quantities of OGSR and IGSR were assessed on the right and left hands, forearms, face, and nostrils of four shooters. Specimens were collected immediately before the discharge (shooter's blank specimens) and shortly after (30 min) using carbon adhesive stubs. Organic compounds were first extracted from the collection device and analysed using ultra-high-performance liquid chromatography tandem mass spectrometry (UHPLC-MS/MS). Subsequently, IGSR particles were detected on the same stub using scanning electron microscopy coupled with energy-dispersive X-ray spectrometry (SEM/EDS). Shooter's blank specimen analysis revealed background contamination of both O and IGSR in the shooter's environment, predominantly attributed to the presence of an indoor shooting range. However, the background quantities generally remained below the associated 30-minute specimen. Thirty minutes after a discharge, higher quantities were generally detected on the shooter's right and left hands than on other collection regions for both GSR types. Forearms and face emerged as interesting collection alternatives, especially in cases where a person of interest may have washed their hands in the interval between the discharge and collection. In contrast, very low amounts of GSR were detected in the nostrils. Furthermore, the results indicated that OGSR and IGSR have different transfer and persistence mechanisms.

Asunto(s)

Asunto(s)

RESUMEN

Background: The use of radiological approaches in forensic investigations is rapidly emerging as an alternative to traditional autopsies. Here, we present the experience of the Sicilian and Calabrian forensic medical departments over the past five years, highlighting the application of PMCT to support autopsies in cases involving gunshot wound victims. Materials and Methods: From January 2020 to March 2024, thirty cadavers who died from gunshot wounds underwent total body PMCT examinations followed by autopsies. The examinations included multi-planar and 3D reconstructions. Data collected for each subject included gender, age, mode of death, type of weapon, number of shots, body sites affected, and presence of retained bullets. A team of two radiologists and two forensic physicians evaluated the images and compared them with the autopsy findings. Conclusion: PMCT and 3D reconstruction enabled evaluation of entry wounds, fracture margins, injury sites, fragments, and anatomical trajectories. The results from PMCT were compared with autopsy findings in terms of entry wounds, wound channels, foreign bodies, organ and skeletal injuries, and causes of death. PMCT showed concordance with autopsy findings in determining the cause of death in all cases. The speed, non-invasiveness, and ability to manipulate and reconstruct data make PMCT an ideal technique for supporting forensic investigations and autopsies. PMCT is highly reliable for accurately identifying lethal wounds and determining the cause of death. It excels at tracking wound paths, distinguishing entrance and exit wounds, locating retained bullets, and detecting fragmentation and dispersion of ballistic components.

Asunto(s)

RESUMEN

Most firearm related homicides involve the deceased being forensically examined within a day or two, however, there are times when bodies have been examined and the fired components removed several days or weeks after death, when the body is in an active or advanced state of decomposition. In these cases, ballistic investigation has been found to be complicated due to the damage to the bullets, however the extent of this is not yet known. To date, there have been no studies investigating the effect of human decomposition and the subsequent analysis of bullets lodged in the body in an Australian context. Herein, seven fired copper jacketed bullets were manually inserted into three specific tissue types; lungs, abdomen and leg muscle (twenty-one bullets in total), of human donors in both cool and warm conditions at the Australian Facility for Taphonomic Experimental Research (AFTER). Bullets were removed every three days for a period of twenty-one days, and each bullet underwent manual microscopic examinations by firearms examiners across Australia. Results have indicated that the bullets corrode quickly in warm conditions, compared to bullets exposed to decomposition in cooler conditions. The results of this study will inform investigators and pathologists of the need to remove and examine fired bullets from decomposed bodies as soon as possible, especially in warm conditions to provide firearms examiners with the best opportunity to link fired bullets to a common source.

Asunto(s)

Asunto(s)

RESUMEN

The use of ordnance gelatine has been widespread in the field of ballistics as a simulant for soft tissue when assessing ballistic threats. However, the traditional method of preparing ordnance gelatine is time-consuming and requires precision to ensure that the final mold meets the required specifications. Furthermore, temperature control is necessary post-production, and there are limitations on its usage duration. To address these issues, manufacturers have developed pre-mixed, gelatine-like products that are stable at room temperature and require less preparation time. Nonetheless, it is uncertain whether these new products can perform in the same manner as the gold standard of ordnance gelatine. This study used five types of blocks, including ordnance gelatine (10% and 20%), Clear Ballistics (10% and 20%) and Perma-Gel (10%) and subjected them to 9 mm, 0.380 Auto fired from a universal receiver and a 5.56 × 45 mm ammunition fired by a certified firearms instructor. Delta-V and total energy dissipation were measured after each test using data collected from ballistic chronographs placed in front of and behind each block. High-speed video was recorded, and a cut-down analysis conducted. The findings revealed variations in energy dissipation and fissure formation within the block, with greater energy based on fissure formation observed in the ordnance gelatine. Additionally, the high-speed video showed the occurrence of secondary combustions occurring in the premixed gelatines.

Asunto(s)

RESUMEN

Gunshot wound analysis is an important part of medicolegal practice, in both autopsies and examinations of living persons. Well-established and studied simulants exist that exhibit both physical and biomechanical properties of soft-tissues and bones. Current research literature on ballistic wounds focuses on the biomechanical properties of skin simulants. In our extensive experimental study, we tested numerous synthetic and natural materials, regarding their macromorphological bullet impact characteristics, and compared these data with those from real bullet injuries gathered from medicolegal practice. Over thirty varieties of potential skin simulants were shot perpendicularly, and at 45°, at a distance of 10 m and 0.3 m, using full metal jacket (FMJ) projectiles (9 × 19 mm Luger). Simulants included ballistic gelatine at various concentrations, dental silicones with several degrees of hardness, alginates, latex, chamois leather, suture trainers for medical training purposes and various material compound models. In addition to complying to the general requirements for a synthetic simulant, results obtained from dental silicones shore hardness 70 (backed with 20 % by mass gelatine), were especially highly comparable to gunshot entry wounds in skin from real cases. Based on these results, particularly focusing on the macroscopically detectable criteria, we can strongly recommend dental silicone shore hardness 70 as a skin simulant for wound ballistics examinations.

Asunto(s)

RESUMEN

The use of less lethal weapons aims to mitigate civilian casualties caused by firearm use. However, due to numerous cases in which these weapons caused serious injuries, even lethal injuries, both legislation and the forensic field are interested in characterizing and regulating them better. In the forensic field, there is a lack of strong research about injury patterns of these weapons which makes it difficult to identify the type of weapon employed. In this study, the main objective was to characterize the injury pattern produced by the impact of the 9 mm P.A.K. projectile. A porcine model was used. Four different distances were studied: firm contact, 10 cm, 60 cm and 110 cm, using 3 of the more representative anatomical sites: the head, the hind leg and the ribs. The average measurement of the entrance orifice varied according to the anatomical site, being 6.67 mm wide and 6.25 mm long in the thorax, 7.3 mm wide and 8.8 mm long in the hind legs, and 7.62 mm wide and 7.54 mm long in the head. The variation in width and length measurements was not found to be directly related to the shot distance. The gunshot residues had similar characteristics to those of conventional lead projectiles, however there was more unburned powder deposit near the wounds, with a less dense soot and more dense powder tattoo. Depth varied widely regardless of tissue and firing distance, although loss of penetrating power and injury is observed as one moves away from the target.

Asunto(s)

RESUMEN

A smoothbore musket firing a round ball was the primary weapon of the infantry from the 16th to mid 19th century. Musket ball injuries are thus relatively common when archaeological remains of battlefield victims from that period are studied. Several experimental studies have focused on terminal ballistics of a musket ball. In addition, there is a good supply of historical records directly from the battlefield and military hospitals. Studies and historical records have both concluded that head injuries are among the most lethal types of musket ball damage. In this study we utilized modern day research methods, including Synbone ballistic skull phantoms and computed tomography (CT) imaging, to examine more closely the head injuries and tissue damage caused by a musket ball. We were especially interested to observe how different musket ball velocities and shooting distances would influence bone and soft tissue defects. Our experiments clearly demonstrated that musket ball was a lethal projectile even from a longer distance. Already at low velocities, the musket ball perforated through the skull. Velocity also influenced the appearance of entrance and exit wounds. CT imaging provided us with a three-dimensional view of the wound channel, skull fragments and lead remnants inside the skull phantom. According to our findings, musket ball velocity influenced defect size and cavitation. In addition, velocity influenced the size and distribution of skull fragments and lead remnants in the wound channel. Combining all these aspects could aid us in studies of archaeological musket ball victims. In particular, they could help us to estimate the shooting distance and shed light on the potential course of events in the battlefield.

Asunto(s)

RESUMEN

Contact shots to the head often leave behind biological traces inside firearm barrels, a phenomenon of great forensic interest. Until now, the visualization and preservation of these traces presented a significant challenge, lacking a reliable method. This study addresses this gap by searching for a suitable method to extract the traces within a casting. Using alginate or gelatine as suitable materials, the results were hampered by serious adhesion issues and their extraction out of the firearm barrel was impeded. Finally, the combination of 11% gelatine with 1% alginate, introduced into the barrel around a 'central spine', succeeded to consistently produce replicable castings. Experimental contact shots displayed a distinct staining gradient from the muzzle to the rear of the barrel, as revealed through endoscopy and proved in the macroscopic casting. The technique proved effective for various common handgun barrels and successfully preserved blood and gunshot residue (GSR) patterns within the barrel. This method offers the dual benefits of visually mapping staining patterns and securing localized samples for targeted molecular genetic analysis in forensic investigations.

Asunto(s)

RESUMEN

When dealing with badly preserved cadavers or skeletal human remains, the assessment of death circumstances remains challenging. When forensic evidence cannot be taken from the skin and soft tissue, the information may only be deduced from more resistant elements such as bone. Compared to cranial gunshot injuries, reliable data on ballistic long bone trauma remains scarce. This study aims to define ballistic fracture characteristics in human long bones. The shaft of 16 femurs and 13 humeri from body donors was perpendicularly shot with a 9-mm Luger full metal jacket bullet at an impact velocity of 360 m/s from a distance of 2 m. Some bones were embedded in Clear Ballistics Gel®, and some were shot without soft tissue simulant in order to better visualise the fracture propagation on the high-speed camera. The fractures were examined macroscopically and compared between the sample groups. We consistently found comminuted fractures with a stellate pattern. Fracture details were classified into entrance, exit and general characteristics. For some traits, we detected different occurrence values in the group comparison. The results indicate that some of the traits depend on bone properties such as shaft diameter, bone length and cortical thickness. The presence of ballistic gel also influenced some fracture traits, emphasising the relevance of soft tissue simulant in osseous gunshot experiments. This study revealed new insights in the detailed fracture pattern of human long bones. These may serve as guidelines for the identification and reconstruction of gunshot trauma in human long bones.

Asunto(s)

RESUMEN

Human surrogates have long been employed to simulate human behaviour, beginning in the automotive industry and now widely used throughout the safety framework to estimate human injury during and after accidents and impacts. In the specific context of blunt ballistics, various methods have been developed to investigate wound injuries, including tissue simulants such as clays or gelatine ballistic, physical dummies and numerical models. However, all of these surrogate entities must be biofidelic, meaning they must accurately represent the biological properties of the human body. This paper provides an overview of physical and numerical surrogates developed specifically for blunt ballistic impacts, including their properties, use and applications. The focus is on their ability to accurately represent the human body in the context of blunt ballistic impact.

Asunto(s)

RESUMEN

Shots with two different calibres (0.32 Auto and 9 mm Luger) were fired through phantoms that simulated human torsos, mounted on undercarriages with witness panels. The perforated phantoms were scanned with computed tomography (Siemens) using 80 kV and 140 kV and a slice thickness of 1 mm. The intracorporeal trajectories in the phantoms were compared to the known extracorporeal trajectories, derived from the perforations in witness panels. The discrepancy between the intracorporeal and extracorporeal trajectories, denoted as the absolute angle, was calculated for the trajectories before (front) and after (rear) the phantoms. Mean absolute angles at the front were lower than at the rear (2.27° vs. 4.54°) and the difference was statistically significant (p < 0.001). The results of the study imply that the line between the entrance and the exit wound in a scanned victim can be extended to the extracorporeal bullet trajectory leading towards the entrance wound. The absolute angles presented in this study give an impression of the expected errors with the two calibres. This can be helpful in shooting investigations to assess the position of the shooter from entrance and exit wounds in a scanned victim.

Asunto(s)

RESUMEN

Computed tomography (CT) may have a crucial role in the forensic documentation and analysis of firearm injuries. The aim of this forensic ballistics case study was to explore whether two types of expanding bullets and a full metal-jacketed bullet could be differentiated by inspecting bullet fragments and fragmentation pattern in CT. Three types of .30 caliber bullets (full metal-jacketed Norma Jaktmatch, expanding full-copper Norma Ecostrike, and expanding soft-point Norma Oryx) were test fired from a distance of 5 m to blocks of 10% ballistic gelatine. CT scans of the blocks were obtained with clinical equipment and metal artifact reduction. Radiopaque fragments were identified and fragmentation parameters were obtained from the scans (total number of fragments, maximum diameter of the largest fragment, distance between entrance and the closest fragment, length of the fragment cloud, and maximum diameters of the fragment cloud). The fragmentation patterns were additionally visualized by means of 3D reconstruction. In CT, the bullet types differed in several fragmentation parameters. While the expanding full-copper bullet Ecostrike left behind only a single fragment near the end of the bullet channel, the soft-point Oryx had hundreds of fragments deposited throughout the channel. For both expanding bullets Ecostrike and Oryx, the fragments were clearly smaller than those left behind by the full metal-jacketed Jaktmatch. This was surprising as the full metal-jacketed bullet was expected to remain intact. The fragment cloud of Jaktmatch had similar mediolateral and superoinferior diameters to that of Oryx; however, fragments were deposited in the second half of the gelatine block, and not throughout the block. This case study provides a basis and potential methodology for further experiments. The findings are expected to benefit forensic practitioners with limited background information on gunshot injury cases, for example, those that involve several potential firearms or atypical gunshot wounds. The findings may prove beneficial for both human and wildlife forensics.

Asunto(s)

RESUMEN

The article presents the experimental study results of damaged clothes imitators' (coarse calico) features in consequence of shot by ammunitions with hollow-point bullet from a 12-gauge fire smoothbore weapon (12×70). The generation mechanism of coarse calico damage during wound of underlying biological human body's imitator by bullet and the factors influencing on mentioned process have been clarified using high-speed video recording.

Asunto(s)

RESUMEN

OBJECTIVE: To study the morphology of distribution of shot factors on white targets made of coarse calico at different distances. MATERIAL AND METHODS: The study was conducted on 57 experimental damages of targets made of cotton fabric, caused by shots from hunting self-loading Steyr Mannlicher AUG-Z3 carbine of.223 Rem caliber. The number of experimental firings equal 19 was done by 3 shots at the distance from close range to 250 cm. The examination of shot targets was carried out using the visual, metric, stereoscopic (Leica 125M microscope) methods, in ultraviolet rays (LUMATEC SUPERLITE M Series light). RESULTS: The nature and morphology of distribution of gunshot residue on targets' surfaces made it possible to establish close range firing zones. The nature in which soot is deposited during shot under the conditions of point-blank range and in the first zone of close range (up to 8 cm) allows to establish the position of weapon's transverse plane relative to the target basing on a specific blowout of a gas-powder jet from special design of flame arrestor. The performed experimental shooting from hunting self-loading Steyr Mannlicher AUG-Z3 carbine made it possible to determine the metric and morphological characteristics of the close range firing zones: 1 zone is equal a distance up to 8 cm; 2 zone - up to 30 cm; 3 zone - up to 100 cm from muzzle of weapon. The design features of Steyr Mannlicher AUG-Z3 carbine's flame arrestor allow to identify the type of weapon according to the morphological pattern of target's damage. The complex of obtained data makes it possible to determine the firing distance with high accuracy.

Asunto(s)

RESUMEN

The aim of this study is to analyze the injury potential of the free-falling bullet in the cranium, which is known as a tired bullet in the public, with the finite element method (FEM) In the study, as penetrant 9 × 19 mm FMJ bullets with vertical falling angle, adult human skull and brain tissue were discussed. The results of the analysis with the Finite element method, which is similar to the cases reported before, revealed that free-falling bullets as a result of shooting into the air can cause fatal injuries.

Asunto(s)

RESUMEN

The aim of this study was to establish the degree of projectile incidence angle with obstacle on forensic medical characteristic of gunshot injuries arising from smoothbore weapon fire and bullet ricochet. Based on the comprehensive forensic study results of experimental entry gunshot injuries, statistically significant differences in the following morphological signs were found for two ranges of incidence angle values (10-20° and 30-50°): «Number of MD¼, «Length 1 MD¼, «Length 2 MD¼, «Width 1 MD¼, «Orientation of AD to the conventional clock face relative to MD 1 or to the group of largest MD (max. value)¼. The medians and limits of 99% confidence intervals of these features values were observed depending on the range of incidence angle values. The revealed patterns can be used in expert practice during forensic medical examination of gunshot injuries formed as a result of a projectile ricochet after smoothbore weapon fire, as well as to develop a methodology for conducting a forensic study of this gunshot injury type.

Asunto(s)

RESUMEN

Forensic investigations of cranioencephalic ballistic trauma involve several aspects, including the study of terminal ballistics. This includes the analysis of projectiles and the damage they cause. Although some projectiles are considered "non-lethal", serious injuries and deaths secondary to the use of this type of ammunition have been reported. We report the case of a 37-year-old man who died from ballistic head trauma after the use of "Gomm Cogne" ammunition. A post-mortem computed tomography (CT) showed a right temporal bone defect and seven foreign bodies. Three of these were located in the encephalic parenchyma, which showed diffuse hemorrhagic changes. External examination indicated that this was a contact entry wound and confirmed encephalic involvement. This case illustrates the potential lethality of this type of ammunition with CT and autopsy with similar features to single projectile firearm injuries.

Asunto(s)

RESUMEN

The purpose of the scientific work is to outline the main stages of the development of forensic examination of gunshot injuries in Russia. The analysis of the special literature from 1865 to the present time has demonstrated that the issue of forensic examination of gunshot injuries has been analyzed quite deeply by Russian forensic specialists. Meanwhile, expert practice sets forth tasks that are associated with the emergence of new firearm samples and new methods of laboratory and instrumental diagnosis.

Asunto(s)