Does the Prior Application of the Field Kit Bullet Hole Testing Kit 3 on a Suspected Bullet Hole Bias the Analysis of Atomic Absorption Spectrophotometry?

Forensic ballistics is the study of bullet trajectory and consists of determining gunshot residue (GSR) to identify bullet holes. Among several highly sensitive methods, atomic absorption spectrophotometry (AAS) is employed to analyze GSR in the laboratory. However, it is sometimes necessary to identify bullet holes immediately at a crime scene. The purpose of this examination was to determine whether the use of the field test Bullet Hole Testing Kit 3 (BTK3) on a suspected bullet hole would influence the outcome of AAS‐analysis: Three commonly encountered firearms (Glock17, Tokarev, and Colt) were fired at skin, wood, and cloth. AAS‐analysis was performed with and without previous BTK3 application. The results clearly indicate that there is no significant interaction on the grounds of BTK3 use (BTK3 vs. no‐BTK3 [kit_nokit] [Pb: p = 0.1309; Sb: p = 0.9111], material*kit_nokit [Pb: p = 0.5960; Sb: p = 0.9930], distance*kit_nokit [Pb: p = 0.4014; Sb: p = 0.9184], and firearm type*kit_nokit [Pb: p = 0.9662; Sb: p = 0.9885]); hence, applying this field kit does not falsify later AAS outcomes.     

Radiodense bullet wipe around osseous entrance gunshot wounds

“Bullet wipe” is the material deposited by a bullet on any surface with which it comes into contact after it is fired and may contain debris from the gun barrel, including particles of primer and metal fragments from previously fired bullets. X‐ray analysis is a non‐destructive method by which traces of metallic elements can be visually detected. The analysis of osseous defects for radiodense bullet wipe (RBW) assists in determining the presence or absence of perforating gunshot wounds, especially in fragmented, skeletonized remains. The aim of our current study was to determine the frequency of RBW around entrance firearms injuries that perforated bone. We prospectively analyzed entrance gunshot wounds for RBW over a three‐year period using digital X‐ray analysis (n = 59). We retrospectively reviewed the corresponding autopsy reports to determine the frequency of RBW by biologic sex, reported ancestry, age‐at‐death, location of wound, manner of death, range of fire, bullet caliber, and presence of bullet jacket. Data were analyzed by Fisher's exact test or Chi‐square test with significance levels accepted at p < 0.05. RBW was present in 66% (n = 39) of examined cases. Decedent characteristics did not significantly alter RBW distribution, including biologic sex (p = 0.75), reported ancestry (p = 0.49), and age‐at‐death (p = 0.43). Additionally, the location of the osseous entrance gunshot wound, manner of death, range of fire, and cartridge caliber did not affect RBW detection. All cases involving non‐jacketed rounds (n = 5) showed RBW (p = 0.30). To our knowledge, this study is the first to report the frequency of RBW detection from osseous entrance gunshot wounds.     

Detection of Gunshot Primer Residue on Bone in an Experimental Setting—An Unexpected Finding*

Abstract: Pork ribs with intact muscle tissue were used in an experimental attempt to identify bullet wipe on bone at distances from 1 to 6 feet with 0.45 caliber, full metal jacket ammunition. This resulted in the unexpected finding of primer‐derived gunshot residue (GSR) deep within the wound tract. Of significance is the fact that the GSR was deposited on the bone, under the periosteum, after the bullet passed through a Ziploc^® bag and c. 1 inch of muscle tissue. It is also important to note that the GSR persisted on the bone after the periosteum was forcibly removed. The presence of primer‐derived GSR on bone provides the potential to differentiate gunshot trauma from blunt trauma when the bone presents an atypical gunshot wound. In this study, the presence of gunshot primer residue at a distance of 6 feet demonstrates the potential for establishing maximum gun‐to‐target distance for remote shootings.     

Effects of kinetic energy and firearm-to-target distance on fracture behavior in flat bones

This research implements a fractographic approach to investigate the relationships between kinetic energy, firearm-to-target distance, and various aspects of fracture behavior in gunshot trauma. Gunshot experiments were performed on pig scapulae (n = 30) using three firearms generating different muzzle (initial) kinetic energies, including a 0.32 pistol (103 J), 0.40 pistol (492 J), and 0.308 rifle (2275 J). Specimens were shot from two distances: 10 cm (n = 15) and 110 cm (n = 15). Features evaluated in fractographic analysis such as cone cracks, radiating cracks, crack branching points, and circumferential cracks could be easily identified and measured in flat bones and allowed for statistical comparison of crack propagation behavior under different impact conditions. Higher-energy bullets produced more radiating cracks, more crack branching points, and longer fracture lengths than lower-energy bullets. Distance had no significant effect on fracture morphology at the distances tested. That quantitative measures of crack propagation varied with energy affirms that kinetic energy transfer is important in determining the nature and extent of fracture in gunshot wounds and suggests it may be possible to infer relatively high- versus relatively low-energy transfer using these features. Ranges obtained with the three firearms exhibited considerable overlap, however, indicating that other variables such as bullet caliber, mass, and construction influence the efficiency of energy transfer from bullet to bone. Therefore, fracture morphology cannot be used to identify a specific firearm or to directly reconstruct the muzzle (initial) kinetic energy in forensic cases.     

Utilization of X‐ray Computed Tomography for the Exclusion of a Specific Caliber and Bullet Type in a Living Shooting Victim

A bystander claimed to have been shot by a police officer, and CT scans were used to match qualitative and quantitative aspects of the unremoved bullet with police issued 9 mm Luger ammunition. CT scan methodology proved a valid approach for the measurement of bullets based on calculated measurement capability and correlation with “gold standard” physical measurement by vernier caliper. Measurements regarding length and base diameter, as well as length/diameter ratio, were insufficient to unambiguously identify a specific caliber, or a bullet of specific mass within a caliber class. It was, however, possible to exclude a bullet of specific design and mass with well‐characterized precision and accuracy values under selected CT scan conditions. A 9 mm Luger bullet (115 gr FMJ RN) was excluded from involvement in a shooting based on qualitative bullet shape combined with length, base, and ratio measurements of the bullet in‐situ for the victim.     

Causes of Sudden Death in Patients with Obstructive Sleep Apnea

There are few autopsy studies of patients dying suddenly with obstructive sleep apnea (OSA). Twenty‐five forensic autopsies of unexpected sudden death in individuals with OSA were reviewed. The causes of death were as follows: cardiomyopathy (n = 11); sudden unexpected death without morphologic findings (SUDNA, n = 6); and other cardiovascular diseases not related to OSA (n = 8). The cardiomyopathy group comprised five hearts with concentric left ventricular hypertrophy without dilatation and six with left ventricular diameter >4 cm (dilated cardiomyopathy). Four of six hearts in the SUDNA group showed right ventricular dilatation compared with seven of 11 showed cardiomyopathy and one of eight miscellaneous. The degree of obesity was greatest in the dilated cardiomyopathy group (10 of 11 obese) followed by the SUDNA group (four of six obese). The cardiac findings in patients dying suddenly and unexpectedly with OSA include nonspecific cardiomyopathy, other cardiac conditions, and hearts without a morphologic cause of death, which show frequent right ventricular dilatation as the only finding.     

An Impact Velocity Device Design for Blood Spatter Pattern Generation with Considerations for High‐Speed Video Analysis,

A mechanical device that uses gravitational and spring compression forces to create spatter patterns of known impact velocities is presented and discussed. The custom‐made device uses either two or four springs (k₁ = 267.8 N/m, k₂ = 535.5 N/m) in parallel to create seventeen reproducible impact velocities between 2.1 and 4.0 m/s. The impactor is held at several known spring extensions using an electromagnet. Trigger inputs to the high‐speed video camera allow the user to control the magnet's release while capturing video footage simultaneously. A polycarbonate base is used to allow for simultaneous monitoring of the side and bottom views of the impact event. Twenty‐four patterns were created across the impact velocity range and analyzed using HemoSpat. Area of origin estimations fell within an acceptable range (ΔX_av = ?5.5 ± 1.9 cm, ΔY_av = ?2.6 ± 2.8 cm, ΔZ_av = +5.5 ± 3.8 cm), supporting distribution analysis for the use in research or bloodstain pattern training. This work provides a framework for those interested in developing a robust impact device.     

Recidivism and Psychiatric Symptom Outcomes in a Juvenile Mental Health Court

Few researchers have examined outcomes in Juvenile Mental Health Courts. Recidivism rates were assessed among 108 predominantly African American (95.3%) youth. Ages ranged from 12 to 18 (M = 15.85, SD = 1.45). Substantially fewer re‐convictions, along with re‐arrests, were exhibited among the treatment group (n = 54) compared to the control group (n = 54) after one year of participation or probation supervision. Psychiatric symptomatology among 21 youth was assessed pre‐ and post‐ intervention using the Comprehensive Behavior Rating Scales‐Self Report. Cohen's d effect sizes indicated substantial reductions in mental health symptoms (.33 ≥ d ≤ .88). Results are consistent with the previous studies of problem‐solving court efficacy.     

The Etiology of Basal Vacuolizations in Renal Tubular Epithelial Cells Evaluated in an Isolated Perfused Kidney Model

To determine whether basal lipid vacuolization characteristic of ketoacidosis could be induced with short‐term hypertriglyceridemia, adult Sprague Dawley rat kidneys were perfused in an isolated perfused kidney model with, and without, 11.3 mM (10 g/L) of triglycerides in Krebs‐Henseleit buffer, for 1 and 2 h (n = 5/group). Additional treatments included perfusion with triglycerides with 20 mM of β‐hydroxybutyrate and 2 mM of acetoacetate (n = 5) and perfusion with triglycerides with 70 mM of glucose (n = 1). Basal vacuolization was produced in all groups, but differed in morphology to that reported in postmortem studies. There was no further increase in vacuolization after 2 h of perfusion compared to 1 h (p = 0.24), and the addition of ketones did not alter the morphology or extent of vacuolization. This study using an ex vivo model has confirmed that isolated hypertriglyceridemia is sufficient to cause basal lipid vacuolization in renal tubular epithelial cells, but with different morphology to vacuoles observed in lethal ketoacidosis at autopsy.     

Evaluation of the ADViSOR project: Cross‐situational behaviour monitoring of high‐risk offenders in prison and the community

Purpose. The release on licence of prisoners who have committed serious violent and/or sexual offences requires rigorous risk assessment and risk management. This study evaluates the ADViSOR project, designed to examine the contribution of prison behaviour monitoring to community supervision of a sample of the highest risk offenders released in England and Wales under Multi‐Agency Public Protection Arrangements (MAPPA). Method. The offence‐related behaviour of a total group (n= 25) of MAPPA prisoners in one prison, due for release in the following year to two adjacent probation trust areas, was monitored. Their behaviours in the community were followed up for 1 year. A comparison group (n= 36) was formed of the total number of MAPPA prisoners released from prisons nationally to the same two probation trusts. Results. The frequencies of ADViSOR negative behaviours in prison and the community were strongly correlated, r_s (25) = .55, p= .004, as were positive behaviours, r_s (25) = .56, p= .004. No statistically significant correlations were found either under usual MAPPA processes in the ADViSOR prison or comparison group prisons. The frequency of ADViSOR negative behaviours statistically significantly predicted, with 92% accuracy, the offenders who would reoffend or be recalled to prison (n= 8). Statistically significant similarities in types of behaviour were also identified. Conclusion. Results are discussed in terms of the contribution of behavioural monitoring to risk prediction with high‐risk offenders, consistency of cross‐situational behaviours, and implications for policy and practice.     

The Accuracy and Repeatability of Reconstructing Single Bullet Impacts Using the 2D Ellipse Method

When a bullet punctures a surface, it leaves behind a bullet impact, which can be analyzed in order to determine the origin and trajectory path from which a bullet was discharged using many different scientific methods to reconstruct a shooting scene. The purpose of the research was to test the accuracy and repeatability of reconstructing the impact angle of single bullet impacts using the ellipse method. The research was conducted by firing various calibers of ammunition into drywall panels positioned at varying angles of incidence from 88° until ricochet occurred. This was done in order to determine which caliber type and angle of incidence are most accurate and precise for reconstructing a shooting scene. The study examined four caliber types fired into drywall panels, with 5 repeated shots for each of the 11 angles of incidence (n = 220). Furthermore, 31 participants partook in the study to estimate a bullet impact angle of incidence utilizing the ellipse method. The results show that the best performance (accuracy and repeatability) is seen with the measurements of the 0.45 caliber ammunition. When angle of incidences is low (<64°), the performance (accuracy and repeatability) was seen to be better in all caliber ammunitions. Overall, the data provided for single bullet impacts deposited in drywall show that the ellipse method is useful in providing measurements for most crime scene reconstruction purposes and has also demonstrated that results vary depending on the type of ammunition, firearm, and angle of incidence being examined.     

Temperature‐Dependent Postmortem Changes in Human Cardiac Troponin‐T (cTnT): An Approach in Estimation of Time Since Death

Estimation of time of death is an indispensible requirement of every medico‐legal autopsy, but unfortunately, there is not a single method by which it could be determined accurately. This study focused on the temperature‐dependent postmortem degradation of cardiac troponin‐T and its association with postmortem interval (PMI) in human. The analysis involved extraction of the protein, separation by denaturing gel electrophoresis (SDS‐PAGE), and visualization by Western blot using cTnT‐specific monoclonal antibodies. The area of the bands within a lane was quantified by scanning and digitizing the image using Gel Doc (Universal Hood). The results indicate a characteristic banding pattern among human cadavers (n = 6) and a pseudo‐linear relationship between percentage of cTnT degradation and the log of the time since death (r > 0.95), which can be used to estimate the postmortem interval. The data presented demonstrate that this technique can provide an extended time range during which PMI can be more accurately estimated.     

Forces Required for a Knife to Penetrate a Variety of Clothing Types

In stabbing incidents, it is usual for the victim to be clothed and therefore a knife penetrates both clothes and skin. Clothes (other than leather) have been thought to make little difference to the penetration force. However, there is little quantitative data in the literature. In this study, a range of clothes have been tested, either singly or in layers of, for example, T‐shirt and shirt, to quantify the additional force required when clothes are present. A materials testing system has been used to test the penetration force required to stab through clothes into a foam–silicone rubber skin simulant. The results show that the force required can be significantly different, particularly when layers of clothing are penetrated. A cotton t‐shirt adds c. 8 N to the penetration force, while a T‐shirt and jacket can add an additional 21 N. The results allow a more quantitative assessment of forces required in stabbing.     

De Novo Advanced Adult‐Onset Offending: New Evidence from a Population of Federal Correctional Clients

Adult antisocial behavior is almost always predated by delinquency during childhood or adolescence; however, there is also evidence of adult‐onset criminal offending. This study examined this controversial subgroup of offenders using self‐reported and official data from a total population of federal correctional clients selected from the Midwestern United States. Difference of means t‐tests, chi‐square tests, and logistic regression models found that 11.7% of clients had an adult onset of offending and 2.7% of clients (n = 23) had an onset occurring at age 60 years or older. This group—introduced as de novo advanced adult‐onset offenders—had high socioeconomic status, mixed evidence of adverse childhood experiences, and virtually no usage of drugs with the exception of alcohol. These offenders were primarily convicted of social security and white‐collar crimes and evinced remarkably low psychopathology and criminal risk. More research is needed to replicate the phenomenon of de novo advanced adult‐onset offending.     

Comparative Evaluation of Potentially Radiolucent Projectile Components by Radiographs and Computed Tomography

Projectile components that are traditionally radiolucent can be of considerable importance in determination of weapon type and caliber, but they are often missed on evaluation of postmortem radiographs. We hypothesized that these components would be significantly better visualized by evaluation of computed tomography (CT) scans compared to the practice standard of radiography alone. In this project, potentially radiolucent projectile components were both pulled apart and fired, and the radiolucent components were recovered. These components were embedded in blocks of ballistics gelatin and were imaged using both radiography and CT. The scans were evaluated by three blinded, board‐certified radiologists for the presence/absence of projectile components and true‐negative regions in each block. If a radiologist indicated visualization of a projectile component, they were further requested to describe their observation. It was found that traditionally radiolucent projectile components are not significantly more often identified on CT scans than radiography (p < 0.05).     

Development of an information sheet providing rapport advice for interpreters in police interviews

Abstract

The present paper reports the development of an information sheet designed to aid interpreters in police interviews in recognizing, conveying and inadvertently obstructing rapport-building efforts by police interviewers. The contents of this sheet were informed by past research defining rapport, and rapport uses in police interviews. We used a mixed experimental design to test the information sheet. One group (Intervention, n = 35) was randomly assigned to read an information sheet before responding to short vignettes of police interviewing foreign non-English speaking suspects about international crimes, while another (Control) group (n = 37) simply responded to the vignettes. Perceptions of rapport cues by the intervention group exceeded that of the control group. However, the groups performed equally well at identifying appropriate methods to convey/avoid obstructing rapport. Feedback from the intervention group on the helpfulness of the information sheet was largely positive. The findings were used to improve the information sheet which can be used to alert interpreters to the importance of rapport in suspect interviews.     

Piercing the surface: A mechanical analysis of stabbing with household tools

Estimating the applied power during a stabbing incident, or estimating the minimal force necessary to penetrate the body with a certain weapon is a challenging task in forensic practice. A thorough forensic evaluation of stabbing forces needs objective numerical experimental data. Stabbing tests of 12 different weapons – including knives, a pair of scissors, a fork, screwdrivers, a rasp, a corkscrew, and a utility knife blade – were performed with a Mecmesin MultiTest-dV material tester on pork loin and ballistic gel to estimate the stabbing forces and dynamics. Penetration force (F_p) and maximal force (F_max) were recorded, and the registered force curves were analyzed. F_max was 159.8–212.07 Newton (N), 30.56–30.58 N, 168.9–185.48 N for various knives; 171.39–190.43 N for the pair of scissors, 233.6 N for the fork; 532.65–562.65 N, 370.31–367.19 N and 314.51–432.89 N for various screwdrivers, 44.14–56.62 N for utility knife during pork loin stabbing. The butter knife, corkscrew and rasp were not able to penetrate the pork loin, and the curved fork bent during stabbing. The results prove that weapon characteristics greatly influence the force necessary for penetration. Maximal stabbing force depends mostly on tip sharpness, and the force sharply decreases after penetration occurs, which indicates that edge sharpness is not as important as tip characteristics during stabbing perpendicular to skin surface. The penetration force during stabbing with a pair of scissors is comparable to the penetration force of knives. Stabbing with screwdrivers generally needs larger force than average knives but depends greatly on screwdriver size.