Utilizing a magnetic locator to search for buried firearms and miscellaneous weapons at a controlled research site

Forensic personnel generally use basic all-metal detectors for weapon searches because of their ease of use and cost efficiency. For ferromagnetic targets, an alternative easy to use and low-cost geophysical tool is a magnetic locator. The following study was designed to demonstrate the effectiveness of a common, commercially available magnetic locator in forensic weapon searches by determining the maximum depth of detection for 32 metallic forensic targets and testing the effects of metallic composition on detection. Maximum depth of detection was determined for 16 decommissioned street-level firearms, six pieces of assorted scrap metals, and 10 blunt or bladed weapons by burying each target at 5-cm intervals until the weapons were no longer detected. As expected, only ferromagnetic items were detected; weapons containing both ferromagnetic and nonferromagnetic components were generally detected to shallower depths. Overall, the magnetic locator can be a useful addition to weapon searches involving buried ferromagnetic weapons.     

Sequential monitoring of burials containing small pig cadavers using ground penetrating radar

Ground-penetrating radar (GPR) was used to monitor 12 pig burials in Florida, each of which contained a small pig cadaver. Six of the cadavers were buried in sand at a depth of 0.50-0.60 m, and the other six were buried in sand at a depth of 1.00-1.10 m to represent deep and shallow burials that are generally encountered in forensic scenarios. Four control excavations with no pig interment were also constructed as blank graves and monitored with GPR. The burials were monitored for durations of either 13 or 21 months, and were then excavated to correlate the decomposition state of the cadaver with the GPR imagery. Overall, this study demonstrated that it may be difficult to detect small cadavers buried in sand soon after they are skeletonized because the area surrounding the body, or the grave, may not provide a strong enough contrasting area to be detected by GPR when compared to that of the surrounding undisturbed soil. Also, depth of burial appears to influence grave detection because bodies that are buried at deeper depths may be detected for a longer period of time due to reduced decomposition rates.     

Homicide by unusual‐edged weapons: Forensic considerations of two cases

Homicide by stab wound is common worldwide. However, the use of unusual edged weapons is rarely reported in the forensic literature. Here, we report two cases of homicide involving a Japanese sword, or katana, and a sickle. Both of these weapons can create either stab or incised wounds with some particularities. In our cases, characteristics of the external wounds, internal injuries, and the depth of penetration raised the possibility of an unusual weapon. Meticulous forensic examination of these injuries (morphological characteristics, depth of penetration, trajectories, and cut marks in the bone) may allow the forensic expert to determine the type of weapon used.     

Distribution of textile fibers in the path of a bullet

Twenty-one blocks consisting of 20% gelatin were fired at using firearms of the long rifle caliber .22 and .357 Magnum. The frontal area of these blocks was prepared with textile coverings marked with technetium 99m. Two gunshot series of each type were fired at summer, interseasonal, and winter clothing, using different ammunition. The radioactivity of the bombarded blocks was measured by single photon emission computed tomography (SPECT). The results of these gun shot series were presented graphically and compared. Initially (at 2 cm depth), high radioactivity is always detected, which among other things is caused by the defilement of the bullet's surface when shot through the textile covering marked by technetium. The higher radioactivity in the middle and deeper block areas is the result of fiber infiltration. Accordingly, there are greater fiber accumulations in the middle and deeper areas of the path of the bullet. This is the case mainly in thinner clothing (summer). Heavier clothing (autumn, winter) presents a greater obstacle for bullets with greater impact as well. Here, only projectiles having a lesser tendency to deform, as well as a high impact, transport a considerable proportion of textile fibers into the deeper parts of the blocks.     

Preventing lethal violence in schools: the case for entry-based weapons screening

Violence-related behavior in schools has declined in recent years, but the perception of risk remains high. Disturbingly high percentages of students and teachers report staying home out of fear, and many students bring weapons to school for protection. Current proposals for preventing school violence include punishing the violence-prone, expulsion for weapon carriers, and creating a culture of nonviolence through various behavioral methods like conflict resolution. None of these proposals address the issue of lethal violence and hence personal safety. The risk of lethal violence in schools (related mainly to firearms) could be substantially reduced by creating an effective barrier between firearms and people. This could be achieved by using entry-based weapons detection systems similar to those now used in airports and courts. Decreasing the risk and fear of violence by converting schools into weapons-free zones would also be expected to increase attendance and improve scholastic performance. Randomized, controlled studies should be undertaken to evaluate the efficacy and cost-effectiveness of entry-based weapons detection systems for achieving these outcomes.     

Searching for graves using geophysical technology: field tests with ground penetrating radar,magnetometry, and electrical resistivity

Field experiments were conducted using three types of geophysical equipment in a variety of situations. The goal of the study was to ascertain the relative utility of this technology for non-geophysical expert forensic professionals searching for buried human remains. The study concludes that the equipment should be used with caution after a critical evaluation of specific field conditions, and more refinement of technical methods and skills should be developed.     

Detection of firearm imprints on the hands of suspects: effectiveness of PDT reaction.

Pyridyldiphenyl triazine (PDT) and three of its analogues were compared as practical reagents for visualizing unseen impressions left on the hands of a person who has held a firearm. The parent compound, PDT, gave the best results using intensity and clarity as measuring criteria. The effectiveness of the PDT reaction was then studied on 147 volunteers who had held firearms in their hands. Identifiable impressions of the metallic parts of the weapons were developed on the hands of 103 volunteers (70%). Results with females were slightly higher than with males, however, the difference was possibly statistically insignificant, and needs further study. Ferroprint and Ferrotrace, 5 commercial preparations that are based on the PDT reaction, have become a part of the professional equipment of every crime scene technician in Israel.     

A comparison of penetration and damage caused by different types of arrowheads on loose and tight fit clothing

Bows and arrows are used more for recreation, sport and hunting in the Western world and tend not to be as popular a weapon as firearms or knives. Yet there are still injuries and fatalities caused by these low-velocity weapons due to their availability to the public and that a licence is not required to own them. This study aimed to highlight the penetration capabilities of aluminium arrows into soft tissue and bones in the presence of clothing. Further from that, how the type and fit of clothing as well as arrowhead type contribute to penetration capacity. In this study ballistic gelatine blocks (non-clothed and loose fit or tight fit clothed) were shot using a 24 lb weight draw recurve bow and aluminium arrows accompanied by four different arrowheads (bullet, judo, blunt and broadhead).The penetration capability of aluminium arrows was examined, and the depth of penetration was found to be dependent on the type of arrowhead used as well as by the type and fit or lack thereof of the clothing covering the block. Loose fit clothing reduced penetration with half of the samples, reducing penetration capacity by percentages between 0% and 98.33%, at a range of 10 m. While the remaining half of the samples covered with tight clothing led to reductions in penetration of between 14.06% and 94.12%.The damage to the clothing and the gelatine (puncturing, cutting and tearing) was affected by the shape of the arrowhead, with the least damaged caused by the blunt arrowheads and the most by the broadhead arrows. Clothing fibres were also at times found within the projectile tract within the gelatine showing potential for subsequent infection of an individual with an arrow wound.Ribs, femur bones and spinal columns encased in some of the gelatine blocks all showed varying levels of damage, with the most and obvious damage being exhibited by the ribs and spinal column.The information gleaned from the damage to clothing, gelatine blocks and bones could potentially be useful for forensic investigators, for example, when a body has been discovered with no weapons or gunshot residue present.     

Unusual blunt force wound produced by a gun muzzle

Most blunt force injuries produced by guns are associated with gun butts, and patterned, muzzle/sight impressions are usually produced by discharging firearms. An unusual and distinct forehead laceration produced by a blow with the muzzle end of a .32 caliber revolver is presented.     

Preliminary Observations of Arthropods Associated with Buried Carrion on Oahu

Several studies in Hawaii have focused on arthropod succession and decomposition patterns of surface remains, but the current research presents the first study to focus on shallow burials in this context. Three domestic pig carcasses (Sus scrofa L.) were buried at the depths of 20–40 cm in silty clay loam soil on an exposed ridge on the leeward side of the volcanically formed Koolau Mountain Range. One carcass was exhumed after 3 weeks, another after 6 weeks, and the last carcass was exhumed after 9 weeks. An inventory of arthropod taxa present on the carrion and in the surrounding soil and observations pertaining to decomposition were recorded at each exhumation. The longer the carrion was buried, the greater the diversity of arthropod species that were recovered from the remains. Biomass loss was calculated to be 49% at the 3‐week interval, 56% at the 6‐week interval, and 59% at the 9‐week interval.     

The criminal use of improvised and re-activated firearms in Great Britain and Northern Ireland.

Following the Hungerford Massacre the British Government imposed additional strict firearms legislation in 1988 that involved several classes of arms being placed into the prohibited category. By way of compensation a scheme was introduced to allow the unrestricted possession and transfer of the newly prohibited arms, other firearms and "prohibited weapons", if de-activated to a standard acceptable to the Secretary of State. Approved standards for firearm de-activation were drawn up in 1989. The inspection of the de-activated arms was devolved to the two Gun Barrel Proof Houses at London and Birmingham, as otherwise the task of inspecting the thousands of guns involved would have overloaded the firearms section at the Huntingdon Forensic Science Service Laboratory, who were already dealing with criminal firearms cases submitted by 41 of the 43 police forces throughout England and Wales, as well as providing technical assistance to the Home Office and Government Ministers. Members of the Gun Trade made representations to the Minister involved during the initial stages of setting up the official de-activation standards. This resulted in some measure of compromise in the range and nature of the de-activation requirements. Although it was clear that some individuals possessing the necessary skill and equipment might attempt to restore the odd weapon to a working condition, the scheme appeared to work reasonably well for the next few years. However, over the passage of time, criminal casework submissions to the Huntingdon Laboratory from industrial city areas along the M62 corridor of northern England revealed a steadily growing trend in the use of re-activated arms, which in a significant number of cases involved the use of fully automatic weapons. At first, the nature of the re-activation processes used to restore these arms was quite crude. However, with the passage of time a steady improvement in the machining and welding skills used by the some of the culprits involved became more and more apparent, as was a move by them to bulk restoration. The use of restored arms in serious and often drug related crime, spread to the other mainland British cities, and eventually to Northern Ireland. More rigorous de-activation standards were introduced in 1995 to help counter this perceived threat, particularly in respect of handguns and full-automatic weapons. Blank cartridge pistols and air cartridge pistols were also being modified to allow their use with bulleted ammunition in the commission of criminal offences. As a result all air cartridge guns were placed into the prohibited weapons category in 2003, and the possession of imitation firearms in a public place without good reason, also became an offence. The Government is now considering further legislation, which will affect the sale of replica firearms and cartridge reloading equipment and materials.     

Pulse Variations of a Conducted Energy Weapon (Similar to the TASER® X26 Device): Effects on Muscle Contraction and Threshold for Ventricular Fibrillation*

Abstract: Conducted energy weapons (such as the Advanced TASER X26 model produced by TASER International), incapacitate individuals by causing muscle contractions. To provide information relevant to development of future potential devices, a “Modifiable Electronic Stimulator” was used to evaluate the effects of changing various parameters of the stimulating pulse. Muscle contraction was affected by pulse power, net/gross charge, pulse duration, and pulse repetition frequency. The contraction force increased linearly as each of these factors was increased. Elimination of a precursor pulse from X26‐like pulses did not have a significant effect on the normalized force measured. Muscle‐contraction force increased as the spacing increased from 5 to 20 cm, with no further change in force above 20 cm of spacing. Therefore, it is suggested that any future developments of new conducted energy weapons should include placement of electrodes a minimum of 20 cm apart so that efficiency of the system is not degraded. In the current study, the 50% probability of fibrillation level of X26‐like pulses ranged from 4 to 5 times higher than the X26 itself. Relatively large variations about the X26 operating level were found not to result in fibrillation or asystole. Therefore, it should be possible to design and build an X26‐type device that operates efficiently at levels higher than the X26.     

The Camorra closely observed

An article that discusses how information and communications technology (computer systems and data transmission) are used as ‘cyber weapons’ for criminal purposes. It canvasses a number of legislative policy options for controlling their misuse. The paper concludes with the view that implementing some form of cyber weapons laws – in the same vein as firearms legislation – would not only help ensure society's domestic well-being, but would also aid national security.     

Characteristics and dynamics of illegal firearms markets: Implications for a supply-side enforcement strategy

The question of whether the illegal firearms market serving criminals and juveniles can be disrupted has been vigorously debated. Recent research suggests that illegal gun markets consist of both “point sources” (ongoing diversions through scofflaw dealers and trafficking rings) and “diffuse sources” (acquisitions through theft and informal, voluntary sales). To the extent that systematic gun trafficking is an important source of weapons for criminals and youth, focused regulatory and investigative resources may be effective in disrupting the illegal flow. In this research, we use data on traced firearms to examine one aspect of the illegal gun market that holds the most immediate promise for focused supply-side enforcement efforts—close-to-retail diversions. We find that almost one-third of traceable crime guns were recently diverted from legitimate retail firearms commerce and that nearly one-third had two or more indicators of gun trafficking involving dealers, purchasers, and possessors. We discuss the implications of these findings for understanding illegal gun markets and for developing effective supply-side enforcement strategies.     

Unusual blunt force wound patterns due to a hexagonal steel bar

Pathologists routinely examine victims with blunt force traumatic injuries. Many of these victims exhibit injury patterns that can help identify the weapon used in the assault. Proper documentation that accurately portrays the injury pattern and allows for comparison with recovered weapons is therefore essential. Our office investigated a homicide with unusual blunt force injuries. This article presents the procedure that we followed to identify the weapon.     

Weapons used by juveniles and adult offenders in U.S. parricide cases

In recent decades, attention has focused on juveniles who kill their parents. Research has indicated that increases in juvenile homicide have been associated with the availability of firearms, but little is known about the weapons juveniles use to kill their parents and whether their weapon usage is different from that of adult children who kill their parents. This article uses Supplementary Homicide Report data for the 24-year period 1976 to 1999 to investigate weapons selected by parricide offenders to kill biological mothers and fathers. Significant differences were found in the weapons used in matricide and patricide incidents and in the weapons selected by juvenile and adult offenders. A comparison with an earlier study by Heide revealed that weapon usage in parricide events is stable. Differences found in both studies between weapons used to kill parents and offender age are consistent with a physical strength hypothesis proposed by Heide in 1993.     

Aiming at the chest, but hitting the back

Gunshot injuries in the back may suggest the unjustified use of firearms. A wound in the back inflicted by a firearm should not automatically imply that the shooter aimed at the back. A previous study demonstrated that it is possible for men to turn their trunk faster than it takes for a shooter to fire or throw a hand-operated weapon. With a high speed motion camera the authors were able to demonstrate that it is also possible for women to turn their trunk fast enough, so that a shot in the back could have been aimed at the front of the body. This conclusion is also likely to apply to hand-operated or thrown weapons, since the velocity of their projectiles is considerably lower than that of firearms.     

Weapon Use in Korean Homicide: Differences Between Homicides Involving Sharp and Blunt Instruments

On the basis of information regarding 276 homicides committed in South Korea between 1987 and 2008, we compared offenders’ and victims’ characteristics, injury locations, weapon‐related behavior, and offending behavior between homicides involving sharp and blunt instruments. The victims of sharp‐force homicide were much younger relative to those of blunt‐force homicide. In addition, homicides involving blunt instruments were more likely to be committed by offenders who lived with the victims. Most sharp‐force homicides involved injuries to the torso, while blunt‐force homicides involved mainly head injuries. Furthermore, perpetrators of sharp‐force homicides tended to preselect their weapons, while those of blunt‐force homicides were likely to use weapons of opportunity. Logistic regression analysis identified a number of factors, including injury location and body transportation, which significantly predicted weapon type. As this was the first South Korean study to compare sharp‐ and blunt‐force homicides, the results have practical implications for homicide investigations.     

Intentional Homicide: A Fifteen-Year Study (2000–2014) at the Department of Forensic Medicine,University of Rome “Sapienza”

This study analyzes postmortem records from 260 homicide cases autopsied by the Department of Forensic Medicine in Rome from 2000 to 2014. The victims were mainly males (74%) and young (61% aged from 21 to 50 years). Although the victims were mostly Italians, the number of foreign victims (33%) has increased since 1990, primarily due to immigration. The offenders frequently used firearms (39%), particularly in multiple murders. An increase in blunt (20%) and sharp force (32%) weapons was also seen. The primary crime scene was residential (42%), and the head was the most frequently injured body region. Male victims occurred frequently in the context of organized crime (7.6%). In family or intimate-sexual relationships, women were the majority of victims (8%). Forensic pathologists play an important role during investigation. They should consider all the information available to them, including autopsy information, crime scene information, and crime investigation data.