The determination of how far a firearm was from a victim or target when it was discharged is a frequent request to crime laboratories. This determination requires test firing the firearm at various distances to compare gunshot residue patterns made during the test with patterns on the victim or target. Crime laboratories stipulate that the same firearm and ammunition used in commission of the crime must be used for this testing; however, little empirical evidence exists supporting this requirement. It was the purpose of this study to determine if there were any significant differences using different firearms and different ammunition in distance determination testing. The findings indicated that no significant differences occurred with different firearms but there were significant differences with different brands of ammunition.

In many cases of crimes involving a firearm, police investigators need to know how far the firearm was held from the victim when it was discharged. Knowing this distance, vital questions regarding the re-construction of the crime scene can be known. Often, the original firearm used in commission of a suspected crime is not available for testing or is damaged. Crime laboratories require the original firearm in order to conduct distance determination tests. However, no empirical research has ever been conducted to determine if same make and model firearms produce different results in distance determination testing. It was the purpose of this study to determine if there are significant differences between the same make and model of firearms in distance determination testing. The findings indicate no significant differences; furthermore they imply that if the original firearm is not available, another firearm of the same make and model may be used.

The range at which a weapon has been fired is an important measurement for the reconstruction of firearms offenses (murder, suicide, accident). All changes caused by a shot and which vary according to the distance from the weapon are suitable in principle for determining this distance. However, some procedures are very elegant in theory but hardly applicable in practice. The constructions of ammunition and the sequence of events during a shot are dealt with first as this knowledge forms a basis for understanding the various methods. \ The individual zones (classes) of firing distances (contact shot, intermediate shot, distance shot) are described. In this connection, the morphological methods for determining the firing distance are discussed. From the shape and size of the powder residue distribution (soot stains, powder tattooing) and with the knowledge of the weapon and ammunition, the distance from the target can be elucidated. In this chapter, the methods of making an invisible distribution visible are also dealt with. In order to determine the range of the shot from the appearance of the wound no complicated apparatus is necessary. One can judge with the naked eye. These procedures have a great advantage over the methods discussed in the following chapter in that they give stronger proof. They are more vivid and convincing for the uninitiated (judge or jury) than abstract measurements obtained by scientific devices.

Chemical Analysis of Firearms, Ammunition, and Gunshot Residue, Second Edition continues in the tradition of the popular first edition, filling the void in forensic texts on the subject. While most books on firearms focus solely on the physical aspects of firearms, this book addresses forensic issues relating to the chemical aspects of firearms and ammunition. It draws on the latest published literature including books, scientific papers, technical reports, manufacturer’s literature, newspaper articles, and personal observations and research conducted by the author. This edition is fully updated, introducing the history and development of firearms and ammunition including advances in the chemical analysis of them. Several changes in primer compositions and the particle classification system are addressed with new techniques added on evidence collection and testing methods. Coverage details chemical aspects of forensic firearms casework with particular emphasis on the detection of gunshot residues (GSR), firearm discharge residues (FDR), and cartridge discharge residues (CDR) on a suspect’s skin and clothing surfaces. Two new chapters have been added. One deals with unusual firearms case while the other summarizes a controversial, high-profile Australian case involving inorganic and organic gunshot residue, highlighting the dangers of incorrect forensic evidence and the increased need for careful training of forensic scientists. Fully updated to reflect the latest techniques and tests for particle and chemical classification Provides a complete history of firearms and ammunition development as well as advances in the chemical analysis involved in forensic firearm casework Features a one-of-a-kind chapter on processing suspects, a crucial component in many firearms and explosives residue cases The book will serves as a useful to forensic chemists, investigators, ballistics experts, among other professionals serving in a variety of forensic disciplines.

Fully updated, the second edition of this book covers the widespread advances in digital imaging technology, techniques, and devices. It discusses the increased power, storage capacity, and use of digital cameras, laptop computers, tablets, and cell phones in forensic science. It addresses methods for presenting evidence in a courtroom, including under Frye and Daubert rules. It also explains concepts with minimal jargon, making it accessible to a wide range of photography, criminal justice, forensic, and legal professionals.

With the improvements in collection methods and analytical tools that allow more thorough analyses, gunshot residue examination has made a dramatic impact as an area of trace evidence essential to the investigation and prosecution of violent crime. Current Methods in Forensic Gunshot Residue Analysis deals with major areas of gunshot residue analysis, including current and future methods of analysis, collection techniques, interpretation of evidence, expert testimony and report writing. This text is a necessity for forensic scientists conducting this type of analysis and anyone involved in the investigation and prosecution of violent crimes involving firearms.

Shooting Incident Reconstruction, Second Edition, offers a thorough explanation of matters from simple to complex to help the reader understand the factors surrounding ballistics, trajectory, and shooting scenes. Forensic scientists, law enforcement, and crime scene investigators are often tasked with reconstruction of events based on crime scene evidence, along with the subsequent analysis of that evidence. The use and misuse of firearms to perpetrate crimes from theft to murder necessitates numerous invitations to reconstruct shooting incidents. The discharge of firearms and the behavior of projectiles create many forms of physical evidence that, through proper testing and interpretation by a skilled forensic scientist, can establish what did and what did not occur. Written by the world's most well-respected shooting scene and ballistics experts, the book addresses the terminology, science, and factors involved in reconstructing shooting incident events to solve forensic cases. It covers the full range of related topics including: the range from which a firearm was discharged; the sequence of shots in a multiple discharge shooting incident; the position of a firearm at the moment of discharge; and the position of a victim at the moment of impact. The probable flight path of a projectile and the manner in which a firearm was discharged are also discussed. Case studies illustrate real-world application of technical concepts, supported by over 200 full-color diagrams and photographs. This book will be of value to practicing forensic scientists (firearm and toolmark examiners), ballistics experts, crime scene personnel, police departments, forensic consultants (generalists), attorneys and judges, medical examiners (coroners), and forensic pathologists. - Written by the most well-respected shooting scene and ballistics experts in the world - Contains over 200 full-color diagrams and photographs that support and illustrate key concepts - Case studies illustrate real-world application of technical concepts

The updated second edition of Handbook of Firearms and Ballistics includes recent developed analytical techniques and methodologies with a more comprehensive glossary, additional material, and new case studies. With a new chapter on the determination of bullet caliber via x-ray photography, this edition includes revised material on muzzle attachments, proof marks, non-toxic bullets, and gunshot residues. Essential reading for forensic scientists, firearms examiners, defense and prosecution practitioners, the judiciary, and police force, this book is also a helpful reference guide for undergraduate and graduate forensic science students.

"Muzzle to target distance can be an important aspect in criminal investigations. For most distance determination opinions to be of value to an investigation, the range must be stated such that it gives meaningful information and the resulting bracket of muzzle to target distance must also be defended during courtroom testimony. Current measurement tools lead to subjective opinions by examiners. With objective measurements, examiners can provide improved investigative conclusions that may be defended in court with quantifiable data. Due to the rapid advancement in software technology in recent years, the ability exists to analyze targets with more accurate measurements. Currently, test targets are measured by approximate methods which utilize a high degree of subjectivity. This study examined the application of Image J, image analyzing software, for use in determining muzzle to target distance. This research examined objective data to include particulate density and Gunshot residue dispersion and carried out a statistical replicate study to determine the number of targets needed at a given distance for each gun and ammunition combination. One pistol, revolver, rifle and shotgun were selected for this study. Test targets were shot five times at distances of: 4, 8, 12, 16, 20, 24 and 28 inches for the pistol, revolver and rifle, and at distances of: 4, 8, 12 and 16 feet for the shotgun. Visual and chemical examinations were performed on test targets using standard protocol procedures, published through the National Institute of Justice (NIJ) Distance Determination Training Module (2011). The targets were digitally photographed through each step and analyzed using the aforementioned protocol and Image J, image analyzing software. Comparisons were made between the National Institute of Justice model and Image J. Data were obtained and reported using the image analyzing software for particulate count and GSR dispersion."--Abstract.