Pathology Services Wound Analysis Wound type may vary from bullet, stabbing, blunt force, rape, poisoning considered to be toxicological domainburn, or traffic fatality.
Gunshot Residue Collection Page Content When a firearm is shot, in addition to the projectile sa mass of debris comes out the muzzle. These gunshot residues GSR can include various primer residues, residues from projectiles, and partially burned and unburned gun powered particles.
The examination and analysis of GSR on items of evidence can allow determinations to be made as to weather a hole or defect is consistent with being caused by a bullet or other firearm-related projectiles. Once in the Laboratory, the Firearms Section can examine patterns of GSR on items of evidence to determine muzzle-to-target distance.
Additionally, GSR can be transferred to an individual by discharging a firearm, handling a firearm or fired ammunition components, or by contact with another object that has GSR on it.
The presence of GSR on a person may provide useful information linking an individual with an action that could transfer this residue to them.
As a very general guide, after four to eight hours it is unlikely that residues will be found on a live and mobile individual's hands unless steps have been taken to preserve such evidence e.
The residue can persist for longer periods of time on some areas of interest such as on the deceased, on clothing or other stationary objects. The decision to collect a sample is affected by many variables and must be based on the investigative information available.
This type of analysis is not performed by the Laboratory, but the crime scene team will collect samples for analysis by an outside laboratory. The Laboratory can provide a list of outside laboratories that will do this examination for a fee. The image below shows GSR coming from the muzzle and cylinder gap of a revolver that has just been fired.Gunshot Residue Analysis (GSR Testing) McCrone Associates has been performing gunshot residue (GSR) analyses for more than 20 years—first using electron microprobes (EMPA) and more recently scanning electron microscopes (SEM) equipped with energy dispersive X-ray spectrometry (EDS) detectors for elemental composition of materials.
Written by the nation's foremost authority on gunshot wounds and forensic techniques as they relate to firearm injuries, Gunshot Wounds: Practical Aspects of Firearms, Ballistics, and Forensic Techniques, Second Edition provides critical information on gunshot wounds 5/5(1).
If a GSR Analysis Information Form is present in the kit, label the top of the form with the Laboratory case number, unique sequential number, Laboratory item number, Forensic Scientist’s initials, the date, and the subject’s last name.
Gun Shot Residue Testing: Is it Still a Viable Form of Physical Evidence? Compiled by Don Penven.
Gun Shot Residue, or simply GSR, is a means of testing for the presence of certain materials on the hands and clothing of a subject in hopes of determining that this individual may have discharged a .
Forensic investigation: trace evidence analysis for gun-shot residue. Introduction. The ability to identify gunshot residue has provided solution to the problems encountered in the resolution of forensic science, legal medicines, and for shooting distance determination.
Gunshot wounds can be either penetrating or perforating. In a penetrating wound, the bullet enters an object and remains inside, while in a perforating wound, the bullet passes completely through the object.