Table of Contents
Why is it important to conduct gunshot residue examination?
It is usually analyzed forensically for either of two purposes: (1) to determine whether or not a suspected shooter may have fired a firearm, or (2) to estimate the range of fire from muzzle to target.
How is gunshot residue important in determining distance?
The size and density of the pattern of residues on the object can vary with distance, allowing a firearm examiner to determine the proximity of the shooter to the target when the gun was fired. Examiners test fire the firearm used in the crime and same or similar ammunition at a variety of muzzle to target distances.
What is the importance of distance determination?
Distance determination testing is important in cases where the distance a firearm was held from a target or victim becomes crucial in establishing what occurred during the commission of a crime or to establish self-defense (Osterburg & Ward, 2004).
Are gunshot residue and distance determination the same?
To determine who may have shot the firearm, the Trace section performs gunshot residue (GSR) analysis. Shooting distance determinations are performed in an attempt to approximate firearm muzzle-to-target distance (range) at the time of a suspect firearm being discharged.
What can gunshot residue tell you?
A positive result for gunshot residue from SEM-EDX analysis can mean many things. Mainly it indicates that the person sampled was either in the vicinity of a gun when it was fired, handled a gun after it was fired, or touched something that was around the gun when it was fired.
What is the value of gunshot residue?
By using the gunshot residue pattern to determine the distance of the weapon when fired, investigators can tell whether or not the victim was holding the weapon. It is only physically possible for a human to hold a gun aimed at themself a certain distance away from their own body and still be able to pull the trigger.
What is GSR gunshot residue?
Gunshot residue (GSR), also known as cartridge discharge residue (CDR), “gunfire residue” (GFR), or firearm discharge residue (FDR), is residue deposited on the hands and clothes of someone who discharges a firearm.
What kind of information can be learned from gunshot residue GSR examination?
Terms in this set (16) What kind of information can be learned from gunshot residue (GSR) examination? They can match a bullet to firearm by inspecting the grooves and lands in the bullet, as well as matching the caliber of the bullet to the firearm. Another way is to match the striations of the bullet.
How do you analyze gunshot residue?
The adhesive disks are analyzed directly using scanning electron microscopy coupled with energy dispersive X-ray analysis (SEM-EDX). The scanning electron microscope allows the particle’s size and morphology or shape to be examined, while the X-ray detector provides elemental data on the particle of interest.