The Effects Of Gunshot Residues On A Criminal Investigation

An investigation involving a firearm is a specialty of forensic science which focuses on the examination of firearms linked to ballistics. Ballistics is related to finding out the exact flight path of projectiles. Ballistics is the area of study that examines the exact path of the bullet from the moment it leaves the muzzle of the firearm up until it hits the target. During examination many items are collected for evidence including the firearm, bullets, live ammunition, cartridge casings, trace materials such as powder residue, and anything damaged by the projectile. Firearms are often divided into three processes: Internal, External, and Terminal Ballistics. Internal refers to the inside of the firearm; the space of time in which the shooter pulls the trigger, and the when the bullet is exiting. External ballistics is the flight between leaving the muzzle of the firearm, and it striking its target. Terminal ballistics is the impact of ballistics that refers to the examination in which the projectile strikes a target. All firearms leave markings on the cartridge casings once expelled when firing. Ballistic identification and microstamping laws make it possible to link a cartridge recovered to the

Forensic ballistics and firearm investigation begin when the bullets, cartridges, a weapon, or any combination of the above found at a crime scene. With the evidence, a crime laboratory will explore for clues on some things that might cause a suspect or possible to prove that the things were used in the crime. By contrast, the markings on the bullets or cartridges found at the scene with those discharged from the suspect’s weapon, a ballistics expert will typically confirm if the rounds came from a similar weapon. Just the act of cycling a cartridge through the weapon without firing it will leave permanent scratches on the case that is distinctive to the weapon.

If it doubt, do not dust for prints, submit in person to the laboratory and request that the firearm be processed for prints. After processing the scene, the evidence should be sent to the laboratory, personal delivery is preferred. A loaded handgun may be transported in a specially constructed box which has a means of securely holding the firearm and has a metal plate blocking the muzzle. If the firearm is to be sent by mail it must be unloaded and securely packaged. At the end, make a sketch of the area which shows the location of each evidence item collected. The sketch should contain location measurements which reference each evidence item to a fixed object or a reference point. Photographs should be used to supplement notes and sketches, but not as a substitute for them. For later identification the serial number of a firearm should be recorded. Some older rifles and shotguns, may not have a serial number. If the firearm is marked for identification by scribing, the marks should be placed in a location where they will not damage the appearance or value of the

We then documented the scene and videotaped the scene. Photographs were taken, and a crime scene sketch was conducted. We found 40 caliber casings which were taken into evidence and sent to the lab. We received a hit on the print that came back to Jeffery Williams, a search warrant was issued and we went to apprehend the suspect. We immediately conducted GSR, we applied paraffin wax to his hands to see if he recently discharged a

A 9mm luger round was discovered immediately after the alert of the victim. Then two 45 GPL CP round were discovered approximately 1 inch apart from each other at 0711. Close-up and medium range pictures were then taken of the bullets. A 9mm Luger was discovered with a red stain on the bullet at 0713 approximately 1.9 feet away from the tree on the scene. A sample was then collected and sent to the lab for testing at 0716. Talking to the officers at the hospital it was found that victim never woke-up and no other evidence was discovered on the scene. A cylindrical piece of metal was found at 0719 and documented and

Firearms that are left behind at a crime scene can be extremely helpful. This evidence includes not only the firearm itself but also the ammunition used in the firearm, componets that make up the firearms, and the residue that comes out when the

First and foremost as the clinician, an background description of forensic assessments should be discussed in order for understanding when discussing a specific assessment related to Ana’s case. Assessments could be used in all levels of criminal proceedings, starting with an evaluation of the clients’ level of capacity as well as evaluation of the clients’ competency to stand trial. Assessors should assess research findings that are concerning correlations between legally relevant behaviors and testing results. Generated hypotheses and test results should be confirmed a with third party data as well. Confirmation is important during this time because the client may unknowingly or knowingly present themselves in way that may help the legal

In the event that any firearm is discovered at a crime scene there are certain steps that need to be done in order to properly collect any type of firearm evidence. If there is any kind of firearm found at the scene it should be rendered safe immediately. For safety is the first priority at any crime scene. Forensic technicians should assign an evidence number to the firearm, photograph orientation and close-up view’s, and take measurements of the firearm’s location prior to collecting it. In order to deem a semiautomatic pistol safe, the forensic technician should be wearing latex gloves an unload the weapon as follows; (Tina Young, 2011)

Along with everything else in Forensics, you want to make sure you wear the proper gloves and facemask to avoid contamination of evidence. Make sure the weapon is unloaded before you submit into the lab. In the case of a revolver you want to make sure to note stating which chamber was in the firing position.

Let us start on how to collect and process expended projectiles and cartridge casings. When collecting expended casings, projectiles and remnants of shotgun ammunition each one should be numbered, photographed and measured for placement in a crime scene sketch (Tina Young, 2011). Each one collected should be placed in a pillbox or coin envelope then those should be placed into bigger envelopes or bags (Tina Young, 2011). If a projectile is stuck in a wall the section of the wall where the projectile is located should be removed (Tina Young, 2011). If a firearm found at a crime scene the best way to link it to the crime or other crimes is to test fire it into a water tank or ballistic gel. Once this has been done, the forensic tech can then compare the bullet and casing using a microscope. (Tina Young, 2011). If the firearm is not located then the casing or bullet can be ran through the National Ballistic Database. Now that we have talked about rendering firearms safe and also how they should be processed, now we can look at what information can be gained from the firearm and the cartridges and

Other important procedures of handling firearm evidence include recording the serial number of the firearm and it matches the number on the photo, the make, the model, and caliber of the weapon. The bore of the gun should never be cleaned as well as the chamber and the cylinder before a firearm is submitted. Guns must be placed in strong cardboard or wooden boxes to avoid shifting in transit. A weapon should never be picked up by placing a pencil or other object at the end of the barrel. The best way to avoid contamination of evidence is by wearing gloves and a face

The CSI effect is “the phenomenon in which jurors hold unrealistic expectations of forensic evidence and investigation techniques” (The Economist, 2010). This phenomenon stems from the crime scene television shows. In recent years, crime-fiction television series have become more popular. These shows include CSI: Crime Scene Investigation, and Law and Order. Similarly, forensic dramas have gained popularity over the years as well. These shows include, Without a Trace, Bones, and Cold Case, approximately 100 million people watching these types of show on a regular basis. Due to the popularity of these shows court officials have become worried about what types of expectations jury members will have of court and trials (Shelton, 2008). Another

Each bullet found inside the gun should be labeled as “loaded” to know how many bullets were inside the firearm and how many were actually fired and used to kill. Do not remove cartridges from the magazine, or mark the cartridges/cases directly. Tool marks can be positively matched to a tool in the suspect's possession. Firearm safety is a must at any crime

When collecting any firearms, there should not be anything placed inside the barrel. This could potentially contaminate trace or DNA evidence on or inside the barrel or scratch the barrel, causing cross-contamination. When collecting expended cartridge casings, projectiles, and fragments of shotgun ammunition at a crime scene, each individual piece of evidence must have its own evidence item number, be photographed, and measures for placement in the crime scene diagram. Then the evidence should be placed in separate evidence bags such as coin envelopes or pill boxes that are then placed into larger evidence bags and documented and label correctly. If a projectile is lodged into a wall, it should be pried from the wall but rather have that section of the wall removed and transported to the laboratory for processing (Ortmeier,

Gunshot residue (GSR) is regarded as one of the key evidences when it comes to any kind of shooting case. It helps in determining numerous factors about the crime scene and accurate assessment of gunshot wounds. Unfortunately, it is not certain that the body found on the scene will display the characteristics of crime scene. Instead, most of the time victims are found partially/fully decomposed, submerged in water for longer period, buried or even skeletonized. The macroscopic gunshot wounds are recognizable in the early stages of death but most of the time the gunshot lesions are not distinguishable from other kind of injuries such as laceration or a stab wound due to insect activity. There is not much research conducted on the presence of