Firearm and Tool Mark Analysis is exactly what it sounds like – a compilation of those two separate sciences. They have come to be associated together because by practicing one of those skills, the person generally will have the knowledge and intuition to practice the other. By definition, firearms identification is a discipline mainly concerned with determining whether a bullet or cartridge was fired by a particular weapon (Saferstein, 460). A tool mark is any impression, cut, gouge, or abrasion caused by a tool coming into contact with another object (Saferstein, 481). Depending on the stage of the investigation, the science can be performed by crime scene investigators, CSIs, as well as experts that analyze the firearms or tool marks in a laboratory setting. If the crime scene is being evaluated and combed for bullets, weapons, or tool marks, it is up to the crime scene investigator to find the evidence. Once the investigator has found it, however, it then makes its way to the firearm and tool mark examiner who will analyze all of the markings that the CSI may have found and couldn’t readily identify.
Objects for analysis can be found in a good number of places. When looking for firearm evidence, a bullet can be lodged in a body, an object, a wall, or in some cases, could have come to stop on the ground. CSIs must also check around the area the gun was believed to be fired and the suspect’s hands for gunshot residue. Searching for gunshot residue is normally done only at the crime scene as to confirm/disaffirm a suspect as soon as possible because the residue can be washed from hands and clothing cleaned. Furthermore, there can be tool marks almost anywhere. It is less likely to have tool marks appear on a body, but it is not...
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...ttest to the validity of other examiner’s findings. The most an examiner can do outside of relaying actual facts, is give their opinion on how the bullets or markings would end up in the location they were found. The most important thing to reiterate and remember is something that is becoming true in many forensic cases – an examiner has almost no say in what the evidence shows. In the case of firearms and tool marks, this is very true; the evidence speaks for itself.
Works Cited
“Career.” FirearmsID. Web. 2/16/10
“Daubert Standard.” Wikipedia. Web. 2/16/10
“Firearms and Tool Marks in the FBI Laboratory.” Federal Bureau of Investigation. Web. 2/16/10
“Frye Standard.” Wikipedia. Web. 2/16/10
“History of Firearms.” FirearmsID. Web. 2/16/10
Saferstein, Richard. “Criminalistics: An introduction to Forensic Science.” Upper Saddle River: Pearson Education. 2007
If there was no weapon found at the scene and there are other evidence clues that lead to a suspect, and if the suspect had a firearm the forensics team would get a warrant to retrieve the weapon so it could be tested. When the weapon is being tested, it will allow the the bullet have individual marks that will be compared to the ones found at the scene. All of these comparisons are done under a microscope since technology has improved and it is easier to make matches. According to Young & Ortmeier (2011) “class characteristics include weight of the projectile, direction of twist of the riffling, degree of twist of riffling, number of lands and groves, and width of lands and groves.” Even though guns from the same manufacture will never have the same riffling, lands or grove. When evaluating two cartridge casings the examiner will be looking for manufacture, the size of the firing pin as well as the location. The FBI has made a integrated ballistic identification system (IBIS) it's a database that helps crime labs with comparisons where it proves one gun being used in many crimes. In addition, gunshot residue is helpful solving crimes because gunshot residue can be chemically tested. If an individual has gunshot residue it doesn't prove he or she shot the victims, it just means that they were along the premises while the gun was fired. Another
Evidence analysis and ranging is the most crucial stage of investigation. The success of the case exposure lies in the gradual evidence research and collecting prior to the laboratory analysis. The CSI systematically makes his way through the crime scene collects all potential evidence, tagging, logging and packaging so it remains intact on its way to the lab. Depending on the task breakdown of the CSI unit he may or may not analyze the evidence in the lab.
CSIs must photograph/sketch crime scenes, take measurements, make observations, testify against criminals in court, and collect, pack, label, document, and analyze evidence (Career Cruising). All of these tasks CSIs must complete, require them to handle a variety of tools including: cameras, tripods, flashlights, notepads, utensils to collect physical evidence, measuring tapes, rulers, microscopes, fingerprinting kits, and even guns in some cases (Career Cruising). CSI agents collect to different types of evidence, when they investigate a crime (Byrd). The first type of evidence is testimonial evidence, which is the answers CSIs questioning suspects and witnesses are given (Byrd). Physical evidence, which is the other type of evidence, is any type of three-dimensional evidence collected at a crime scene (Byrd). Although different CSI teams from different areas of the world can consist of multiple branches, including: detectives, technicians, medical examiners, scientists, and lab analysts, they still use forensics, which is science and technology, to investigate crimes (Zullo). There is always crime, but when there are no current cases; CSIs go back to old/previous cases (McFadden).
Crime scenes are known to have many clues left behind. The obvious would be a the body or bodies, clothing, and sometimes even the murder weapon. While these are great way to solve a case there's another kind of evidence; trace evidence. Trace evidence are small pieces of evidence that are laying around a crime scene. There are many types of trace evidence some of them include metal filings, plastic fragments, gunshot residue, glass fragments, feathers, food stains, building materials, lubricants, fingernail scrapings, pollens and spores, cosmetics, chemicals, paper fibers and sawdust, human and animal hairs, plant and vegetable fibers, blood and other body fluids, asphalt or tar, vegetable fats and oils, dusts and other airborne particles, insulation, textile fibers, soot, soils and mineral grains, and explosive residues. Although these are the most common found elements, they are not the only ones. The Trace Evidence Unit is known to examine the largest variety of evidence types and used the biggest range of analytical methods of any unit. materials are compared with standards or knowns samples to determine whether or not they share any common characteristics. In this paper I will discuss the different kinds of trace evidence and how crime scene investigaros use it to solve cases and convict criminal.
The most easily recognized forms of firearm evidence could include the weapon itself, bullets, and cartridge casings. These alone can tell investigators the gauge of the gun, the manufacturer or marketer, and unique individual characteristics that can identify a particular firearm (Firearms evidence, n.d.). By looking a little closer at the bullet wounds themselves, investigators may also be able to find gunshot residue and gunpowder patterns. All guns are engraved with the serial number, and even if it has been filed away, it can be restored and identify the owner of the
The criminal justice system has changed a lot since the good old days of the Wild West when pretty much anything was legal. Criminals were dealt with in any fashion the law enforcement saw fit. The science of catching criminals has evolved since these days. We are better at catching criminals than ever and we owe this advancement to forensic science. The development of forensic science has given us the important techniques of fingerprinting and DNA analysis. We can use these techniques to catch criminals, prove people's innocence, and keep track of inmates after they have been paroled. There are many different ways of solving crimes using forensic evidence. One of these ways is using blood spatter analysis; this is where the distribution and pattern of bloodstains is studied to find the nature of the event that caused the blood spatter. Many things go into the determination of the cause including: the effects of various types of physical forces on blood, the interaction between blood and the surfaces on which it falls, the location of the person shedding the blood, the location and actions of the assailant, and the movement of them both during the incident. Another common type of forensic evidence is trace evidence. This is commonly recovered from any number of items at a crime scene. These items can include carpet fibers, clothing fibers, or hair found in or around the crime scene. Hairs recovered from crime scenes can be used as an important source of DNA. Examination of material recovered from a victim's or suspect's clothing can allow association to be made between the victim and other people, places, or things involved in the investigation. DNA analysis is the most important part of forensic science. DNA evidence can come in many forms at the crime scene. Some of these forms include hair; bodily fluids recovered at the crime scene or on the victim's body, skin under the victim's fingernails, blood, and many others. This DNA can be the basis of someone's guilt or innocence; it has decided many cases in the twentieth century. As the times continue to change and the criminals get smarter we will always need to find new ways to catch them. Forensic science is the most advanced method yet, but is only the beginning. As the field of science grows so will the abilities of the
In today’s time, modern Crime Scene Investigation has increased rapidly. From throughout the late 1900’s and in the early 2000’s (Taylor 1). For all of the evidence that they find, a solid foundation has formed over the thousands of years of Crime Scene
Whereas the real picture of forensic evidence is unlike what is represented in movies and television shows where a fingerprint or a trace of hair is found, then it’s game over for the criminal. Reality is not as straightforward. As more people are exposed to the unreal forensic world through television and media the likeliness for a wrong conviction increases with juries assuming the evidence involves more science than what it really does, this is known as the CSI Effect. Further education and training is needed for the people of the court, the forensic specialists, and so called experts. The people in courts do not question any of the ‘professionals’ and just trust in their expertise. The court could overcome this perception by requiring explanation of error rates in a forensic field. To do this, testing examiner error rates will be necessary which means further research. Forensic science has such a large effect on the prosecution of suspects, experts have been known to provide questionable and at times incorrect evidence. When a false conviction occurs the true perpetrator is set free. Once realized, the public doubts the justice system and the reliability of the forensic evidence even more. At this point in time, forensic is an inexact
Collecting evidence from a crime scene is a crucial aspect of solving crimes. Before evidence can be seized, there must first be a court order approving the search of the crime scene and the seizure of the evidence found at the scene. Standard protocol for officers is for them to always use latex gloves, avoid plastic bags, double wrap small objects, package each object separately, and to collect as much evidence as possible. It is better to have too much evidence than to not have enough. There are countless amounts of evidence that can be found at a crime scene.
Imagine pulling into your driveway and seeing your neighbor’s house surrounded by police, flashing lights, and caution tape with bodies covered in white sheet on the lawn. It was a drive by shooting. Next, a van pulls up and a Criminal Investigator steps out and starts assessing the crime scene. She begins taking photos, marking shell casings, packaging evidence, documenting tire treads on the pavement and inspecting and collecting DNA evidence from the bodies. Criminal Investigators are highly trained college graduates that are a vital part of bringing criminals to justice.
Forensic Science, recognized as Forensics, is the solicitation of science to law to understand evidences for crime investigation. Forensic scientists are investigators that collect evidences at the crime scene and analyse it uses technology to reveal scientific evidence in a range of fields. Physical evidence are included things that can be seen, whether with the naked eye or through the use of magnification or other analytical tools. Some of this evidence is categorized as impression evidence2.In this report I’ll determine the areas of forensic science that are relevant to particular investigation and setting out in what method the forensic science procedures I have recognized that would be useful for the particular crime scene.
investigators take from the crime scene. With scientific methods it helps investigators to produce a
The transitional growth in the forensic science sector has not been without challenges. Though the world has experienced increased capabilities and scientific knowledge, which has led to faster investigations and results, many forensic experts have argued that forensic laboratory testing, in the light of 21st century technological advancements, is yet to meet the expected rate in quick available testing and analysis (Mennell & Shaw, 2006). This is with respect to the growing rate of crime and the high demand of quick crime scene testing and analysis. In the science of crime scene, analysis and interpretation of evidence is majorly dependent on forensic science, highlighting the change in the role of forensic sciences (Tjin-A-Tsoi, 2013). In the business of forensic science, time is beginning to play important role in the evidence testing and analysis which is becoming crucial in reducing ...
Much like in Toms case, most investigations start with a crime having been committed. Forensic ballistics and firearm investigation start when there are bullets, cartridges, a weapon, or any combination of the above found at a crime scene. With the evidence, a crime lab can search for clues on these items that could lead to a suspect or possibly prove that the items were used in the crime. By comparing the markings on bullets or cartridges found at the scene with those fired from a suspect’s weapon, a ballistics expert can often determine if the rounds came from the same weapon. Just the act of cycling a cartridge through a weapon without firing it can leave permanent scratches in the case that are unique to the weapon.
In the earliest part of the last century (1900-1930) such scientific analysis of firearms and tool-mark identification became a recognized science in several worldwide judicial systems due to vast research by pioneering examiners such as Colonel Calvin Goddard, a professor of police science at Northwestern. In 1925 Goddard wrote an article for the Army Ordnance titled "Forensic Ballistics" in which he described the use of the comparison microscope regarding firearms investigations, in April of that same year, Goddard along with several others established the Bureau of Forensic Ballistics, which was formed to provide firearms identification services throughout America. Goddard researched, authored and spoke extensively...