The earliest practices for examining physical evidence in crime laboratories depended merely on the microscope to study the structure and composition of matter. In the early 1950s, the scanning electron microscope (SEM) was developed and it added a new element to forensic science, which was previously unattainable within the restrictions of the ordinary light microscope. All other traditional microscopes use light coming off the specimen to produce a magnified image (Saferstein, 2011). The SEM is a special microscope in the sense that it uses electrons instead of light to produce an image. This type of microscope has allowed forensic scientists to examine a much larger variety of specimens (Scanning Electron Microscope, n.d.).
The scanning electron microscope forms an image by aiming a beam of electrons onto the specimen and observing electron emissions on a closed TV circuit (Saferstein, 2011). There is an electron beam that follows a steep passage through the microscope, which is retained inside of a vacuum. The beam flows through electromagnetic fields and lenses. This allows the beam to focus down toward the sample. Once the sample is hit by the beam, electrons and X-rays are ejected from the sample.
The SEM has many advantages over the older microscopes. One advantage is its large depth of field, which allows more of the chosen sample to be in the focus at the same time. Another advantage is that it has much higher resolution. Therefore, samples that are spaced closely together can be magnified at much higher levels. This microscope also gives the examiner much more control in the degree of magnification because the SEM uses electromagnets rather than lenses (Scanning Electron Microscope, n.d.). Another unique ad...
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...ires that the evidence is not altered during the examination so that it can be later reexamined in its initial status by another examiner. There are two kinds of SEM that are valuable for these issues, which include environmental (ESEM) and low vacuum (LVSEM). Both instruments are operated differently; however, they both allow examination without any preparation that would modify the sample. Validation means that it can be demonstrated in court that the microscope was in working order and the methods used while in operation were acceptable (Kruesemann, 2008). The SEM has many additional uses including examining bullets and studying tool marks made by firing pin impressions. This information will allow forensic scientists to determine the kind of gun that was used. The SEM has proved to be an excellent device for forensic investigations (Firearms Tutorial, n.d.)
If handled with care the evidence can be the best assistance to the crime investigator and can be used as a major proof in court. To improve the investigation any detective or expert has to admit the necessity of the non-movable items observation and processing apart from the regular movable evidence collection.
Believe it or not, wounds from a victim are also evidence. The wound can allow the investigators to match up any marks that could have been made from the weapon and therefore allows them to determine at what angle, distance, and how fast the weapon was used.
Therefore, the criminal justice system relies on other nonscientific means that are not accepted or clear. Many of forensic methods have implemented in research when looking for evidence, but the methods that are not scientific and have little or anything to do with science. The result of false evidence by other means leads to false testimony by a forensic analyst. Another issue with forensic errors is that it is a challenge to find a defense expert (Giannelli, 2011). Defense experts are required to help the defense attorneys defend and breakdown all of the doubts in the prosecutors scientific findings in criminal cases. Scientific information is integral in a criminal prosecution, and a defense attorney needs to have an expert to assist he/she in discrediting the prosecution (Giannelli,
“Advance in Forensics Provide Creative Tools for Solving Crimes.” www.ctcase.org. Np. n.d. Web. 17 March 2014.
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
One definition of a microscope is "an optical instrument that uses a lens or a combination of lenses to produce magnified images of objects." Holden Caufield can be symbolized by a microscope and its parts: the field of view, the focus, and the magnifier.
The overall goal of a forensic scientist is to determine the facts using all the available resources they were given. They give their expert opinion to the attorneys, judge, and jury, and depending on how well prepared they are, can sway the jury to either a guilty or innocent verdict (Thinkquest 2014). In general, a forensic expert must keep impeccable records of all that has b...
White, P 1992, Crime scene to court: the essentials of forensic science, Royal Society of Chemistry, London, p. 20-33.
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 ...
Forensic science has paved the way to a new world of technological advancements in solving crime, through DNA analysis, new technology such as M-Vac, improving systems such as CODIS and other investigative methods. As forensic science technology advances, the chance of an individual being able to commit a crime and walk away free without leaving any trace of evidence will lessen. While forensic science has its limitations, it can be the only way to provide an accurate account of what actually occurred at some crime scenes.
As far back as 1832, James Marsh was the first to use forensics at trial to give evidence as a chemist in 1832. Since that time forensic science and evidence has come a long way in various ways and technology to help in determine if the suspect is guilt or not, through such things as DNA testing, blood, and fingerprints. The first forensic police crime lab was created in 1910. The contributions of Dr. Edmond Locard, a French scientist and criminologist, proposed that “everything leaves a trace”. This principle is still valid today as it was so many years ago. No matter how small, the specialized trained technicians and investigators can take these methods and go to a crime scene to get evidence. “Forensic science is the application of sciences such as physics, chemistry, biology, computer science and engineering to matters of law.” (Office of Justice, 2017) These different sciences can help achieve and assist in solving a case. Forensic science has also the ability to prove that a crime was committed, it can find the elements of the crime, it can help place the suspect at the scene and whether the suspect had any contact with the victim. However, in the last several years the techniques and with the use of technology the evidence that forensic science uncovers can also exonerate an innocent individual who has been falsely accused of the
When a suspect’s weapon is examined in the lab, it will be test fired into a box filled with cotton or a tank of water to provide the examiner with the bullets and cartridges with a known history. Using a microscope, the known cartridges are compared with the ones in question. With some patience, skill, and a little luck, experts can definitively say that a certain firearm and no other fired this bullet, or ejected this cartridge.
“The word ‘forensics’ means “connected with the courtroom”; so forensic science is, therefore, concerned with gathering hard evidence that can be presented in a trial” (Innes 9). Forensic science is a science that is applied specifically to legal matters, whether criminal or civil. “Few areas in the realm of science are as widespread and important as forensic science” (Hunter 12). Forensics is the one science that is most commonly used in everyday life. It is also a branch of science that incorporates other branches of science such as biology, chemistry, and etc. Since it is used almost every day “No one can dispute the importance of the contributions to society made by forensic science; the ability to solve crime is undeniably important” (Hunter 13). Forensic science has given criminal investigation a new edge. “Advances in science have opened the door for more effective evidence discovery, howev...