Description Of The 's Exchange Principle

Physical evidence left behind at a crime scene plays a crucial role in reconstructing the events that took place involving the crime. Bloodstain pattern analysis (BPA) is a discipline which utilizes the sciences of biology, physics, and mathematics. Bloodstain interpretation may be accomplished by direct scene evaluation and/or careful study of scene photographs in conjunction with detailed examination of clothing, weapons, and other objects regarded as physical evidence. The location, spreading, and appearance of bloodstains and spatters can be useful for interpreting and reconstructing the events that produced the bleeding. An investigator or bloodstain pattern analyst can decipher from individual bloodstains the direction and angle

Now a day’s evidence can change a person’s life in the blink of an eye. “People were often punished for crimes based on the word of one or two individuals, with little concern given to sorting out the truth of the affair” (Hunter 12). But today a person must be tried and some physical evidence is needed in order for a person to be convicted of a crime.

There are times when certain forms of evidence, such as blood and fingerprints, need to be obtained before the accused has time to destroy them (Inabau 2).

In the United States, crimes are constantly being committed. Some of the crimes that are committed are simple, and other crimes are extremely complex. Every complex crime comes with its own challenges in distinguishing material evidence. Some evidence can be tiny as a hair, or a fiber that can be located on a piece of clothing or carpet. Even though, the size of the evidence is not important, the information that it provides investigators is crucial to finding the suspect of the crime. With the assistance of trace evidence, investigators can obtain the small particles that can transfer from two objects come together. Collecting material from any crime scene can yield a plethora of information. However, by properly collecting material evidence like the tire print impression, pubic hairs, multiple dog hairs, and foreign fibers. Investigators, were able to convict Cecil Sutherland for kidnapping, sexual assault, and three counts of murder.

The person’s belonging that are obtain from the crime scene should be labeled, dated, and individually identified. The evidence now can be properly identified throughout the process. Law enforcement has rules and regulations to obey at the time of seizing evidence. Nevertheless, if the boundaries are overstepped, there may be room for the evidence to be inadmissible. Seizing evidence is always a great opportunity to place a guilty person away; however, protecting the individual rights are just as important.

Sneakers have been a part of human society for many decades. They are used on a daily bases by ordinary citizens, industrial workers, and athletes. One of the key parts of a shoe is the outsole, the layer that is in direct contact with surfaces. Ancient civilizations adapted the outsoles of their “sneakers” to their environment. Modern day sneaker companies determine the material and texture of their outsoles by examining the way their target consumers will use the product and by using the science of friction.

“If she boiled water the night before, stayed in the bathroom and pretended to shower, once the kettle whistled, I’m sure anyone idiot would run to turn the stove off and end up leaving fingerprints.” Detective Licht place his hands on the table and leaned his weight forward. “She knew every routine and habit of his, so she knew he would be unconscious the whole morning after a long night of drinking.”

The main provision in all cases is the avoidance of including fingerprints to evidence, or of ruining the ones already existing at the time. Once the crime scene has been carefully recorded and each of the evidence located have been annotated, then the process of gathering and analyzing can commence. The crime scene investigator will start by collecting the most delicate and easily prone to be lost evidence. Locating latent fingerprints at the crime scene requires use of techniques that makes it ideal for visibility. Investigators will use a several of methods to visualize the print, however it will depend on the surface that print is being lifted from. All non-movable and fixed items at a crime scene sustained to be handled on the scene using one of

Trace or transfer evidence can be any small, and to the untrained be a seemingly insignificant piece of material, whether man-made or natural, that has been left at a crime scene. Edmond Locard, founder of the Institute of Criminalistics at the University of Lyon, France, developed what has become known as Locard’s Exchange Principle. This states that every contact leaves a trace (Trace Evidence). Trace evidence can consist of just about anything. Some types of trace evidence include but are not limited to hair, blood and other body fluids, paint, glass, and residues. Throughout the years, trace evidence has become very important in the conviction and even the exoneration of those accused of certain crimes.

Davon Morin Bio113 Jill Bigos, M.S. 22 February 2016 Tool Mark analysis Toolmark analysis is a very important part of forensic science. Toolmarks are defined by encyclopedia.com as, “an impression left by the contact of a tool (or a similar object) onto a surface.” Toolmark analysis is pivotal to burglary cases because they can help identify criminals. When a burglar uses a pry bar to force their way into a house, the marks left by the tool on the door frame is evidence of the presence of that tool for use at the crime scene.

If the suspect’s DNA is in a database, a sample of the blood can be swabbed and tested to reveal their identity. The handprint and hammer may have a fingerprint sample that may also help identify them, using fingerprinting tools and a computerized fingerprint database. Shoeprints can help reveal the size and type of footwear worn by the suspect. Cameras and a ruler can be used to photograph the shoeprint and provide a picture of the actual size of the suspect’s footwear.

In the forensic science field, “A Latent Print is an impression of the friction ridge skin of the fingers or palms of the hands that has been transferred to another surface.” To break apart the phrase, “latent print”, the term “latent”, means “hidden” and the term “print” means “an indentation or mark left on a surface or soft substance by pressure especially that of a foot or hand.” So the phrase “latent prints”, refers to any print that must be enhanced chemically or physically to be made visible. Another way to define “latent print”, is simply sweat that is exuded from the body. Friction ridge skin is the only part of the body that doesn’t exude oil. The only oil that may be in a latent print has been picked up by touching another area of the body (face or ears for example) or some foreign object.”

Forensic science involves the use of science to solve criminal and civil crimes but mostly lies on the side of criminal investigations. It makes it possible to identify the criminals based on the DNA traces they leave behind. It involves analyses of blood, DNA and other evidences and later on uses the findings as evidence in the court of law. It helps in solving the various crimes in the world and this has been the greatest contributor to the growth of the sector. Cases that were previously considered impossible due to lack of evidenced tracing to the victim can now be solved using forensic science evidences. The essay aims at analyzing the different aspects of forensic science that are used in the process of solving criminal activities. It will also look at the different cases that forensic science was used to solve crimes in a court of law.

People who enter the scene must be noted, where they went into an area of a scene, and also when they left the scene. Protecting physical evidence for a criminal procedure is another step that is important in helping its success. Packaging is a key role in protecting evidence if it must be collected. Keeping items in separate containers can help evidence from coming in contact with each other and contaminating one another. When picking up items it is important for the collector to wear gloves and use forceps or tools that are similar to pick them up. When picking up DNA, such as, hair fibers, glass, or trace of evidence, the collector must make sure the item is contained in a secure, closed lid container. When storing materials with DNA, such as blood or salvia, it should be allowed to air-dry before being packaged, because it could grow mold and destroy the evidence. The main concern about physical evidence is making sure that it does not become contaminated and the collector must wear disposable clothes, wear gloves, and may also wear eye protection to ensure evidence is not

Marks found on the floor of the crime scene showed particular features which might have resulted from damage to the trainers. As the trainers recovered from the appellant didn’t show any of the above features, following explanations were provided which would not exclude the possibility that the marks had been made by the trainers:-