When violent crimes occur, it may result in bloodshed, this is where bloodstain pattern analysis comes in. Bloodstain Pattern Analysis examines the static aftermath of blood in motion and identifies size, shape, distribution, location of patterns to determine the physical events that occurred. The interpretation of bloodstains patterns can help determine origin of the bloodstain, position of the victim or suspect, direction of travel, impact angles, and reconstruct past events. The most common type of bloodstain pattern is impact patterns. Impact patterns is blood being acted upon by an amount of force. There are different leaves of impact forces: low, medium and high force. Impact patterns can also give you the direction, angle of impact, …show more content…
Blood contains plasma white blood cells and red blood cells. Bloody has a viscosity of 4.4 and 4.7 which is the resistance to flow. More resistance than water but less resistance than honey. Blood accounts for approx. 8 percent of the total weight of the human body 5-6 liters in males and 4-5 liter in females. When blood leaves the body, it is in a liquid form, but for anyone that has had a cut it doesn’t remain liquid for long as it starts to clot. Within a few minutes the blood will clot, forming a dark, shiny gel-like substance the grows more solid over time. This clotting can help determine if the attack was prolonged or that the victim was bleeding for some time after the incident occurred. Blood leaves the body indifferent ways, depending on the type of injury inflicted and the force acted upon the …show more content…
The area of convergence is the relative 2-demensinal height of the of the blood source. This is calculated by selecting individual stains and drawing out a linear path of each stain; where each of these individual stains intersect is the area of convergence. The 3-dementional space where the blood source was located is the area of origin. To calculate area of origin, start with measuring the angle of impact which is the Sin-1(width/height). Don’t measure the whole stain just the ellipse of the stain not including the tail. Once calculating selected individual blood spatter, the examiner tapes a red string next to the stain and uses a protractor to measure out the angle they calculated with the angle of impact formula. Once they measure out the angle they secure the string. Then when the selected stains are measure out it the area of origin, a 3-dimensional model of where the victim was at the
In Blood In Blood Out is a drama directed by Taylor Hackford, and starring Damian Chapa (Miklo), Benjamin Bratt (Paco), and Jesse Borrego (Cruz), produced by Hollywood Pictures. The film was based off everyday life in East Los Angeles, from the 1970’s through the 1980’s. Damian Chapa stars as Miklo in the film, a Mexican-American who wanted to be accepted, not by his skin but for the Mexican within him. Benjamin Bratt (Paco) was the older cousin of Miklo, who learned his lesson throughout the movie and changed his ways. Jesse Borrego (Cruz) is the step-brother of Paco who was a talent artist, who ended up turning to drugs because of back problems caused by a rival gang incident.
There are different types of bloodstain patterns that give a sense of what happened at the scene. The idea is to get a sort of background story from the random blood distribution. The different types of blood can tell us the method an assailant used such as passive blood stains. These stains are made from the drops off a weapon due to gravity. For instance, if an attacker w...
Bloodstain Pattern Analysis is a forensic discipline which, among others, the position of victims can be determined at crime scenes on which blood has been shed. To determine where the blood source was, investigators use a straight-line approximation for the trajectory, ignoring effects of gravity, drag and overestimating the height of the source. We determined how accurately the location of the origin can be estimated when including gravity and drag into the trajectory reconstruction. We created eight bloodstain patterns at one meter distance from the wall. The origin’s location was determined for each pattern with: the straight-line approximation, the method includes gravity, and the method we use includes both gravity and drag. The latter
Red blood cells deliver the oxygen to the muscles and organs of the body.
According to Virtual Medical Centre (2014) the primary function of the blood is to act as a transport, to give the body protection and to help regulate. The blood dissolves gases such as oxygen and carbon dioxide. The blood also transports vital nutrients throughout the body, such as micro-nutrients, fatty acids and amino acids. The flow of the blood helps to regulate the body’s temperature. Also the blood removes wastes material of metabolism. Blood cells (white and red cells) are carried through the body to help with the body’s natural defense, blood clotting and the carry anti-bodies.
Blood serves as the body transport system; blood carries oxygen to the lungs and cells throughout the body. It takes carbon dioxide or toxins from out the body. The components of the blood fight off different diseases by recognizing engulfing microorganisms and molecules from overseas that doctors found in the blood. The other components support the transports through the kidneys, hormones in the body, and the digestive system to help pass the nutrients through the body.
Red blood cells with normal hemoglobin (HbA) move easily through the bloodstream, delivering oxygen to all of the cells of the body. Normal red blood cells are shaped like doughnuts with the centers partially scooped out and are soft and flexible.
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
Bloodstain pattern analysis (BPA) is one of many specialties in the field of forensic science; the science of bloodstain pattern analysis use scientific knowledge from other fields to solve problems. BPA also uses the scientific method to examine bloodstain evidence at a crime scene where blood is present by gathering information, observing, documenting, analyzing, evaluating, and technical or peer reviewing. A bloodstain pattern analysis job is to collect, categorize and interpret the shape and distribution of bloodstains within a crime scene (Peschel, 2011). Bloodstain patterns can reconstruct a crime scene and then determine the crime as an accident, homicide, or suicide; the blood can also identify the location, quality and intensity of an external force. The purpose of a BPA’s is to determine bloodstain patterns and to recreate the action that caused the blood.
Blood stains are one type of evidence that can be found at a crime scene. Blood that is still in the liquid form should be picked up on a gauze pad. Once the blood is dried thoroughly it should be refrigerated and sent to the Laboratory (Andrus et al., n.d., para. 1). If the blood stain is found dried on clothing, the officer should wrap the piece of clothing in clean paper and place it in a sealed and labeled container. An object with dried blood stains needs to be sent to the Laboratory if it is small enough. If the object is too large to send, then using a clean knife the stain needs to be scraped onto a clean piece of paper, which then can be folded and placed in an envelope (Andrus et al., n.d., para. 2). When collecting autopsy blood samples, the officer should request that the pathologist obtain the sample directly from the heart and place it in a yellow or purple stoppered vacutainer. If the victim is still alive but in serious need of a blood transfusion, then the pre-transfusion blood sample needs to be obtained promptly before the hospital discards it (Andrus et al., n.d., para. 4). It is important for the Laboratory to receive all blood samples within 48 ho...
If blood from a crime scene is not processed or handled correctly, it can weaken or destroy potential source of facts in a case. Blood evidence can also point the investigator in the direction he or she needs to go in order to solve the case (Schiro, 2016). Blood evidence should never by exposed to humidity. It should also be refrigerated until it can be transported to the crime lab. The evidence should be collected in a paper bag, sealed with evidence tape and initialed by the investigator.
The second and more serious type of bleeding is venous bleeding, which transpires when a vein has been severed and blood flows steadily. Most veins collapse when cut, which aids in controlling this type of external bleeding until medical attention can be received.
In here I will clarify each potential evidences of the crime and explain of the application of the identified forensic procedure to the facts of the case. One of the perpetrators cuts his hand when trying to drag of the witness in the crime scene. Thus, in this case blood stains would be the one of the potential evidence. The precipitin test might be applied to bloodstains in a numerous ways. It conduct...
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.
I will be investigating Human Blood as my specific tissue and giving an overview on the location, characteristics, and the benefits it has to the human body. Blood is extracellular matrix that is consists of plasma, red blood cells, platelets, and white blood cells. Blood is located within the capillaries/veins/arteries of the human body, which are blood vessels that run through the entire body. These blood vessels allow the blood to flow smoothly and quickly from the heart to distinct parts of the human body. The unique parts of human blood all work together for a purpose: the Red Blood Cells(erythrocytes) transports oxygen throughout the body, White Blood Cells(leukocytes) play a part in the bodies immune system, Platelets(thrombocytes) assist in creating scabs,