The bloodstain pattern analysis plays a very important role in the reconstruction of many crime scenes. Each analyst is expected to use their training, experience and education to support conclusions, opinions and interpretations. Bloodstains in a crime scene provides important clues as to the victims movements at the time of an assault, and movement of the persons body. Perhaps, my favorite subject in all of forensic science. Test your bloodstain analysis skills 25 february 2009 bloodstain analysts claim to be able to identify how a bloodstain was created simply by looking at it. An expert in blood spatter took the stand monday in the second week of brittany norwoods trial in the killing of her coworker at a bethesda yoga store. The type of surface that free falling blood strikes affects the appearance of the resulting spatter. Letters denote a significant p books many fascinating stories and analysis, despite being one of americas leading instructors in blood but not because the book isnt interesting and informative, but because the stories reflect genuine breakthroughs in blood spatter analysis as opposed to murder porn. Rather, blood spatter is most often used as a tool to support or refute eyewitness testimony. They take notes, sketch, photograph, and video tape the patterns.
The pattern of the blood that is spattered around the crime scene, called the bloodstain pattern, contains valuable information about the sequence of events that occurred to cause the victims injuries. Unlocking this information requires the expertise of a forensic scientist who specializes in. For over 50 years, crime investigators have been playing a grisly game of connect the dots, linking blood spatter at violent crime scenes to ruthless killers. Blood may be dripped out of the body, sprayed from an artery, oozed out through a large wound or flung off a weapon that has struck another person. Engineer working to put more science behind bloodstain. Wear goggles to protect your eyes from splashing liquids. Bloodstain pattern analysis bpa is the study and analysis of bloodstains at a known or suspected crime scene with the purpose of drawing conclusions about the nature, timing and other details of the crime.
Blood spatter is often the most important and crucial piece of evidence at the scene of a crime. Its about analyzing the trajectory, size, and pattern of blood, but what is it called. Aim hypothesis variables method results conclusion discussion background research my hypothesis. As a research guide, blood spatter presents an accurate and accessible gateway into the world of blood spatter and its analysis. For example, if a victim was punched low velocity blood spatter, then stabbed in an artery medium velocity blood spatter, and then shot high velocity blood spatter, a surface would have a blood stain with three distinct layers. Ncjrs abstract national criminal justice reference service. The various types of bloodstains account for how the blood was projected from the body. Blood spatters are when blood drops hit the surface at hand at a certain angle creating a splat in a certain shape. Theory and practice presents an indepth investigation of this important subject matter. Of course, analyzing blood spatter isnt as simple as fictional bloodstain pattern analysts like dexter morgan make it appear. The interpretation of blood spatter may not always be definitive. Finally, blood spatter overlap occurs when blood was deposited onto a surface in a specific order freeman, 2008. Uncertainties associated with bloodstainpattern analysis.
Blood splatter analysis blood spatter analysis kenisha callahan ajs 592 dr. Introduction becausebloodbehavesaccordingtocertainscientificprinciples,trained bloodstainpatternanalystscanexaminetheblood. Throughout the case, the local police improperly handled blood spatter and other evidence. Although the term blood spatter may evoke some provocative images, blood spatter analysis is a specialty rooted in details, sometimes involving very little blood at all. Safety precautions and materials questions and answers precautions. Analysts examine subtle factors such as the placement, shape and volume of blood to determine the weapon and amount of force used in an attack. This test method is a general approach to the examination of bloodstain pattern analysis. The assessment of the diameter and shape of bloodstains, which reflect the origin and trajectory of external blood flow, in the context of homicide or violent death. Here is some information about blood spatter analysis that is used in crime scene investigation, and back at the lab during the analysis. The following is the data analysis of the experiment done in order to find the answer to the questions above. Blood reacts, as all liquids do, in a predictable, consistent, reproducible manner.
A bloodspatter analysis by the missouri state highway patrol led to the conviction of brad jennings in 2009. Pull back long hair into a ponytail in order to hair out your face and out of the experiment. While blood spatter analysis can be extremely effective in determining the placement of perpetrators, victims, and weapons during the course of a violent crime, rarely are blood spatter analysts called on to make these assertions on their own. See more ideas about forensics, forensic science and forensic anthropology. Later analysis revealed that the stains came from a spilled drink and a sounddeadening compound that came with the car. The type of surface that free falling blood strikes affects the appearance of the resulting splatter. Blood stain pattern information is gathered at the crime scene by the forensic identification unit. Test your bloodstain analysis skills new scientist.
The dimension and formation of blood spatter can depend on certain factors. Scientific studies support some aspects of bloodstain pattern analysis, the report says. Blood drops on a smooth surface will make a more uniform or regular circular shape. Further validation of the backtrack computer program for. Some error rates associated with bloodstain pattern analysis. Blood spatter analysts provide an extremely important service in specific areas of law enforcement, particularly those departments that deal with homicide and violent crime. Blood spatter analysis can be vital in understanding the incident and solving the crime. Wear gloves to prevent staining hands with dye and protect. It is important that first responding officers at crime scenes understand the importance of blood spatter evidence and properly measure and photograph that evidence for blood spatter experts to analyze. Guidance on the requirements of bloodstain pattern analysis.
Forensics investigators found blood stains in the family car and concluded that lindy had taken azaria there to cut her throat. Instead, many wrongful convictionswhether due to faulty bloodspatter analysis, misread fingerprint matches, shoddy lab analysis, or junk arson sciencedisappear into the shuffle of the. About bloodstain pattern analysis the science of dexter. The distance from which blood falls correlates to the size of the blood spatter produced in a direct relationship the higher the fall, the larger the spatter. Bloodspatter expert testifies in yoga store killing the. Join two investigations and see how the everevolving forensic science of bloodstain pattern analysis helped investigators solve both the 1954 murder of the wife of a prominent doctor and. These are the three main categories of bloodstain pattern. How bloodstain pattern analysis works howstuffworks. Steven gilbert blood spatter analysis blood spatter analysis is the systematic assessment of the visual patterns of bloodstains at crime scenes based on the physics of fluids brodbeck, 2012, p.
It is one of the several specialties of forensic science the use of bloodstains as evidence is not new. Experts in the field often say that its as much an art as a science. A multidisciplinary approach is presented throughout the book that uses scene and laboratory examinations in conjunction with forensic pathology, forensic serology, and chemical enhancement techniques. If you are interested in forensic science and maybe want to be a csi one day, youre in the right place im here to help. Bloodstains analysis is the examination of the shapes, locations, and distribution of patterns of bloodstains, in order to provide an interpretation of the physical events that gave rise to their. However, since the late 1950s, bpa experts have claimed to be able to use biology. Although important aspects of bloodstain pattern analysis are well supported by research, analysts must be careful not to overreach source. Everyone who has studied the topic knows there is a debate on whether it is called blood splatter analysis or blood spatter analysis. One can tell, for example, if the blood spattered quickly or slowly, but some experts extrapolate far. Written as a resource for the professional author, this forensics for fiction title provides userfriendly approaches to realistic details by covering. Blood spatter analysis definition of blood spatter.
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