PPT-The Science of Blood Spatter

Spatter Definition What is impact spatter A blood stain produced when an object makes forceful contact with a source of blood projecting blood outward from the source Why do we care Why is impact spatter important. Blood spatter . 1939—spatter . patterns first . analyzed. Blood may . spatter . when a wound is inflicted. Blood . spatter . pattern—a grouping of blood stains. Patterns help to reconstruct the events surrounding a shooting, stabbing, or beating. Bloodstain Science . What . does the abbreviation BPA represent? . Bloodstain Pattern Analysis. What can an investigator learn from the analysis of a blood spatter?.  Type and velocity of weapon. The success or failure of any criminal investigation often depends on the recognition of physical evidence left at a crime scene and the proper analysis of that evidence.. Crime scenes that involve bloodshed often contain a wealth of information in the form of bloodstains.  The pattern, size, shape, and the location of such stains may be very useful in the reconstruction of the events that occurred. . Griffin. Bloodstain patterns. The patterns left by falling, projected, or smeared blood can help the forensic investigator interpret and reconstruct what has happened at a crime scene.. Observation of the position and shape of stain patterns can give information such as:. Chapter 8. Blood Spatter . #1…it’s not “. splatter. ”! . . Properties of blood affect pattern:. Fairly . high surface . tension (cohesion). Very . viscous. Sticky-adheres . to external . surface (adhesion). Ms. Schultz. The Sam Sheppard Case. On July 4, 1954 Sam Sheppard called police to report that his wife Marilynn was dead in the bedroom. He said the night before, his wife had gone upstairs to bed while he was asleep on the couch. When he went upstairs, he saw his wife covered in blood. He heard a noise and ran downstairs chasing after a 6’3’’ bushy haired man. The two struggled and Dr. Sheppard was choked unconscious. When police arrived, Marilynn was found with 35 wounds to the head and blood drenched the walls, door, and bed. Her face was almost unrecognizable. Sheppard served 10 years in prison before the US Supreme court rules that the trial had been tainted. The evidence was reexamined. Blood spatters and blood drops provided some of the most compelling evidence. Dr. Paul Kirk, an expert in blood analysis, determined the killer could not have been Sam because the attack was perpetrated by a left handed person. Dr. Sheppard was right handed.. Bits and pieces…. Use of force to describe the blood spatter. In the past, forensic investigators used ‘velocity’ to describe a pattern of blood dispersion. . Low . velocity (gravity/drop, 5ft/s) . Class Starter: . What are the different blood types that exist?. What determines what type of blood you have?. Why can you die if you were to receive an incompatible blood type?. What determines the different blood groups?. 1. What type of bloodstain?. 2. What type of blood stain?. 3. What type of blood stain?. 4. . . What type of blood stain?. 5. What type of blood stain?. 6. What type of blood stain?. 7. type of blood stain?. October . 14, 2014. Points of origin and convergence. The source of blood spatter can be localized by following the direction of travel of several stains.. Direction of trave. l . The narrow end of an elongated . SFS1. Students will recognize and classify various types of evidence in relation to the definition and scope of Forensic Science.. SFS2. Students will use various scientific techniques to analyze physical and trace evidence.. Blood Stain Evidence. Bloodstain patterns can help investigators reconstruct events in a crime scene.. Analysis of the blood stain can tell whether it is animal or human.. Projected blood stains are called . Blood vessels that carry blood from the heart The tiniest blood vessels Parts of the respiratory system SFS3 Students . will analyze the use of toxicology, . serology. , and DNA . technology in . forensic investigations. . d. . Differentiate the forensic techniques used to distinguish human and . animal .