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Click www.ondix.com to visit our student-to-student file sharing network. One of the most essential part of crime scene investigation are the part of a criminalist. He is a partner of an investigation process that finds bits and pieces that even some investigators don't see. Crime scene personnel can encounter blood evidence in many types of cases, including burglaries and other non-violent crimes, but it is most often encountered in crimes of violence such as homicide, assault, and sexual assault. Bloodstain patterns are one of the most intriguing parts of forensic science that has become more recognized today as not just a science but an art as well. The examination of blood provides invaluable information to the forensic scientist in many areas of criminal investigation. It determines whether or not if this was a violent crime, accident, suicide, or natural death. Blood is the most significant and frequently encountered types of physical evidence associated with forensic investigation of death and violent crimes. Crime scene reconstruction demands that we evaluate all physical and testimonial evidence to derive some conclusions as to what occurred. The goal of bloodstain interpretation is to reconstruct the crime scene utilizing the bloodstain patterns in answering our questions whether the crime, which was committed, was violent in assisting in forensic investigations. For homicide investigations, case resolution hinges on "careful and intelligent examination of the scene". The nature of the blood spatter determines whether or not this was a violent crime and helps the investigator in reconstructing the crime scene. (Bevel, 2000) Throughout history, bloodstain patterns were not appreciated as a forensic skill in determining how a crime was committed and with what weapon. The first study in blood interpretation was documented by Dr. Eduard Piotrowski in Poland. His work led this art of work into a more useful skill in crime scene investigation and later was introduced into the United States around the twentieth century. One of the first significant cases that recognized bloodstain interpretation as a forensic science which solved many investigations was the case State of Ohio vs. Samuel Sheppard in 1955. Dr. Kirk was able to establish the relative position of the attacker and victim at the time of the administration of the beating. He was also able to determine that the attacker administered blows with the left hand, which was significant because Dr. Sheppard was right handed. (James " Eckert, 1998) In 1982, further study and research was done by MacDonnell who organized and researched bloodstain interpretation through training to police agencies and criminalists. This lead to the art of bloodstain interpretation in forensic science which increased considerably and today many are still contributing to this field of study. Today, one of the biggest organization is the Advanced Bloodstain Institute held in New York and holds around 300-350 members throughout the World. This organization trains, explores, and researches basic courses for bloodstain interpretation. Bloodstain pattern interpretation is a discipline which involves many other fields of study such as biology, physics, and mathematics. It is studied through the photographs, clothing, weapons, or other objects regarding physical evidence. What is blood spatter? And how do drops of blood play a role in crime scene investigation? Actually, it is called Bloodstain Pattern Interpretation. It involves reconstructing the events that must have happened to produce the bleeding. It is not something that most law enforcement officials can do--it usually requires a specialist. The first step when dealing with blood in any aspect of forensics/criminology is to know the characterization of bloodstains. (Gutierrez, 2002) Blood can be characterized as a fluid substance that circulates in the arteries and veins of the body. Blood is bright red or scarlet when it has been oxygenated in the lungs and passes into the arteries; it becomes bluish red when it has given up its oxygen to nourish the tissues of the body and is returning to the lungs through the veins and the tiny vessels called capillaries. Blood consists approx. 8% of the total human body weight. Blood is composed of a yellowish fluid, called plasma, in which are suspended the millions of cells that constitute about 45 percent by volume of whole blood. It has a characteristic odor and a specific gravity between 1.056 and 1.066. Bloodstains results from exposed blood that has come in contact with external surfaces in the environment as a result of a bloodshed event. (Fisher, 1981) When the circulatory system is disrupted by trauma or disease, bloodshed occurs internally, externally or even both. Bloodstains are characterized by their appearance on the various surfaces that the blood contacts subsequent to bloodshed. The application of the physical properties of bloodstains determines the basis for the study and interpretation of the location, shape, size, and direction of bloodstains relative to the force of gravity. External forces can act upon exposed blood, overcome these physical properties and create a variety of blood formations, droplets, or spatters. They have been grouped into three main categories: low- velocity, medium-velocity, and high -velocity impacts. (James, 1999) The basic premise deals with the impact energy that is categorized into low, medium, and high impact spatter. (Moore, 2002) Low velocity impacts are characterized by external force applied to the blood source of up to 5ft. typical size of a bloodstain is 3mm in diameter. Examples of low- velocity bloodstains are blood drops, splashed and projected blood, or free-falling blood drops. Free falling blood drops can drip from clothing, hair, weapons, or any object which can be determined if the person stood there after killing his victim or violently killed its victim. The angle of impact is defined as the internal angle at which blood strikes a target surface. The angle of impact is a function of the relationship between the width and length of the bloodstain. (Eckert, 1997). Free falling blood drops that fall vertically onto a horizontal surface impact at 90 degrees. The resultant bloodstains are essentially circular in shape on a smooth hard surface. These drip patterns will be large and irregular in shape with small circular forms. A projected bloodstain pattern is a result of a rapid movement with when excessive blood is projected as the result of force. For example, throwing up blood is projected blood in large amounts. (Bevel " Gardner, 2001) Blood droplets may strike a surface at any series of angles and directions. The tail of a bloodstain generally point in the direction the blood droplet has traveled. When a blood source is subjected to a force or impact, the resultant blood droplets may strike a target surface at various angles and directions. A point of convergence is defined as a point to which an individual bloodstain pattern can be traced or projected on a surface. This is defined by tracing the route of the bloodstains to a common point or points. For example, in the movie, it demonstrated using this method by using straws or strings to give the direction and point of convergence of the bloodstains and reconstruct the crime scene in order to determine if the cops were the first shooters or not. (Lee " Harris, 2000) Medium-velocity impacts are characterized by external force applied to the blood source between 5-100ft. The typical sizes of these bloodstains are between 1-3mm in diameter although larger or smaller stains can be present. Examples of medium-velocity bloodstains are beating with hammers, bricks, baseball bats, etc.. When these types of bloodstain patterns are projected, they are distinguishable from low velocity bloodstains. Medium velocity bloodstains consists of stains produced on a surface when the blood source has been subjected to a force at a velocity. The energy of the impact causes the blood to be broken up into small droplets such as coughing up blood, or minor incidents such as slapping of a hand or object in blood. The occurrence of these events can often be recognized and distinguished through careful examination of the entire crime scene, the victim's injuries, and condition of the body. (Eckert, 1998) Impact velocities associated with beatings and stabbings falls within this category. Blows administered to a victim with sharp instruments will produce medium velocity blood spatter that may be differentiate from high velocity spatters. High-velocity impacts are characterized by external force applied to the blood source of greater than 100ft. The typical size of bloodstains produced is less than 1mm diameter although larger or smaller stains may appear. Examples of high-velocity impacts are gunshot trauma, explosions, or machinery trauma. Acts of extreme violence often produce a dispersion of blood volumes forced from a wound site Gunshot and other high energy impacts such as blunt force or gunshot wounds, may disperse these blood volumes along relatively flat trajectories. (Moore, 2002) Blood is very uniform and reacts in predictable, consistent and reproducible manners when impacted. Therefore, blood forced out entry and exit wounds is disbursed in a prescribed manner. These are blood spatters from the victim's entrance and exit wounds and are based on forward spatter and backward spatter. Back spatter is directed from the back of the weapon and can be deposited on the skin or clothing. The amount of back spatter is also affected by the type of weapon and ammunition and the anatomic features of the wound site. Forward spatter is produced by blood droplets traveling in the same direction as the source of energy and, in gunshot cases; it's associated with the exit wounds. The bloodstain interpretations have been helpful in identifying whether or not it was a violent death or something else. (Eckert " James, 1998) In the cases of violent death, the external examination of the victim prior to the autopsy by a forensic pathologist can reveal bloodstain patterns and changes within the body. For example, if there are bruises on the skin that have an object shape than we can determine with what object was used and how they struck the victim. The degree of postmortem lividity or settling of blood within the body may help establish the approximate time of death or whether the lividity is consistent with the position of the victim at the scene. (The value of videotaping blood evidence is that the overall relationship of various blood spatters and patterns can be demonstrated. One example of this could be a beating homicide. (Lee " Harris, 2000) In this case, videotape can show the overall blood spatter patterns and how these spatters are inter-related. The videotape can also show the relationship of the spatters to the various structures at the crime scene. In cases where the suspect may have been injured (such as stabbing homicides), the video camera can be used to document any blood trails that may lead away from the scene. (Adams " Krutisinger, 2000) One of the important parts of bloodstain interpretation is the documenting, collecting, and evaluation. Initial bloodstain evaluation at a crime scene should be able to provide the investigator with the general nature of the activities that took place and relative movements of victim and assailant. (James " Eckert, 1998) Crime scene areas are documented either by photographs or videotapes. Videotapes can be an excellent medium for documenting bloodstains at a crime scene. This is to record the evidence before any major alterations have occurred at the scene. Videotape provides a perspective on the crime scene layout that cannot be as easily perceived in photographs and sketches. It is a more natural viewing medium to which people can readily relate, especially in demonstrating the structure of the crime scene and how the evidence relates to those structures. (Adams " Krutsinger, 2000) The identification of blood and forensic serological studies for grouping and interpretation of bloodstain spatters depends on the DNA make-up and genetic marker. (Lee " Harris, 2000) Investigators must first remove bloodstained objects from the crime scene for the submission to the laboratory. Once they reach the laboratory, scientists group them together and run some ABO grouping tests to determine the age of the blood, the quantity of the blood available, and environmental conditions to which the blood has been exposed. Blood of the victim's ABO or enzyme type on suspect's clothing can prove an invaluable link between the victim, crime, and perpetrator. A Forensic serologist examines the blood left at the crime scene he then tries to distinguish it from human to animal blood. Once this process is done, the serologist analysis it and groups it according to its ABO group. The results are then compared to the victim's blood and suspect's blood. (James, 1999) In collecting bloodstains, if the bloodstain object can't be moved, the stains can be collected onto swabs or cotton threads. The evaluation of bloodstains on clothing, objects such as knives or handguns, or walls can tell a lot about this person and helps to establish the involvement with the assault on the victim whether it was violent or not. The careful examination of bloodstained clothing and footwear often provides valuable information for accurate reconstruction of a violent crime. Bloodstain patterns on the victim's and assailants clothing determines the position and movement during an attack or struggle after blood has been shed. (James " Eckert, 1998) Bloodstain patterns on a suspects clothing will confirm or refute explanations offered by the suspect concerning the reason for his bloodstain clothes. (Lee " Harris, 2000) If we can't find blood at the crime scene, we can detect blood through a process called luminal. It produces a bright luminescence when in the presence of different amounts of blood. It is a valuable tool for the investigator since it not only discloses the presence of blood but its distribution. Luminol's reaction with a bloodstain spatter produces an intense glow in many different patterns such as spatters, smears, or wipes. This test has been debated because it reacts with many different chemicals such as house cleaners or something in the substrate. (Fisher, 1981) Usually if there is no presence of blood, chances are that criminalists will use luminal to determine where blood is present. For an example, one case study showed where a woman was on her way home to change to go out with a friend and the next day she was reported missing. Investigators found no traces of blood in the victim's trailer home and her husband was known for marital abuse. Once they lit the trailer with luminal blood was found on the couch and all over clothes. The husband was found guilty of murdering his wife and luminal demonstrated that the bloodstains had been cleaned up linking the husband to the crime. The luminol test works best to discover an area where an attempt has been made to clean up blood. Research has found that luminal is a successful reagent and, by using this method, investigators has solved more cases by using luminal process. (Fisher,1981) Blood analysis is very important in many different situations. For example, in forensics, if a bloodstain pattern is obtained, analysis is vital. BPA (Bloodstain Pattern Analysis) may on many occasions, clearly define the location of the victim or the assailant by establishing the actions of either or both. All individual bloodstains which have resulted from blood drop distribution are called spatter patterns. Although spatter patterns are often emphasized over other bloodstains, they essentially involve class characteristics. Class characteristics are those features which identify or separate other group from other classes. (Wonder, 2001) Possible and impossible scenarios may be established to determine if the victim, witness, or assailant is accurately describing what took place. Numerous courts throughout the country have upheld the value and scientific reliability of BPA. Court case information is available upon request. BPA is a valuable asset during and after the initial investigation. BPA has been extremely valuable during the establishment of the courtroom trial strategy. (Bevel " Gardner, 2001) Case study shows how bloodstain pattern interpretation has solved many cases in determining if these crimes are violent or not. Police were called to the scene of a fatal shooting of young black man which occurred in the residence of his girlfriend. The cause of death was a gunshot wound with the entrance wound located in the left posterior parietal scalp in the kitchen. Investigators determined one of his drug deals went bad but further investigated the bloodstain patterns and determined that small spatters of blood in size range of medium to high velocity impact blood spatters was created by events other than gunshot. (Eckert, 1998) Another famous case in which successfully used bloodstain evidence is the case of the State of Ohio vs. Samuel Sheppard. It was a famous case in which Houk had checked on Marilyn Sheppard in her room and discovered there were blood spatters all over the walls and police discovered she had suffered thirty-five blows to the head by some blunt instrument causing her death. The murder of Marilyn Sheppard captivated the attention of news media in an unprecedented manner and on December 21st, verdict was guilty to second degree murder. This case opened a lot of interesting research in the blood analysis field and it became more respected for its use. (Gutierrez, 2002) One popular case study in regards to bloodstain pattern interpretation was the case a New York City homicide case was investigated at the request of the District Attorney's office. The deceased had been violently beaten about the face, neck, and chest area. The bludgeoning left the victim unrecognizable, and produced bloodspatter patterns at the scene that attained heights over nine feet. The suspect claimed that he reacted in selfdefense to the victim's attack with a table leg at which point he "knocked him down" and possibly "kicked him a few times." Our investigation was intended to determine whether the blood spatter patterns observed at the crime scene were consistent with the statements made by the defendant. Conclusions were drawn from an analysis of the crime scene, autopsy photos and report, physical evidence submitted to the laboratory, and reconstruction experimentation performed at the Office of Chief Medical Examiner (OCME). The spatter patterns observed at the scene were found to be consistent with those that would be produced from a "stomping" incident. (Ristenbatt, 1995) Bloodstain pattern analysis has made a notable contribution to the scientific investigation of violent crime scenes by assisting with the reconstruction of the event in which blood was shed. Since it is accepted in courts throughout the nation, analysis of bloodstain patterns on crime scenes is routinely used by law enforcement. Both international and U.S. based professional organizations recognize bloodstain evidence analysis techniques as a valid investigative tool. Bibliography http://www.letsfindout.com "Blood Type" - Encarta Encyclopedia "Forensics"- Encarta Encyclopedia Adams, Thomas F " Krutsinger, Jeffery L. Crime scene investigation. Prentice Hall Publishing. 2000 Bevel and Gardner. Bloodstain pattern analysis: With an introduction to crime scene reconstruction. CRC Press. 2001 Fisher, Barry. Techniques of Crime Scene investigation. Elsevier Science Publishers. Third edition. 1981 Gutierrez, Sherry. Bloodstain Pattern Analysis. Journal of forensic sciences. www.jfklancerforum.com 2002 James, Stuart " Eckert, William. Interpretation of bloodstain evidence at crime scenes. CRC press. 1998 James, Stuart. Scientific and Legal applications of bloodstain pattern interpretation. CRC press. 1999. Lee, Henry " Harris, Howard. Physical Evidence in forensic science. Lawyers and Judges Publishing Co. 2000 Moore, Craig. Three-Dimensional models for bloodstain pattern analysis. Journal of Forensic. Identification. 2002 Ristenbatt RR. A bloodstain pattern interpretation in a homicide case involving an apparent "stomping". Journal of Forensic sciences. 1995 Wonder, A.Y. Blood dynamics. Academic Press. 2001 Keywords: most essential part crime scene investigation part criminalist partner investigation process that finds bits pieces that even some investigators crime scene personnel encounter blood evidence many types cases including burglaries other violent crimes most often encountered crimes violence such homicide assault sexual assault bloodstain patterns most intriguing parts forensic science that become more recognized today just science well examination blood provides invaluable information forensic scientist many areas criminal investigation determines whether this violent crime accident suicide natural death blood significant frequently encountered types physical evidence associated with forensic death violent crimes scene reconstruction demands evaluate physical testimonial evidence derive some conclusions what occurred goal bloodstain interpretation reconstruct utilizing bloodstain patterns answering questions whether which committed assisting investigations homicide investigations case resolution hinges careful intelligent examination nature spatter determines whether this helps investigator reconstructing bevel throughout history patterns were appreciated skill determining committed with what weapon first study interpretation documented eduard piotrowski poland work this work into more useful skill later introduced into united states around twentieth century first significant cases recognized interpretation science which solved many investigations case state ohio samuel sheppard kirk able establish relative position attacker victim time administration beating also able determine attacker administered blows with left hand which significant because sheppard right handed james eckert further study research done macdonnell organized researched through training police agencies criminalists lead increased considerably today still contributing field study today biggest organization advanced institute held york holds around members throughout world organization trains explores researches basic courses pattern discipline involves other fields such biology physics mathematics studied through photographs clothing weapons other objects regarding physical what spatter drops play role actually called pattern involves reconstructing events must have happened produce bleeding something enforcement officials usually requires specialist first step when dealing aspect forensics criminology know characterization bloodstains gutierrez characterized fluid substance circulates arteries veins body bright scarlet when been oxygenated lungs passes into arteries becomes bluish when given oxygen nourish tissues body returning lungs through veins tiny vessels called capillaries consists approx total human body weight composed yellowish fluid called plasma suspended millions cells constitute about percent volume whole characteristic odor specific gravity between bloodstains results from exposed come contact external surfaces environment result bloodshed event fisher circulatory system disrupted trauma disease bloodshed occurs internally externally even both bloodstains characterized their appearance various surfaces contacts subsequent bloodshed application properties determines basis location shape size direction relative force gravity external forces upon exposed overcome these properties create variety formations droplets spatters they have been grouped three main categories velocity medium velocity high velocity impacts james basic premise deals impact energy categorized medium high impact spatter moore impacts characterized external force applied source typical size diameter examples drops splashed projected free falling drops free falling drip from clothing hair weapons object determined person stood there after killing victim violently killed victim angle impact defined internal angle strikes target surface angle function relationship between width length eckert free falling fall vertically onto horizontal surface degrees resultant essentially circular shape smooth hard surface these drip will large irregular shape small circular forms projected pattern result rapid movement excessive projected result force example throwing large amounts bevel gardner droplets strike series angles directions tail generally point direction droplet traveled source subjected resultant droplets strike target various angles directions point convergence defined point individual traced defined tracing route common points example movie demonstrated using method using straws strings give direction convergence reconstruct order determine cops were shooters harris medium impacts applied source between typical sizes these diameter although larger smaller stains present examples beating hammers bricks baseball bats types they distinguishable from consists stains produced been subjected energy causes broken small such coughing minor incidents slapping hand object occurrence events often recognized distinguished careful examination entire injuries condition eckert velocities associated beatings stabbings falls within category blows administered sharp instruments will produce differentiate high spatters applied greater than typical size produced less than diameter although larger smaller stains appear examples gunshot trauma explosions machinery trauma acts extreme violence often produce dispersion volumes forced wound site gunshot energy blunt gunshot wounds disperse volumes along relatively flat trajectories moore very uniform reacts predictable consistent reproducible manners impacted therefore forced entry exit wounds disbursed prescribed manner spatters entrance exit wounds based forward backward back directed back weapon deposited skin clothing amount back also affected type weapon ammunition anatomic features wound site forward produced traveling same cases associated exit interpretations have helpful identifying death something else james prior autopsy pathologist reveal changes within example there bruises skin object than determine used they struck degree postmortem lividity settling within help establish approximate time lividity consistent position value videotaping overall relationship various demonstrated could beating homicide harris case videotape show overall inter related videotape also show relationship structures where suspect injured stabbing homicides video camera used document trails lead away adams krutisinger important parts documenting collecting evaluation initial evaluation should able provide investigator general nature activities took place relative movements assailant areas documented either photographs videotapes videotapes excellent documenting record before major alterations occurred videotape provides perspective layout cannot easily perceived photographs sketches more natural viewing people readily relate especially demonstrating structure relates those structures adams krutsinger identification serological studies grouping depends make genetic marker harris investigators must remove bloodstained objects submission laboratory once reach laboratory scientists group them together some grouping tests quantity available environmental conditions exposed enzyme type suspect prove invaluable link perpetrator serologist examines left then tries distinguish human animal once process done serologist analysis groups according group results then compared suspect collecting moved collected onto swabs cotton threads evaluation objects knives handguns walls tell about person helps establish involvement assault careful bloodstained footwear provides valuable information accurate reconstruction assailants position movement during attack struggle after shed suspects will confirm refute explanations offered concerning reason clothes find detect process luminal produces bright luminescence presence different amounts valuable tool investigator since only discloses presence distribution luminol reaction produces intense glow different smears wipes test debated because reacts different chemicals house cleaners something substrate fisher usually there presence chances criminalists luminal where present showed where woman home change friend next reported missing investigators found traces trailer home husband known marital abuse once trailer luminal found couch over clothes husband found guilty murdering wife demonstrated cleaned linking husband luminol test works best discover area attempt made clean research successful reagent using method solved fisher analysis very important situations forensics obtained analysis vital occasions clearly define location assailant establishing actions either both individual resulted drop distribution although emphasized over essentially involve class characteristics class characteristics those features identify separate group classes wonder possible impossible scenarios established witness assailant accurately describing took place numerous courts throughout country upheld value scientific reliability court information available upon request valuable asset during after initial extremely during establishment courtroom trial strategy bevel gardner shows solved determining police were fatal shooting young black occurred residence girlfriend cause wound entrance located left posterior parietal scalp kitchen determined drug deals went further investigated determined small range created events another famous successfully used state ohio samuel sheppard famous houk checked marilyn room discovered over walls police discovered suffered thirty five blows head blunt instrument causing murder marilyn captivated attention news media unprecedented manner december verdict guilty second degree murder opened interesting research field became respected gutierrez popular regards york city investigated request district attorney office deceased violently beaten about face neck chest area bludgeoning unrecognizable bloodspatter attained heights nine feet claimed reacted self defense attack table knocked down possibly kicked times intended observed consistent statements made defendant conclusions drawn autopsy photos report submitted laboratory reconstruction experimentation performed office chief medical examiner ocme observed those would stomping incident ristenbatt made notable contribution scientific scenes assisting event shed since accepted courts nation scenes routinely enforcement both international based professional organizations recognize techniques valid investigative tool bibliography http letsfindout type encarta encyclopedia forensics encarta encyclopedia adams thomas krutsinger jeffery prentice hall publishing gardner introduction press barry techniques elsevier publishers third edition gutierrez sherry journal sciences jfklancerforum stuart william scenes press stuart scientific legal applications press henry howard lawyers judges publishing moore craig three dimensional models journal identification ristenbatt involving apparent stomping journal sciences 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