Blood Spatter in Crime Scene Investigation
Blood Spatter in Crime Scene Investigation
Checking all aspects of a crime scene is a crucial part of investigating a crime. The thorough sampling of all suspicious items in a crime scene, like footsteps, hair strands, and even the changes that took place in the pieces of furniture may help in leading the authorities to the doer of the crime. Oftentimes, even the way the blood splattered from the victim to the walls and floors of the crime scene can help pave the way to the solution of the crime. Blood may be like any other piece of evidence in a crime scene. It is what everyone else immediately sees.
It does not talk, yet it can tell so much information. Through analysis of blood splatter, an investigator can tell how the person was killed and from what angle it was done. It can also tell whether the act done fast or as slowly as possible. Blood splatter can greatly help in crime investigation through the analysis of it. Human Blood Normally, the human blood comprises seven to eight percent of the body weight. It carries the essential functions of carrying oxygen and nutrients to the body cells. It also rids the body of carbon dioxide, ammonia, and other body wastes.
The blood also serves an important role in the body’s immune system and in maintenance of the body temperature. It is a specialized tissue that has various components. It is a four to six quarts tissue with many components being pumped throughout the body. It circulates constantly in the body, making everything function normally. This is the reason why, when this circulation is disrupted by any action, it spatters (O ‘Neil, 2008). There are various ways that can greatly disrupt the circulation of the blood. Definitely, the most disturbing are violent confrontations like, bullet-shot trauma, blunt force trauma, or knife trauma.
The effects of these acts on the blood may vary into two. It can either spill or the blood may spurt out of the body into scattered drops. These differences in the effects of action to blood can help tell the forensic experts of what truly happened in the crime and to the victim (Castillo, 2009). Blood Spatters and the Crime Scene The positions of the blood stains or the patterns of the blood can greatly help in the solving of crimes. As was mentioned, there are numerous ways in which blood may come out from the body once a violent act is done to disturb the circulation.
Through these various effects on the blood spatters, forensic scientist are able to conclude what really took place in the scene. Blood spatter normally tell the experts five important and oftentimes incriminating pieces of information about the crime. The positions of the blood spatters tell first, the activity at the scene. Second is the number of blows the victim received from the suspect or suspects. Third is the position of the victim and the assailant within the crime scene. Fourth is whether the death of victim was immediate or delayed.
The fifth and last things that blood spatters tell are the characteristics of the weapon utilized by the assailant in attacking the victim (Waldrip, 2008). There a number of ways to analyze a blood spatter pattern. Given a room where blood is all over the wall, a person may conclude that the traumatic attack have been done all over the room. However, carefully following the rules on blood spatter analysis, forensics will definitely disagree. One way of knowing this fact is through the string convergence analysis. The string analysis is a common means of analyzing blood spatters.
It utilizes strings that are attached to the points where blood has dropped. For instance, on a wall filled with blood droplets, an end of a string is pasted while the other end is pasted on another wall with a droplet. This is done with each remaining blood droplet all over the crime scene. If looked at by ordinary people, the pattern that will be formed by this activity may mean nothing. It will only look like a web created from a ball of yarn of string. However, for forensic experts, doing this will immediately tell them what they need to know (Carter, 2009).
The pattern that was formed from the strings may look like a cobweb in the eyes of ordinary people, but to forensic experts, it already told the position where the victim was attacked. If observed carefully, the strings which were connected always meet in one area. The intersection or convergence point of all strings is the exact position of the victim when the attack occurred. From this, any lie or alibi given in relation to the position of the body will immediately be dismissed. The blood spatters unlike men, can not lie. As such, it is commonly believed more by judges and jurors (Carter, 2009).
After the position of the victim is found, another form of blood analysis is done. The distance of the blood from victim is then measured. The measurement that is acquired from the distance always corresponds to a certain spatter velocity. This velocity also corresponds to a certain type of attack done to the victim (Waldrip, 2008). Low velocity blood spatter is typically indicated by five feet per second and three millimeter diameter and is usually dripping. Medium velocity blood spatter is on the other hand, indicated by five to twenty-five feet per second with less than three millimeter diameter.
This type of velocity is commonly caused by blunt force trauma or sharp pr knife trauma. The third type of velocity is the high velocity spatter, which is more than one hundred feet per second with a spatter of less than one millimeter. This is indicative of gunshot trauma, power tools, and objects striking with extreme velocity or an explosion (Waldrip, 2008). Through the analysis of these different velocities of blood spatter, forensic investigators easily learn what the weapon of attack was used (Waldrip, 2008). This helps in identifying the weapon even if the suspect has disguised it, hid it, or completely eliminated it.
This may incriminate the suspect or point the true criminal during litigation. Another use of blood spatter is in telling the angle of the impact of attack. This will point the position of the attacker from the victim and from where his arms began the movement for the attack. The tail of blood spatter is the most important aspect in this analytic strategy (Waldrip, 2008). In this analysis the most important things to look at are the positions of the drops. Drops that are circular are always from vertical positions. This means that the attack and position of the victim is above. This drop is commonly on the floor.
If the blood droplets are on the wall, its elongation should be checked. As the angle increases, the drops usually elongate. This points that there is an existing distance between the attacker and the victim. If the angle is decreased, this may point that the attack was done point blank or in shorter distance from the victim (Waldrip, 2008). Other than these strategies, there still remaining other ways in blood analysis. Sometimes, when the blood flowed freely on the floor of the crime scene, forensics can easily tell that there are objects removed from the crime scene, perhaps by the criminal or accomplices.
When the blood flowed freely on the floor of the scene, the area where there is no blood indicates that there had been an object in that place during the time of attack. The shape that was left by the object may help in locating this object which may be used as evidence against the criminal (Waldrip, 2008). Given these strategies or ways in analyzing blood spatters, it may be said that blood spatters or patterns of blood spills is a crucial part of a crime scene investigation.
The many ways in which the blood patterns in a crime scene may be analyzed helps in deciphering certain information that other pieces of evidence may not be able to tell. Even though blood spatters are hard to look at, looking closely at it may actually help in incriminating the suspect of a crime. Criminals should keep in mind that even though the victims died the blood they leave behind will point out what really took place, where it was done, how exactly it was done and more importantly, who had done it. References Carter, F. (2009). “Blood Spatter Analysis”. Iprimus. com. Retrieved May 3, 2009 from
http://home. iprimus. com. au/ararapaj/craigslea_testbed/Forensic%20Web%20Test%20 Site/blood_spatter_analysis. htm Castillo, F. (2009). “Forensic Blood Spatter Analysis- Stains and Spatter from Blood”. Ezinearticles. com. Retrieved May 3, 2009 from http://ezinearticles. com/? Forensic-Blood-Spatter-Analysis—Stains-And-Spatter- From-Blood&id=934816 O ‘Neil, D. (2008). “Blood Components”. Palomar. edu. Retrieved May 3, 2009 From http://anthro. palomar. edu/blood/default. htm Waldrip, E. (2008). “Blood Spatter Analysis”. Basepairlibrary. com Retrieved May 3, 2009 From http://72. 14. 235. 132/search?
q=cache:SqqvCngUOhAJ:basepair. library. umc. edu/FBL M/BASE%2520PAIR%2520LABS/CSI%2520UMMC/H%2520- %2520Blood%2520Spatter%2520Analysis. ppt+blood+splatter+analysis&cd=8&hl=tl &ct=clnk&gl=ph Abstract The blood spatters in a crime scene greatly help in identifying the truths in a crime. There are ways to analyze the blood spatters in a scene. The spatters can tell the acts that were done in the scene. It can also tell the area in the scene where the act was done. It can also tell the weapon that was used. Through this, the criminal who did the act may easily be incriminated and the judge and juror may easily give a decision.