Essay on Blood and Fingerprints

One of the most important purposes of physical evidence is to establish the identity of a suspect or victim. Some of the most valuable clues at a crime scene are fingerprints. "Processing a crime scene" is a long, tedious process that involves focused documentation of the conditions at the scene and the collection of any physical evidence that could possibly shed light on what happened and point to who did it.

In quadrants 1 and 2 how the amount and constituents of the fingerprint residue on the substrate affects the fingerprint image, is determined. In quadrant 1, excess sebum and moisture is first removed from the finger tips with the help of a clean cloth. In quadrant 2, fingertip is first wiped around the nose or forehead to create excess sebum. Quadrant 3 and 4 were used to compare the details between untreated and dusted fingerprint residues.

The understanding of blood spatter patterns is not a widely recognized forensic practice. Bloodstain pattern interpretation (BPI) is commonly used in murder investigations, but could be utilized in everything from simple assault to mass murders if the number of trained professionals increased. BPI can reveal critical information into reinventing a given crime scene. Everything from the number of blows, stabs or shots a victim was given, the movement that was undergone by the victim and assailant after bloodshed began, position of objects at the crime scene and the type of weapon, if any, that was used can be uncovered.

Center, National Forensic Science Technology. (2015, January 27). Principles of Fingerprint Analysis. Retrieved from Forensic Science Simplified: http://www.forensicsciencesimplified.org/prints/principles.html

The general charactertics of blood are color, composition, and pH. The composition of blood is determined by collecting blood from a person then it’s placed in a centrifuge which shows plasma is 55% of whole blood and 45 % is erythrocytes. Another name for red blood cells is erythrocytes which are small sacs of blood that carry oxygen and

To name the two major components of blood and state their average percentages in whole blood.

There are different types of patterns that blood splatter makes. It can be a drop, a messy splatter, to just a little pool of blood it all just depends on what caused it to happen. Forensics and law enforcement officers can determine what kind of object was used in a murder case based on the blood splatter pattern.

Then, there would be tests for hemoglobin and hematocrit. When these individuals had their blood drawn, it would be searched for diseases like HIV, hepatitis B and C, and malaria. Soldiers never found out whose clean blood they were getting, whether it was American, foreign, or even their enemies. When nurses were ready to give the fresh blood to their patients, they would rehearse a plan to minimize any delay or contamination (Strube). When everything had gone well, they would then place the patient on a 450-ml bag of fresh whole blood that matches their blood type.

After Galton’s discovery, the use of fingerprinting by law enforcement was inevitable. In 1892, an Argentine police official, Juan Vucetich, became the first person to identify a criminal through fingerprints (The History of Fingerprints). The last major step necessary for the widespread use of fingerprint identification was to create a classification system that simplified the process of matching fingerprints. That came in 1901, when Edward Henry devised a system that separated fingerprints into four different categories - loops, whorls, arches, and composites (Skopitz). Shortly after its development, most European nations implemented this system of

Forensic science is a key aspect of Criminal Justice that helps rid the streets of lunatics and murderers. One of the most important fields of forensic science is blood spatter analysis. Under the Crime Scene Investigation, analysts gather the information that could eventually lead to a victim’s killer. Basic and complex information can be found when analyzing blood. We can learn what kind of weapon was used, the time of death of a victim and other important facts that can help a case. The pattern that the blood gives off give forensic scientists the tools that they need to help solve cases.

Spatter Patterns Experiment When arriving at a crime scene a lot can be learnt by the blood and the way in which it has spattered. If there is no body, forensic scientists can use the blood spatters to determine where from and at what angle the blood came as well as the size of the weapon and the point of origin of the blood spatter. Investigative Question How does blood spatter determine the angle and point of origin of the blood?

In 1667, Jean-Baptiste Denis from France reported transfusing blood from lambs into human, which was later declared illegal. An American physician, from Philadelphia, performed the first human to human blood transfusion but did not report it when he did so in 1795. James Blundell, a british obstetrician, successfully performed a transfusion for a patient with postpartum hemorrhage in 1818 and later performed 10 more and half were successful. In 1840, Samuel Armstrong Lane helped with the first transfusion to treat hemophilia and in 1867, and English surgeon named Joseph Lister used antiseptics to reduce the risk of infections during transfusions. In 1900 an Austrian physician discovered the first 3 human blood groups, A, B, and C that was later renamed O. Hepatitis B was found in blood n 1971 so testing on donor blood began and in 1985, the first blood screening test for HIV was licensed and used in blood banks around the world to protect the supply of blood.

There are different types of patterns for fingerprints, there are Arches, Loops, and Whorls. An Arch is found in five percent of fingerprints encountered. There are two types of Arches a Plain Arch, and a Tented Arch. Therefore they are the rarest. Loops are found in sixty to seventy percent of fingerprints encountered. Therefore they are the most common. Whorls are found in twenty five to thirty five percent of fingerprints encountered. There are four types of fingerprints, the Plain Whorl, Central Pocket Whorl, Double Loop Whorl, and the Accidental Whorl.

Forensic scientist use the 'ABO blood grouping System', which is a system that measures antigens within the body to determine blood type and are normally

Fingerprint patterns are classified into three main categories: loops, whorls, and arches. Loops make up sixty percent of the prints that are left behind, and their patterns trace back onto themselves, pointing either towards the thumb or the pinky. Whorls make up thirty-five percent of prints left behind, and they are circular in nature. These have many classifications and patterns: they can be concentric circles, or plain whorls; they can be loops with whorls at