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Chapter 10 Blood “Out damned spot! Out, I say Here’s the smell of the blood still, All the perfumed of Arabia will not Sweeten this little hand. Oh, Oh,

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Presentation on theme: "Chapter 10 Blood “Out damned spot! Out, I say Here’s the smell of the blood still, All the perfumed of Arabia will not Sweeten this little hand. Oh, Oh,"— Presentation transcript:

1 Chapter 10 Blood “Out damned spot! Out, I say Here’s the smell of the blood still, All the perfumed of Arabia will not Sweeten this little hand. Oh, Oh, Oh!” —William Shakespeare’s Lady Macbeth, in Macbeth

2 Chapter 10Kendall/Hunt Publishing Company1 Blood

3 Chapter 10Kendall/Hunt Publishing Company2 Blood  That an antibody and an antigen of different types will agglutinate, or clump, when mixed together.  That the significance of the evidence depends on a characteristic’s relative occurrence in the population. Students will learn:

4 Chapter 10Kendall/Hunt Publishing Company3 Blood Students will be able to:  Determine whether a stain is blood.

5 Chapter 10Kendall/Hunt Publishing Company4 Blood  Determine the blood type of a simulated bloodstain using the ABO/Rh system.  Explore bloodstain patterns as a function of velocity, direction, and height of fall.

6 Chapter 10Kendall/Hunt Publishing Company5 Blood  Use technology and mathematics to improve investigations and communications.

7 Chapter 10Kendall/Hunt Publishing Company6 Serology Serology is the examination and analysis of body fluids. A forensic serologist may analyze a variety of body fluids including saliva, semen, urine, and blood. From 1950 to the late 1980’s, forensic serology was a most important part of lab procedures.

8 Chapter 10Kendall/Hunt Publishing Company7 Serology With the development of DNA techniques, more time, money, and significance was placed in developing DNA labs. However, with limited funds and the time required for DNA testing, most labs still use many of the basic serology testing procedures.

9 Chapter 10Kendall/Hunt Publishing Company8 Blood Characteristics

10 Chapter 10Kendall/Hunt Publishing Company9 Blood Characteristics  Erythrocytes  Leukocytes  Thrombocytes  Serum

11 Chapter 10Kendall/Hunt Publishing Company10 Blood Characteristics  Plasma is the fluid portion of the blood (55%)  Cells (45%)  Erythrocytes are red blood cells. They are responsible for oxygen distribution.

12 Chapter 10Kendall/Hunt Publishing Company11 Blood Characteristics  Leukocytes are the white blood cells; they are responsible for “cleaning” the system of foreign invaders.  Thrombocytes or platelets are responsible for blood clotting  Serum is the liquid that separates from the blood when a clot is formed.

13 Chapter 10Kendall/Hunt Publishing Company12 Historical Perspective of Blood Typing Around 1900, Karl Landsteiner discovered that there are four different types of human blood based on the presence or absence of specific antigens found on the surface of the red blood cells.

14 Chapter 10Kendall/Hunt Publishing Company13 Historical Perspective of Blood Typing In 1940, Landsteiner and Weiner reported the discovery of the Rh factor by studying the blood of the Rhesus monkey. 85% of Caucasians, 94% of Black Americans and 99% of all Asians are Rh positive.

15 Chapter 10Kendall/Hunt Publishing Company14 Blood Terminology  ABO blood groups—based on having an A, B, both or no antigens on red blood cells  Rh factor—may be present on red blood cells; positive if present and negative if not

16 Chapter 10Kendall/Hunt Publishing Company15 Blood Terminology  Antigen—a substance that can stimulate the body to make antibodies. Certain antigens (proteins) found in the plasma of the red blood cell’s membrane account for blood type.

17 Chapter 10Kendall/Hunt Publishing Company16

18 Chapter 10Kendall/Hunt Publishing Company17 Blood Terminology  Antibody—a substance that reacts with an antigen  Agglutination—clumping of red blood cells; will result if blood types with different antigens are mixed

19 Chapter 10Kendall/Hunt Publishing Company18 Unagglutinated blood smear Agglutinated blood

20 Chapter 10Kendall/Hunt Publishing Company19 Antibodies seeking specific antigens Antibodies agglutinating red cells (not actual shape or size of antigens and antibodies)

21 Chapter 10Kendall/Hunt Publishing Company20 Unknown Stain at a Scene Questions to be answered:  Is it blood?  Is it human blood?

22 Chapter 10Kendall/Hunt Publishing Company21 Unknown Stain at a Scene  Whose is it?  Determine blood type, alcohol content, drugs present  Determine the method(s) in which blood may have been deposited WHY?

23 Chapter 10Kendall/Hunt Publishing Company22 Presumptive Tests for Blood Determination  Kastle-Meyer color test—a mixture of phenolphthalein and hydrogen peroxide; the hemoglobin will cause the formation of a deep pink color if blood is present What does presumptive mean?

24 Chapter 10Kendall/Hunt Publishing Company23 Presumptive Tests for Blood Determination  Hematest® tablet—reacts with the heme group in blood causing a blue-green color  Luminol test—reaction with blood to produce light

25 Chapter 10Kendall/Hunt Publishing Company24  Leucomalachite test – a mixture of leucomalachite green, acetic acid and distilled water is placed on sample; then a drop of sodium perborate added will turn blood a green- ish color Presumptive Tests for Blood Determination

26 Chapter 10Kendall/Hunt Publishing Company25 Human vs Animal Blood  Microscopic observation  Precipitin test Precipitin: an antibody that reacts with a specific antigen to produce a precipitate

27 Chapter 10Kendall/Hunt Publishing Company26 Human vs Animal Blood  Precipitin test—blood is injected into a rabbit;  antibodies are formed;  the rabbit’s blood is extracted as an antiserum;  the antiserum is placed on sample blood.

28 Chapter 10Kendall/Hunt Publishing Company27 Human vs Animal Blood  Precipitin test  The sample will react with human proteins, if human blood is present.  This test is very sensitive and requires only a small amount of blood.

29 Chapter 10Kendall/Hunt Publishing Company28 Animal Blood Larger nucleic red blood cells Frog Blood

30 Chapter 10Kendall/Hunt Publishing Company29 Human Blood  Red blood cells are most numerous; 5 to 6 million per mm 3  White blood cells are larger and less numerous; 5 to 10,000 per mm 3

31 Chapter 10Kendall/Hunt Publishing Company30 Human Blood  Platelets are tiny, cellular fragments; 350 to 500,00 per mm 3

32 Chapter 10Kendall/Hunt Publishing Company31 Blood Typing  Blood type A has antigen A on the surface of the cell and will agglutinate with blood type B.  Blood type B has antigen B on the surface of the cell and will agglutinate with blood type A.

33 Chapter 10Kendall/Hunt Publishing Company32 Blood Typing  Blood type AB has antigens A and B on the surface of the cells and will agglutinate with either anti A or anti B antibody.  Blood type O has neither antigen A or B and will not agglutinate.

34 Chapter 10Kendall/Hunt Publishing Company33 Blood Groups Type Antigen Antibody Can Give Blood To Can Get Blood From A B AB O A B A and B Neither A nor B B A Neither A nor B A and B A, ABO, A B, ABO, B AB A, B, O, AB O

35 Chapter 10Kendall/Hunt Publishing Company34  Antiserum- human or animal serum containing antibodies that are specific for one or more antigens.

36 Chapter 10Kendall/Hunt Publishing Company35 Blood Reactions to Antiserum REACTION BLOOD TYPE Anti-A SerumAnti-B Serum Agglutination No agglutination Agglutination No agglutination Agglutination No agglutination Type A Type B Type AB Type O

37 Chapter 10Kendall/Hunt Publishing Company36 Population Distribution of Blood Types in the U.S. TypePercent O A B AB 45 40 11 4

38 Chapter 10Kendall/Hunt Publishing Company37

39 Chapter 10Kendall/Hunt Publishing Company38 Typing of Dried Blood Stains Absorption – elution technique  Antiserum is placed on the blood stain. Antibodies combine with the specific antigens.  Unreacted serum is washed off the bloodstain.

40 Chapter 10Kendall/Hunt Publishing Company39 Typing of Dried Blood Stains  Stained material is heated to 56 degrees C, breaking the antibody- antigen bond. This process is known as elution.  Known red blood cells are added. Agglutination will occur if antigens present on the added RBC’s were also originally on the stained material.

41 Chapter 10Kendall/Hunt Publishing Company40 Blood Pattern Reconstruction Scene Pattern Reconstruction 1. Stain condition 2. Pattern 3. Distribution 4. Location 5. Directionality —From “Cracking Cases” by Dr. Henry C. Lee

42 Chapter 10Kendall/Hunt Publishing Company41 Blood Pattern Reconstruction Lab Results Reconstruction 1. Genetic marker typing 2. Age Determination 3. Source Determination 4. Race Determination 5. Sex Determination —From “Cracking Cases” by Dr. Henry C. Lee

43 Chapter 10Kendall/Hunt Publishing Company42 Blood Spatter Evidence A field of forensic investigation which deals with the physical properties of blood and the patterns produced under different conditions as a result of various forces being applied to the blood. Blood, as a fluid, follows the laws of physics.

44 Chapter 10Kendall/Hunt Publishing Company43 People of Historical Significance Paul Kirk (1902-1970) was a professor of criminalistics and biochemistry at Berkeley in California. He actively assisted law enforcement organizations from 1935 to 1967. His book, Crime Investigations, contained a chapter in which he discussed the application of blood stain pattern analysis to criminal investigations. Dr. Kirk analyzed the blood stain pattern photos from the Sam Sheppard case and was instrumental in Sheppard’s release at his second trial. Find out more about the case at Courttv’s crime library.

45 Chapter 10Kendall/Hunt Publishing Company44 Blood Droplet Characteristics  A blood droplet will remain spherical in space until it collides with a surface  Once a blood droplet impacts a surface, a bloodstain is formed.

46 Chapter 10Kendall/Hunt Publishing Company45 Blood Droplet Characteristics  A droplet falling from the same height, hitting the same surface at the same angle, will produce a stain with the same basic shape.  How will the shape change as the height is increased or decreased?

47 Chapter 10Kendall/Hunt Publishing Company46 Blood Droplet Volume  A droplet contains approximately 0.05 cc of fluid  Is not the same for all blood droplets, but is generally from 0.03 cc to 0.15 cc

48 Chapter 10Kendall/Hunt Publishing Company47 Blood Droplet Volume  Is directly dependent upon the surface or orifice from which it originates  The impact area is called the target.

49 Chapter 10Kendall/Hunt Publishing Company48 Conditions Affecting Shape of Blood Droplet  Size of the droplet  Angle of impact  Velocity at which the blood droplet left its origin

50 Chapter 10Kendall/Hunt Publishing Company49 Conditions Affecting Shape of Blood Droplet  Height  Texture of the target surface  On clean glass or plastic —droplet will have smooth outside edges  On a rough surface —will produce scalloping on the edges

51 Chapter 10Kendall/Hunt Publishing Company50 Questions Answered by Blood Spatter Interpretation  The distance between the target surface and the origin of blood  The point(s) of origin of the blood

52 Chapter 10Kendall/Hunt Publishing Company51 Questions Answered by Blood Spatter Interpretation  Movement and direction of a person or an object  The number of blows, shots, etc. causing the bloodshed and/or the dispersal of blood.

53 Chapter 10Kendall/Hunt Publishing Company52 Questions Answered by Blood Spatter Interpretation  Type and direction of impact that produced the bloodshed  The position of the victim and/or object during bloodshed  Movement of the victim and/or object after bloodshed

54 Chapter 10Kendall/Hunt Publishing Company53 Bloodstain Terminology  Angle of impact—angle at which blood strikes a target surface.

55 Chapter 10Kendall/Hunt Publishing Company54 Bloodstain Terminology  Bloodstain transfer—when a bloody object comes into contact with a surface and leaves a patterned blood image on the surface

56 Chapter 10Kendall/Hunt Publishing Company55 Bloodstain Terminology  Backspatter—blood that is directed back toward the source of energy  Cast-off—blood that is thrown from an object in motion

57 Chapter 10Kendall/Hunt Publishing Company56 Bloodstain Terminology  Contact stain—bloodstains caused by contact between a wet blood-bearing surface and a second surface which may or may not have blood on it

58 Chapter 10Kendall/Hunt Publishing Company57 Bloodstain Terminology  Transfer—an image is recognizable and may be identifiable with a particular object  Swipe—wet blood is transferred to a surface which did not have blood on it

59 Chapter 10Kendall/Hunt Publishing Company58 Bloodstain Terminology  Wipe—a non-blood bearing object moves through a wet bloodstain, altering the appearance of the original stain

60 Chapter 10Kendall/Hunt Publishing Company59 Bloodstain Terminology  Directionality—relates to the direction a drop of blood traveled in space from its point of origin

61 Chapter 10Kendall/Hunt Publishing Company60 Bloodstain Terminology  Terminal velocity—the greatest speed to which a free falling drop of blood can accelerate in air. It is dependent upon the acceleration of gravity and the friction of the air against the blood— approximately 25.1 feet/second.

62 Chapter 1061 Bloodstain Terminology High velocity greater than 25 feet per second usually 100 feet per second gives a fine mist appearance

63 Chapter 1062 Bloodstain Terminology Medium velocity 5 to 25 feet per second Low velocity 5 feet per second or less

64 Chapter 10Kendall/Hunt Publishing Company63 Bloodstain Patterns The shape of a blood drop:  Round—if it falls straight down at a 90 degree angle.

65 Chapter 10Kendall/Hunt Publishing Company64 Bloodstain Patterns  Elliptical—blood droplets elongate as the angle decreases from 90 to 0 degrees; the angle can be determined by the following formula:

66 Chapter 1065 Categories of Blood Stains

67 Chapter 10Kendall/Hunt Publishing Company66 Passive

68 Chapter 10Kendall/Hunt Publishing Company67 Transfer

69 Chapter 10Kendall/Hunt Publishing Company68 Projected

70 Chapter 10Kendall/Hunt Publishing Company69

71 Chapter 10Kendall/Hunt Publishing Company70 Arterial Spurt

72 Chapter 10Kendall/Hunt Publishing Company71 LOWMEDIUM

73 Chapter 10Kendall/Hunt Publishing Company72 HIGH VELOCITY

74 Chapter 10Kendall/Hunt Publishing Company73 Impact  The more acute the angle of impact, the more elongated the stain.

75 Chapter 10Kendall/Hunt Publishing Company74 Impact  90 degree angles are perfectly round drops with 80 degree angles taking on a more elliptical shape.

76 Chapter 10Kendall/Hunt Publishing Company75 Impact  At about 30 degrees the stain will begin to produce a tail.  The more acute the angle, the easier it is to determine the direction of travel.

77 Chapter 10Kendall/Hunt Publishing Company76 Impact

78 Chapter 1077

79 Chapter 1078

80 Chapter 10Kendall/Hunt Publishing Company79 Bloodstain Patterns  The harder and less porous the surface, the less the blood drop will break apart.

81 Chapter 10Kendall/Hunt Publishing Company80 Bloodstain Patterns  The softer and more porous the surface, the more a blood drop will break apart.  The pointed end of the blood stain faces the direction of travel.

82 Chapter 10Kendall/Hunt Publishing Company81

83 Chapter 10Kendall/Hunt Publishing Company82 Area of Intersection and Convergence The location of the blood source can be determined by drawing lines from the various blood droplets to the point where they intersect.

84 Chapter 10Kendall/Hunt Publishing Company83 Area of Intersection and Convergence The Point of Convergence: The intersection of two bloodstain paths, where the stains come from opposite sides of the impact pattern.

85 Chapter 10Kendall/Hunt Publishing Company84 Area of Intersection and Convergence

86 Chapter 1085 Area of Intersection and Convergence The area of convergence is the point of origin; the spot where the “blow” occurred. It may be established at the scene with measurement of angles by use of strings.

87 Chapter 10Kendall/Hunt Publishing Company86 Area of Intersection and Convergence

88 Chapter 10Kendall/Hunt Publishing Company87 Blood Evidence  Class evidence for blood would include blood type. If you can determine the DNA you would have individual evidence.

89 Chapter 10Kendall/Hunt Publishing Company88 Blood Evidence  Blood stain patterns are considered circumstantial evidence in a court room. Experts could argue many points including direction of travel, height of the perpetrator, position of the victim, left/right hand, whether the body was moved, etc.

90 Chapter 10Kendall/Hunt Publishing Company89 Other Aspects of Serology – Sperm  Among the smallest and most highly specialized cells in the human body  Has a head and a tail 400X

91 Chapter 10Kendall/Hunt Publishing Company90 Other Aspects of Serology – Sperm  Contains 23 chromosomes with the genetic material found in the head  Males release 2.5 to 6 milliliters of seminal fluid per ejaculation with approximately 100 million sperm per milliliter

92 Chapter 10Kendall/Hunt Publishing Company91 Semen Determination of Seminal Fluid  Acid phosphatase color test  The presence of acid phosphatase, the enzyme secreted by the prostate gland into the seminal fluid, will turn purple when sodium alpha naphthylphosphate and Fast Blue B solution are placed on it.

93 Chapter 10Kendall/Hunt Publishing Company92 Semen  It will also fluoresce under UV light when it comes in contact with 4- methyl umbelliferyl phosphate.

94 Chapter 10Kendall/Hunt Publishing Company93 Semen  Prostate Specific Antigen (PSA) or p30 – unique to seminal plasma  P30 is isolated and injected into a rabbit where antibodies are produced (anti-p30).

95 Chapter 1094 Semen  The stain extract is place in one well of an electrophoresis plate and the anti-p30 in the opposite well. The electric is applied and the antigens and antibodies move toward each other. The formation of a precipitation line between the wells shows the presence of p30 in the sample stain. It, therefore, must be seminal fluid.

96 Chapter 10Kendall/Hunt Publishing Company95 Secretors 80% of the population are secretors. Their blood-type antigens are found in high concentration in their body fluids such as saliva, semen, vaginal secretions and gastric juice.

97 Chapter 10Kendall/Hunt Publishing Company96 People in the News Herbert L. MacDonell is considered by many as the father of modern bloodstain pattern analysis. He is the director of the Lab of Forensic Science and founder of the Bloodstain Evidence Institute (1973) in Corning, NY. His work, Bloodstain Pattern Interpretation, helped to jump start this discipline. He has consulted on criminal cases in all 50 states, in addition to testifying in the O.J. Simpson trial and in the assassination cases of Sen. Robert F. Kennedy and Dr. Martin Luther King Jr.

98 Chapter 10Kendall/Hunt Publishing Company97 More about Serology For additional information about blood evidence, and famous crimes that involves serology, check out Court TV’s Crime Library at: www.crimelibrary.com/criminal_mind/forensics/serology/1.html


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