2. Warm-Up November 14, 2014 What are the different blood types? What are ways to detect blood at a crime scene?

3. Objective SWBAT analyze blood spatter.

4. Agenda 1.Blood Typing Lab 2.Grave Evidence Documentary 3.Bloodstain Patterns 4.Blood Spatter Lab 5.Forensic Files Friday

5. Forensic Science Blood Typing Lab Activity T. Trimpe 2006 http://sciencespot.net/

6. A small pool of blood and a weapon was found near a garbage dumpster. After examining the area, the CSI on the scene discovered a body in the garbage dumpster and identified him as Earnest “One-Eyed” Earl. Earl had a wound to his chest that will be analyzed by the medical examiner. The CSI tested blood samples from the blood pool and the weapon at the crime scene. It was determined that it was human blood, but he needs to know the blood type to help identify if it was from the victim or the person who murdered him. He has come up with three suspects that either knew the victim or were seen in the area before the body was discovered. He would like to question them further while he waits for DNA test results. Follow your teacher’s directions to complete the lab. Remember to be careful to prevent cross-contamination of the blood samples! Image: http://www.fbi.gov/publications/leb/2005/apr2005/apr2005leb_img_3.jpg The Crime Report

7. We will be determining blood types using Anti-A serum, Anti-B serum, and Anti-RH serum. Use the chart to help you determine the blood type of each sample and its Rh factor (+ or -). Clumping = + (Positive) No Clumping = - (Negative) DIRECTIONS: Step 1: Label the three cups in your kit as Anti-A, Anti-B, and Anti-Rh. Step 2: Place 20 drops of the blood sample in each cup. Step 3: Place 10 drops of the anti-A serum in the A cup. Step 4: Place 10 drops of the anti-B serum in the B cup. Step 5: Place 10 drops of the anti-Rh serum in the Rh cup. Step 6: Use a clean toothpick for each sample and stir for 30 seconds. Blood Typing Test Rh Serum - Clumping = Rh+ blood Type Reaction w/ Anti-A Serum Reaction w/ Anti-B Serum A +- B -+ AB ++ O --

8. Step 7: Record your observations in the correct section on the back of the page and use the reaction chart at the top of this page to determine the blood type. Step 8: Complete the other sections using information from your classmates. Agglutination = Clumping = Positive Reaction Clumping = Positive Result A B Rh What is this person’s blood type? Answer: A+ Rh Serum - Clumping = Rh+ blood Type Reaction w/ Anti-A Serum Reaction w/ Anti-B Serum A +- B -+ AB ++ O --

9. What do your results show? What would you do next in the investigation? Conclusion - = No clumping + = Clumping Results Use + or – to show the test results for each sample and then determine the blood type.

10. Grace Evidence Documentary 7. Where else was high velocity impact spatter found and what does this indicate? 8. What was wrong with the wound track? 9. What was Scher’s motive? 10. How did Scher change his story when he saw the forensic evidence? 11. Why was Dr. Scher’s conviction overturned?

11. Forensic Science Lab Activity T. Trimpe 2006 http://sciencespot.net/ Warning: Some material in this presentation and related videos may be too graphic for some people.

12. 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  Number of blows  Handedness of assailant (right or left-handed)  Position and movements of the victim and assailant during and after the attack  Which wounds were inflicted first  Type of injuries  How long ago the crime was committed  Whether death was immediate or delayed http://www.crimescenetwo.com/img/popup/book2p2.jpg How does a blood droplet form? Click the image for an animation. Source: http://science.howstuffworks.com/bloodstain-pattern-analysis1.htm

13. Light Source Investigators will first examine the crime scene to look for areas that may contain blood. They may use a high-intensity light or UV lights to help them find traces of blood as well as other bodily fluids that are not visible under normal lighting conditions. How is blood evidence detected at a crime scene? Blood Reagent Tests These tests, referred to as presumptive tests, are used to detect blood at crime scenes based upon the properties of hemoglobin in the blood. Further tests at the crime lab can determine if it is human blood or not. Examples: Phenolphthalein is a chemical that is still utilized today and is usually referred to as the Kastle-Meyer test and produces a pink color when it reacts with hemoglobin. HemaStix is a strip that has been coated with tetramethylbenzidine (TMB) and will produce a green or blue- green color with the presence of hemoglobin. Kastle-Meyer Test Video HemaStix

14. Luminol This chemical is used by crime scene investigators to locate traces of blood, even if it has been cleaned or removed. Investigators spray a luminol solution is throughout the area under investigation and look for reactions with the iron present in blood, which causes a blue luminescence. One problem is that other substances also react, such as some metals, paints, cleaning products, and plant materials. Another problem is that the chemical reaction can destroy other evidence in the crime scene. Luminol Reaction LCV or Leuco Crystal Violet, is one type of chemical process that is used for blood enhancement. Using this test helps to make the blood evidence more visible so it can be photographed and analyzed. Fluorescein This chemical is also capable of detecting latent or old blood, similar to luminol. It is ideal for fine stains or smears found throughout a crime scene. After the solution has been sprayed onto the substance or area suspected to contain blood, a UV light and goggles are used to detect any illuminated areas, which appear greenish-white if blood is present. It may also react to many of the same things as luminol (copper and bleach). Fluorescein Reaction in UV Light

15. Bloodstain Pattern Analysis Terms Spatter – Bloodstains created from the application of force to the area where the blood originated. Origin/Source – The place from where the blood spatter came from or originated. Angle of Impact – The angle at which a blood droplet strikes a surface. Parent Drop Spines Satellite Spatters Parent Drop – The droplet from which a satellite spatter originates. Satellite Spatters – Small drops of blood that break of from the parent spatter when the blood droplet hits a surface. Spines – The pointed edges of a stain that radiate out from the spatter; can help determine the direction from which the blood traveled.

16. Passive Bloodstains –Patterns created from the force of gravity –Drop, series of drops, flow patterns, blood pools, etc. Projected Bloodstains –Patterns that occur when a force is applied to the source of the blood –Includes low, medium, or high impact spatters, cast- off, arterial spurting, expiratory blood blown out of the nose, mouth, or wound. Transfer or Contact Bloodstains –These patterns are created when a wet, bloody object comes in contact with a target surface; may be used to identify an object or body part. –A wipe pattern is created from an object moving through a bloodstain, while a swipe pattern is created from an object leaving a bloodstain. Images from http://www.bloodspatter.com/BPATutorial.htm Blood Spatter Movie Types of Bloodstain Patterns

17. Blood Spatters May Reveal: Origin(s) of bloodstain Distance of bloodstain from target Direction from which blood impacted Speed with which blood left its source Position of victim & assailant Movement of victim & assailant Number of blows, shots, etc.

18. Liquid Blood Physical properties –Viscosity – resistance to flow –Surface tension – attraction of molecules inwardly. –Both are about the same as water Behaves as a projectile in motion –Gravity as only force – falls vertically –Gravity with another force – falls vertically and horizontally at the same time

19. Surface Tension Resistant to penetration & separation Acts to reduce surface area A sphere offers the smallest surface area to volume ratio so free falling blood drops are spherical (not “teardrop”) on impact

20. Dripping Blood Blood drop grows until Wt (G) > S.T. Single drop breaks free (teardrop shape) Surface tension pulls in vertically Shape settles into sphere (0.05 ml volume) Does not break up until impact And horizontally Gravity is the only force acting

21. Factors Affecting Drop Size. Standard drop size 50ul (0.05ml). Rapid bleeding gives slightly larger drop Shaking/movement casts off smaller drops Breaks surface tension.

22. Shape & Size of Bloodspot Depends mostly on nature of target surface –Texture (rough or smooth) –Porous or non porous –Angle of impact Size is also related to distance fallen –Given a standard 50 ul drop of blood There is little change in spot diameter beyond a fall distance of 4 ft (1.2m)

23. Drop Size vs. Height Fallen Single drops of blood falling from fingertip onto smooth cardboard from various heights. No change in diameter beyond 7 ft. Adapted from Introduction to Forensic Sciences, W. Eckert, CRC, 1997

24. Height/Surface A blood droplet falling from various heights (ft) onto various surfaces (90 degrees) smoothfloorpapertowelfabric 1.5 3 7 10 1.5 3 7 10

25. Angle of Impact 90  10  70  20  30  60  50  40  Adapted from Introduction to Forensic Sciences, W. Eckert, CRC, 1997 80  Elongated shape; more dense at lower edge

26. Wave Cast-off Angles < 20 degrees to surface David Sadler:. Parent drop wave cast-off Tail of wave cast-off points back to parent drop Tail of elongated stain points in direction of travel

27. Point of Convergence 5 ml of blood squirted from a syringe from a height of 1m

28. Direction and Origin Point of Convergence –Two dimensional –Shows direction Point of Origin –Three dimensional –Shows direction and height

29. Point of Convergence

30. Point of Origin length width Angle of impact = arc sin W/L (Parent Drop) Distance from point of convergence Height above point of convergence Origin 85  60  45  30 

31. Tracing Origin of Bloodspots Point of convergence method –2 dimensional; shows direction Point of origin method –3 dimensional; to include height In practice: –use of string & protractor at scene –use of computer at laboratory

32. Blood Spatter Velocity Low velocity (5 f/s, 1.5 m/s) –Free-falling drops, cast off from weapon Medium velocity (25 - 100 f/s, 7.5 - 30 m/s) –Baseball bat blows High velocity (>100 f/s, >30 m/s) –Gunshot, machinery

33. Low Velocity Blood Spatter Blood source subjected to LV impact –< 5 f/s (1.5 m/s) Spot diameter: mostly 4 - 8 mm –some smaller, some larger Free-falling drops (gravity only) Cast off from fist, weapon, etc. Dripping (blood droplets into themselves) Splashing (stepping, throwing, etc.) Arterial spurting

34. Cast-off from Weapon First blow causes bleeding Subsequent blows contaminate weapon with blood Blood is cast-off at a tangent to arc of upswing or backswing (90 degrees) Pattern & intensity depends on: –type of weapon –amount of blood adhering to weapon –length of arc, swing

35. Downswing of Hammer

36. ............ Dripping Pattern Free-falling drops dripping into wet blood Falling from a stationary object Large irregular central stain Small round & oval satellite stains.........

37. Drip 1: Blood dripping into itself from height of 1 m (8 drops) Notice Irregular Central Stain

38. Drip 2 Blood dripping into itself from height of 1 m (8 drops) Closer View Showing Round and Oval Satellite Stains

39. Splash Pattern Volume > 1 ml –Subjected to LV impact –Thrown –Tipped Large central irregular area surrounded by elongated peripheral spatter pattern

40. Splash 1 5 ml blood squirted from a syringe from a height of 1m

41. Splash 2 5 ml blood squirted from a syringe from a height of 1 m (Closer View of Central Stain)

42. Splash 3 5 ml blood squirted from a syringe from a height of 1 m (Closer View of Peripheral Stains) Direction?

43. Splashing on a vertical surface 6” ruler 10 ml blood thrown 1 m onto a vertical surface

44. Stamp 1 Blood pool (10 drops) before stamping

45. Stamp 2 Blood pool (10 drops) after stamping with shoe

46. Arterial Spurt Pattern Blood exiting body under arterial pressure (120 mm Hg); corresponds to heart beating Large stains with downward flow on vertical surfaces; air bubbles present if lung was punctured Creates a wave-like appearance

47. Arterial Spurt Pattern

48. Medium Velocity Blood Spatter Blood source subjected to MV impact –(25 - 100 f/s, 7.5 - 30 m/s) Spot diameter: mostly 1 - 4 mm Blows with weapon (baseball bat, etc)

49. Cast-off (LV) & Medium Velocity Spatter

50. Cast-off & Medium Velocity Spatter (Close-up)

51. High Velocity Blood Spatter Blood source subjected to HV impact –> 100 f/s, 30 m/s Fine mist: spot size < 0.1 mm Small mass limits spread to 1 m Some larger droplets reach further Gunshot –back-spatter from entry wound –forward spatter from exit wound High speed machinery

52. Gunshot: Back & Forward Spatter Bloodstained foam held just above target surface. Back spatter on entry Forward spatter on exit bullet Bullet passing L to R just above sheet Bullet enters foam bullet exits foam

53. Gunshot Back Spatter Arises from entrance wound Passes back towards weapon & shooter Seen only at close range of fire Seen on: –inside of barrel –exterior of weapon –hand, arm, chest of shooter

54. Back spatter on steadying hand

55. Gunshot Forward Spatter Arises from exit wound Passes forward in same direction as shot More copious than back-spatter Can be seen at any range of fire Seen on nearby surfaces, objects, persons –especially on wall behind victim

56. Forward spatter (5 ms after bullet impacted at 1000 f/s) 2.5 cm blood soaked target bullet

57. 6” ruler Forward spatter on a target (15cm from exit point) due to a HV impact (bullet)

58. Forward Spatter (closer view to show misting)

59. Forward Spatter (closest view) Droplet Size 0.1mm 5 mm

60. Other Patterns Bloodstain patterns that have been altered –Altered by objects, gravity, others Include: –Wipe Patterns –Swipe Patterns –Transfer Patterns –Flow Patterns

61. Wipe and Swipe Patterns Wipe –Object moves through a wet bloodstain –Removes and/or alters bloodstain appearance –Does not require a swipe pattern be present Swipe –Transfer of blood to an unstained surface –Direction may be determined by feathered edge –A wipe pattern must also be present

62. Transfer Patterns Wet, bloodied object contacts a secondary surface Transfer from: –hand, fingers –shoes, weapon –hair Transfer to: –walls, ceilings –clothing, bedding Produces mirror-image of bloodied object

63. Transfer from hair

64. Flow Patterns Blood flows horizontally & vertically Altered by contours, obstacles Often ends in pool

65. Flow Pattern Showing Pooling of Blood

66. Blood Spatter Labs You will be creating sample drop patterns using single drops and multiple drops. We will also investigate the effect of motion and the angle of impact on blood spatter. This can be messy! Be very careful to keep the blood on the paper and not on yourself, the table, or floor. Hold you hand as steady as possible when making the drops. Brace your wrist against the meter stick to help you. Get your materials from your teacher – paper, black marker, meter stick, goggles, and a bottle of blood. If you make a mess, clean it up immediately!

67. Lab 1: Single Droplets 2550 Single Drops Group Members 75100 Single Drops Group Members Label two large pieces of construction paper as shown below. To do the lab, put on your goggles and hold the dropper bottle upside down so that the end of it is 25 cm from the paper. GENTLY squeeze the bottle so that ONE drop of blood is released and lands in the correct location on your paper. It should NOT hit the meterstick. Repeat TWO more times at this height for a total of three drops. Continue making drops of blood on your paper, but put the drop in a different area of the paper and change the height each time. When you are done, analyze your results and answer the questions on your worksheet. Make a mistake? Use a paper towel to wipe it off your paper! Keep your drops in the correct area of the paper.

68. Use your results to answer these questions. What did you notice about the diameter of the parent droplets as you increased the height of the drop? How do the spines compare from the different heights? Lab 1 Questions

69. Lab 2: Multiple Droplets Label a long piece of butcher paper (2 -3 meters in length) as shown below. To do the lab, put on your goggles and hold the dropper bottle upside down so that the end of it is 25 cm from the paper. GENTLY squeeze the bottle so that ONE drop of blood is released and lands in the correct location on your paper. The drop should NOT hit the meterstick. Without moving your hand, release ONE more drop onto the first drop at that height. If you make a mistake, wipe it off with a paper towel and try it again. Continue making drops of blood on your paper so you have three sets for each height. When you are done, analyze your results and answer the questions on your worksheet. Clean up your area and put away your materials before you leave class. Multiple Drops Group Members 255075100 Keep your drops in the correct area of the paper.

70. Use your results to answer these questions. What happened when one drop landed on top of another one? What did you notice about the diameter of the parent droplets as you increased the height of the drop? What do you notice about the diameter of the satellite spatter as you increased the height of the drop? Lab 2 Questions

71. Lab 3: Motion Droplets During this lab, you will see how motion affects the size and shape of the droplets and spines. You will need a long piece of butcher paper (4-5 meters in length) and tape to secure it to the floor. You will also need safety goggles. To do the lab, you will need to hold the dropper bottle upside down so that your hand is out and away from your body (waist level), but is still over the paper. Start off walking at a SLOW WALKING RATE along the paper strip from one end to the other and GENTLY squeeze the bottle as you walk so that blood is released ONE DROP at a time. Be sure that all the drops land on your paper strip. Repeat this procedure using a NORMAL WALKING RATE and a FAST WALKING RATE. Walking Direction When you are done, analyze your results and answer the questions on your worksheet. Clean up your area and put away your materials before you leave class. Miss the paper? Use a paper towel to wipe it off the floor!

72. Use your results to answer these questions. Draw a sketch of the droplets showing the size, shape, and/or distance between them at each speed in the chart below. What did you notice about the shape of the droplets as you increased your walking speed? What did you notice about the spines as you increased your walking speed? What did you notice about the distance between the droplets as you increased your walking speed? Lab 3 Questions

73. Homework Chapter 8 Review, #1-25 due Monday

74. Forensic Files Friday