Firearm injuries_Forensics


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We saw the infamous 26/11 at Mumbai, India. We lost some brave-hearts. Hence, we look into the forensics behind firearm injuries. We shall also discuss the JFK assassination case in brief. I would recommend downloading the presentation and view it in power point 2010 or above to see all the effects flawlessly.

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Firearm injuries_Forensics

  1. 1. FIREARM INJURIES Rifled and Smooth-bore firearm injury Group B
  2. 2. Flow of today’s session
  3. 3. Quick Briefing Proximal Ballistics
  4. 4. Quick Briefing on Forensic Ballistics-Rifled
  5. 5. Quick Briefing on Proximal Ballistics-Shotgun
  6. 6. Firearm Injury General Aspects
  7. 7. Firearm injury-General Aspects Tattooing (peppering/stippling): • Small, descrete, black specks which can’t be wiped off • Caused due to grains of gunpowder driven into skin
  8. 8. Firearm injury-General Aspects Blackening/Smudging: • Carbonaceous deposition on skin which can be easily wiped off. • Caused by deposition of smoke on skin
  9. 9. Firearm injury-General Aspects Lead ring/Metal ring: • Deposition of very small quantity of lead deposition at site of entry of projectile
  10. 10. Firearm injury-General Aspects Grease collar/Dirt collar: • Carried lubricant from the barrel of firearm on the projectile
  11. 11. Firearm injury-General Aspects Entity Distance travelled Injuries/Features exhibited on wound Revolver/ Pistol Rifles Flame 7.5cm 15cm Unburnt gunpowder grains 60cm 75cm, Tattooing 90cm max Partially burnt gunpowder grains Var Var Tattooing Smoke 15cm 20-40cm Blackening/Smudging Projectile Var Var Abrasion collar, contusion collar, grease collar Scorching, singeing(burning)
  12. 12. Firearm injury-General Aspects Position of target Flame RANGE of shooting Contact Gun powder Close Near Distant
  13. 13. Rifled-firearm injury Entry wound and exit wound
  14. 14. Entry wound-Contact shot Point blank shot Cruciate/stellate/star shaped when over a dense area like cranial vault (explosive effects of gases Circular when over thin bone/abdomen with abrasion or contusion collar
  15. 15. Entry wound-Contact shot Burning, blackening and tattooing are slight or absent (driven into the wound) Surrounding hair are singed Imprint of muzzle end may be found stamped on skin
  16. 16. Entry wound-Contact shot Tissues saturated with CO and show cherry red color Diameter of hole + collar = Approx. diameter of the bullet
  17. 17. Entry wound-Close contact Circular hole surrounded by scorching, singeing and smudging Abrasion collar, grease collar and tattooing present
  18. 18. Entry wound-Near shot Circular or oval Singeing of hair and scorching absent Smudging not seen beyond 30cm Grease collar and abrasion collar present
  19. 19. Entry wound-Distant shot Circular with inverted margins Scorching, tattooing and smudging are all absent Grease collar and abrasion collar present
  20. 20. Possibilities are endless…
  21. 21. Entry wound-Summary Shot Shape Contact Cruciate (dense), circular (thin bone,ab domen Close Circular or oval Distant Circular Singeing Smudging Tatooing Abrasion Grease collar collar Not comme -nted Circular Near Scorching Upto 30 cm Upto 90 cm max
  22. 22. Exit wound Vary greatly in size, shape and configuration Usually larger than the corresponding wound of entry Scorching, blackening, and tattooing absent Abrasion collar and grease collar also absent Edges invariably everted Outward beveling in case of skull
  23. 23. Exit wound Demonstrating Exit wound by experimenting air rifle at MGIMS Dept.of Forensic Medicine and Toxicology- (Credit: Dr.Vishal Surwade)
  24. 24. Exit wound-Summary Shape Variable, usually larger than correspo nding entry wound Scorching Singeing Smudging Tatooing Abrasion collar Grease collar
  25. 25. Difference between Entry wound and Exit wound
  26. 26. Entry and Exit wound gross appearance
  27. 27. Case of close entry and exit wound
  28. 28. Differentiating entry from exit Characteristics Entry wound Exit wound Size Smaller than diameter of bullet Larger Edges Inverted Everted Abrasion and grease collar Present Absent Burning, blackening, tattooing May be present Absent Bleeding Less More Fat extrusion Absent May be present Cherry red May be present Absent Lead ring May be present Absent
  29. 29. Smooth-bore firearm injury Entry wound and Exit wound
  30. 30. It’s different from bullets-It’s pellets
  31. 31. Entry wound-Contact shot Large irregular hole (Explosive blast effect) Scorching, tattooing and blackening present Imprint abrasion may be present Shot enters as a solid mass
  32. 32. Entry wound-Contact shot Cherry red colored injured tissue In cranium, large and irregular wound with fissured fractures radiating outwards from the margin
  33. 33. Entry wound-Close shot Circular defect with irregular inverted borders Edges show scorching and blackening Fairly wide zone of tattooing
  34. 34. Entry wound-Close shot Cherry red appearance of tissues Pellets enter enmasse Wads and cartridge parts may contribute to the wound
  35. 35. Entry wound-Near shot Circular or oval Smudging not beyond 30cm Wads may produce mild abrasions (upto 30cm only) Wide area of tattooing
  36. 36. Entry wound-Distant shot Beyond 2m, no burning or blackening Tattooing is rare Wads may contribute upto 5m
  37. 37. Entry wound-Distant shot Significant dispersion of pellets beyond 2m and increases progressively • Old thumb rule: Diameter of spread in inches is roughly equal to range in yards x 1.5 Beyond 6m central defect diminishes to nothing and lethality is very less
  38. 38. Medicolegal aspects Firearm injuries
  39. 39. MLA Firearm injuries 1 Nature of firearm 2 Range of fire 3 Direction of fire 4 Place from where firing took place 5 6 Cause of death Manner of death-Accidental, suicidal or homicidal
  40. 40. Putting Forensic science to use Feature Accidental Suicidal Homicidal Site of entry wound Any part Head/Chest Any part Range Close Contact/Close Any range Direction Any direction Upward/backward Usually upward No. of wounds One Usually one One or multiple Firearm residue on hand Present Present Absent Weapon at scene Present Present Usually absent Location Anywhere Usually home Anywhere Sex Usually males Usually males Either sex Motive Absent Depression, mental illness Robbery, revenge
  41. 41. Ballistic Trivia Just fun to know…
  42. 42. Types of lead shot Dust shotConsists of extremely fine particles Bird shotConsists of lead pellets of average diameter 3.5mm, used for small game hunting Buck shotConsists of large pellets of average diameter 6-8mm, used for big game hunting
  43. 43. Unusual Ballistic effects O Billiard ball effect
  44. 44. Unusual Ballistic effects O Tandem bullet:
  45. 45. Unusual Ballistic effects O Shored exit wound
  46. 46. Unusual Ballistic effects O Yawing bullet
  47. 47. Unusual Ballistic effects O Tumbling bullet:
  48. 48. Unusual Ballistic effects O Souvenir bullet: A bullet remaining from a long time in the body without invoking any certain discomfort or visible damage.
  49. 49. Unusual Ballistic effects O Kennedy phenomenon: Alteration of firearm wound due to surgical intervention
  50. 50. He fired a GUN, I’m sure O Dermal Nitrate test: O Cloth dipped in molten paraffin is wrapped on the hands of the accused O Then, cloth is removed and is treated with diphenylamine reagent on its internal surface O Appearance of blue color indicates positive test O More specific and sensitive tests: Harrison and Gilroy’s test, Neutron activation analysis and atomic absorption spectroscopy
  51. 51. One of the most sensational cases of assassination by firearm That is mired in controversy EVEN TODAY
  52. 52. Who really shot John F. Kennedy?
  53. 53. Place of assassination
  54. 54. Lee Harvey Oswald arrested
  55. 55. Jack Ruby killed Oswald
  56. 56. President Lyndon Johnson appointed a commission
  57. 57. Headed by SCCJ Earl Warren
  58. 58. 552 witnesses 1000s of pages of evidence Final report running into 26 volumes in 1964 Stated that Lee Harvey Oswald acted alone in the killing
  59. 59. Controversy Oswald fired 3 bullets But the trajectory of second shot is doubtful Suggestive of four bullets That means a 2nd gunman
  60. 60. Conspiracy doubted Lyndon Johnson bitter over his defeat by Kennedy for 1960 democratic nomination and fearing he would be dumped as Vice President JFK movie 1991 by Oliver Stone suggested New Orleans businessman Clay Shaw involved Clay Shaw was Actually arrested but aquitted for lack of evidence
  61. 61. Conclusion Still wide belief Oswald was the sole mastermind But still people keep questioning WHO REALLY SHOT JOHN.F.KENNEDY?
  62. 62. All the text is from Textbook of FMT- Dr.V.V Pillay, images taken from K.S.N. Reddy,, relentless, google images and edited in paint, photoshop, powerpoint and movie maker, Adobe capture