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Investigative Photography and Crime Scene Sketches

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  1. Investigative PhotographyandCrime Scene Sketches Thanks to Steve Gilbert, MFSCriminal Investigations ProgramSUNY at Canton

  2. Crime Scene Photography • One of the FIRST investigative tasks!!! • Types of cameras used: 35mm SLR Video Digital Polaroid

  3. Crime Scene Photography • Advantages of photographs Can be taken immediately Can accurately depict crime scene Creates interest Supports testimony • Disadvantages of photographs Do not show actual distances Can be distorted Digital images can be altered

  4. Advantages of Video Taping • Increases Intoxication convictions - DUI • Enhances officer integrity • Provides officer safety • Documents traffic violations • Reduces court time for officers • Lowers liability for misconduct claims • Documents probable cause and evidence

  5. Disadvantages of Video Taping • Records unwanted sound • Documents errors made by officers and technicians • Officers not always trained • Discrepancies with Time/Date stamp

  6. Types of Photographs Establishing photographs depict an overall view of the scene, buildings, approach and escape routes, witnesses, etc. Medium-rangephotographs depict the relationship between objects, concentrates more on the immediate scene. Close-up photographs depict individual items of evidence.

  7. This establishing photograph depicts the overall crime scene.

  8. This medium-range photograph depicts the actual scene and relationship of evidence.

  9. This close-up photograph depicts a single item of evidence.

  10. Flash photography is often needed during the day. As seen in the photograph, the camera’s eye is fooled by the bright brickwork, while the evidence is in darkness.

  11. Same photograph, but with a flash. Now the evidence can be seen.

  12. Photographs should contain rulers or objects to help establish the size of the evidence. In this instance, the known length of the bill can be used as a scale to determine the length of the knife.

  13. Macroscopic photographs depict details of objects, and are taken at extreme close range.

  14. The General Uses of Photography • Crime scene documentation • Surveillance of people and locations • Mug shots • Line-ups • Laboratory examination of evidence

  15. Crime Scene Sketches Sketches are important supplements to photographs and crime scene reports. Sketches…. • Accurately portray physical facts • Relate to the sequence of events • Establish locations and relationships • Provide an overall picture of the scene • Are a permanent record of the scene

  16. Crime Scene Sketches The rough sketch is drawn at the crime scene. It is not a finish product, although it does contain measurements and other data. The finished sketch is often drawn by a draftsman to show proper relationships and scales. The finished sketch is more presentable for court presentations.

  17. Steps in Sketching the Crime Scene 1. Observe the scene and plan the sketch 2. Measure distances 3. Outline the area (area dimensions) 4. Locate and draw objects and evidence within the sketch 5. Record all details 6. Depict legend, title, scale and direction of North

  18. Triangulation Method of Locating Evidence A 8’ 10’ Item A is 10’ from the SE corner of the room, and 8’ from the SW corner of the room. These measurements will ALWAYS intersect at item A’s location.

  19. Triangulation Method of Locating Evidence A desk Evidence must be triangulated to two fixed points. Not using the corners of the room, how would object A be triangulated?

  20. Triangulation Method of Locating Evidence A desk First, the desk is not fixed, as it is not touching the wall and its location has not been determined. To fix the desk, do this:

  21. Triangulation Method of Locating Evidence 3’ A desk 1” Now that the desk has been fixed, object A can be fixed from two fixed points from the desk, as such:

  22. Triangulation Method of Locating Evidence 3’ A 5’ desk 6’ 1” Now that the desk has been fixed, object A can be fixed from two fixed points from the desk, as such:

  23. Triangulation Method of Locating Evidence A desk In this scenario, the desk is flush against the wall. How would object A be triangulated?

  24. Triangulation Method of Locating Evidence 3’ A 5’ desk 6’ The flush side of the desk is already fixed. One measurement is required to place the desk along the wall. Object A is then triangulated as usual.

  25. Triangulation Method of Locating Evidence desk A This desk is flush in the corner against both walls. How would object A be triangulated?

  26. Triangulation Method of Locating Evidence desk 6’ A 5’ Since two sides of the desk are already fixed, object A is triangulated as usual.

  27. Triangulation Method of Locating Evidence desk 6’ A 5’ 2’ 2’ B Once evidence is triangulated, it can become a fixed point to triangulate other items of evidence. In this case, object B.

  28. Rectangular-Coordinate Method A 15’ B 6’ 10’ 6’

  29. Azimuth Method of Triangulation Tree 340° 160° 40° Shed 220° Reverse azimuth:340°-180°=160° N Reverse azimuth:40°+180°=220° W E Body S Compass

  30. Administrative Data LEGENDA. VictimB. RevolverC. Shell CasingD. Blood Stain TITLECase: 1234-2001Location: Payson Hall, Room 111Victim: State of New YorkOccurred: Oct 31, 2001, 2300Drawn by: Detective GilbertVerified by: Detective Marlowe Not to Scale North Or¼” = 1 foot

  31. Rules for Drawing Sketches • Never measure through space • “Rotating” items require measurements at opposite ends • Oddly shaped items, such as puddles of liquids, are triangulated from center of mass • Do not cross measurement lines • Always have the sketch verified

  32. 10” 13” Since the blood droplets are of no particular defined shape, they are triangulated to the “center of mass”

  33. Projection Sketch