Crime Scene Investigation

1. Crime Scene Investigation

2. “There is not only the effect of the criminal on the scene to be considered, but also the manner in which the scene may have imparted traces to the criminal”(Charles E. O’Hara, Fundamentals of Criminal Investigation).

3. “There is not only the effect of the criminal on the scene to be considered, but also the manner in which the scene may have imparted traces to the criminal”(Charles E. O’Hara, Fundamentals of Criminal Investigation). This quote is a restatement of Locard’s Exchange Principle

4. What is a crime scene? • As small as a computer or as large as a plane crash • A crime scene is the largest area that may contain evidence for later investigation

5. What is physical evidence? • Includes any and all objects that can establish that a crime has been committed or that can provide a link between a crime and its victim or a crime and its perpetrator

6. Why Forensic Science? • Forensic science is an important element of the total investigative process • It begins at the crime scene

7. What does crime scene investigation consist of? • Crime scene investigation consists of certain preliminaries

8. What does crime scene investigation consist of? • Crime scene investigation consists of certain preliminaries • Followed by documentation

9. What does crime scene investigation consist of? • Crime scene investigation consists of certain preliminaries • Followed by documentation • Then the collection and

10. What does crime scene investigation consist of? • Crime scene investigation consists of certain preliminaries • Followed by documentation • Then the collection and • Preservation of evidence

11. After these things occur, the crime scene can be reconstructed • REMEMBER-- at all times certain legal considerations must be followed.

12. Preliminary Actions • It is the responsibility of the first officer on the scene to take steps to preserve and protect the area.

13. Preliminary Actions • The priorities are:

14. Preliminary Actions • The priorities are: • save and preserve life

15. Preliminary Actions • The priorities are: • save and preserve life • provide first aid to any injured

16. Preliminary Actions • The priorities are: • save and preserve life • provide first aid to any injured • arrest, detain, and remove any suspect present

17. Preliminary Actions • Ensure that the scene is safe for investigators and forensic examiners to enter

18. Preliminary Actions • Ensure that the scene is safe for investigators and forensic examiners to enter • Secure and preserve the crime scene

19. At the Scene….. • Secure and preserve the crime scene by:

20. At the Scene…. • Secure and preserve the crime scene by: • keeping a record of anyone who enters or leaves

21. At the Scene…. • Secure and preserve the crime scene by: • keeping a record of anyone who enters or leaves • record and preserve evidence

22. At the Scene…. • Secure and preserve the crime scene by: • keeping a record of anyone who enters or leaves • record and preserve evidence • identify and locate any witnesses and keep them separate until statements have been taken

23. At the Scene…. • Secure and preserve the crime scene by: • keeping a record of anyone who enters or leaves • record and preserve evidence • identify and locate any witnesses and keep them separate until statements have been taken • communicate with the senior officer who is investigating

24. Once the scene has been secured……. • Lead investigator will

25. Once the scene has been secured……. • Lead investigator will • evaluate the area

26. Once the scene has been secured……. • Lead investigator will • evaluate the area • establish boundaries

27. Once the scene has been secured……. • Lead investigator will • evaluate the area • establish boundaries • determine the perpetrator’s path of entry and exit

28. Documentation • Three methods of crime scene recording are: • 1. photography

29. Documentation • Three methods of crime scene recording are: • 1. Photography • 2. Sketches

30. Documentation • Three methods of crime scene recording are: • 1. Photography • 2. Sketches • 3. Notes

31. Photography • A good photographic record helps: • a. Document the facts and physical circumstances of the scene

32. Photography • A good photographic record helps: • a. Document the facts and physical circumstances of the scene • b. Record evidence that cannot be easily brought to court

33. Photography • c. Permit reconstruction of the crime

34. Photography • c. Permit reconstruction of the crime • d. Reveal evidence that otherwise might have been missed

35. Photography • c. Permit reconstruction of the crime • d. Reveal evidence that otherwise might have been missed • e. Serve to refresh the investigator’s mind at any time

36. Photography • To be effective, photography should meet certain fundamental criteria:

37. Photography • To be effective, photography should meet certain fundamental criteria: • 1. It should occur immediately-- before other stages of the investigation

38. Photography • To be effective, photography should meet certain fundamental criteria: • 1. It should occur immediately-- before other stages of the investigation (scene must be in an untouched condition)

39. Photography • 2. Each scene should be photographed as completely as possible and be documented into notes and the sketch.

40. Photography • Photographs should include • a. Area where crime took place, as well as any adjacent areas • b. Points of entry and exit

41. Photography • Photographs should include • a. Area where crime took place, as well as any adjacent areas • b. Points of entry and exit • c. Various angles

42. Photography • Photographs should include • a. Area where crime took place, as well as any adjacent areas • b. Points of entry and exit • c. Various angles • d. All walls and adjacent rooms (if inside)

43. Photography • e. Position and location of evidence and/or body relative to the entire scene

44. Photography • e. Position and location of evidence and/ or body relative to the entire scene • f. Close-ups of injuries, weapons, and other physical evidence

45. Photography • e. Position and location of evidence and/or body relative to the entire scene • f. Close-ups of injuries, weapons, and other physical evidence • g. Surface under body after it is moved

46. Photography • e. Position and location of body relative to the entire scene • f. Close-ups of injuries, weapons, and other physical evidence • g. Surface under body after it is moved

47. Photography • h. All bloodstains • i. all latent fingerprints after dusting and before they are lifted

48. Photography • The use of videotaping is also becoming increasingly popular as an alternative to photographs.

49. Sketches • Sketches are made after the photographs by the crime scene investigator • Complements the photos and notes made at the scene.

50. Sketches • Sketches have several advantages: • 1. can display areas photos cannot (ie. floor plan)