1. The Proper way to identify, process and preserve evidence
The Crime Scene
The Proper way to identify, process and preserve evidence

2. First and Most important
Preserve the crime scene, if it has not already been done so.
Tape it off and restrict access to necessary personnel ONLY!!
Remember Locard’s Principle. The more people who come in and out of the crime scene, the more they destroy crucial evidence, leave and/or leave behind deceptive evidence of their own

3. Strike a Pose Photograph/Video the scene
When arriving at a crime scene, take photos starting from point of arrival to the actual crime scene.
This should be done before any moving or examining of evidence

4. Benefits of Photography
Forever preserves the scene
Catches details that even the most detailed investigator would miss
Some of the strongest evidence presented in court

5. Evidence Collection
Place evidence markers at each item that might be evidence (ex. Blood, clothing, weapons, bodily fluids etc)
Place Photo Evidence Ruler near each piece of evidence that needs size determination.
Now retake photos with evidence markers and rulers.

6. How To Photograph Evidence with a Ruler
Picture must be taken perpendicular to the plane that the evidence is lying on.
Ruler must fit within the viewfinder of the camera along with the evidence.

7. For this we use evidence markers
At the Scene
The goal of the evidence collection stage
Recreate the crime scene or Modus Operandi- to recreate the sequence of events
Find, collect and
preserve all physical
evidence
For this we use evidence markers

8. Take Notes Be meticulous!!!
It is important that you write down everything you observe
This includes but is not limited to:
The body
Ballistics and Tools marks
Blood
Trace Evidence
Etc.
Be meticulous!!!

9. So don’t forget your compass and tape measure
Start Sketching
So don’t forget your compass and tape measure
Draw a rough sketch of the scene
Be sure to include the location of furniture, identified evidence (including the body), windows, doors, etc.
Measure the distances of major objects in the room in relationship to two fixed points (Corner of a Room or if outside, major landmarks)
Include measurements and directional references on your sketch (North, South, etc.)

10. Rough Draft
Must have measurements of room and measurements of location of evidence in reference to your fixed point.

11. Final Draft

12. Legends Needed Each room can be labeled with a letter (A1-body)
5’’S, 3’’E
A2 (knife)
6’’S, 2’’E
B1 (GUN)
8’’S, 20”E
C3 (bloody sock)
2’’S, 7”E

13. Go for the Body!! It is crucial that you examine the body efficiently.
Examine the body for evidence on skin, clothing and the immediate surrounding area
Careful not to disturb the evidence until you are ready to collect the samples

14. Processing patterns
The outward spiral search: The CSI starts at the center of scene (or at the body) and works outward.
Especially good for under water crime scenes.

15. Processing patterns
The parallel search: All of the members of the CSI team form a line. They walk in a straight line, at the same speed, from one end of crime scene to the other.
Mostly used for large outdoor areas or fields.

16. Processing patterns
With all walk through methods, be cautious not to step on any possible evidence
The inward spiral search: The CSI starts at the perimeter of the scene and works toward the center. Spiral patterns are a good method to use when there is only one CSI at the scene.

17. Processing patterns
The grid search: A grid search is simply two parallel searches, offset by 90 degrees, performed one after the other.

18. Processing patterns
The zone search: In a zone search, the CSI in charge divides the crime scene into sectors, and each team member takes one sector. Team members may then switch sectors and search again to ensure complete coverage.

19. Aerial Search
Is a search conducted by a fixed wing aircraft or helicopter. Useful for searches covering large expanses of land.

20. Can’t Find Evidence Have alternate search groups
Alternate searchers within the groups
Utilize all of your resources.

21. After Your Search is Over
Check it again
Don’t forget to LOOK UP!!!

22. Crime Scene Activity
At your table you will find a mini mock crime scene. Remember what you learned the day before, don’t touch anything. With index cards, make your own evidence markers. You will be creating a crime scene sketch. Choose a reference point.
Grab a meter stick for measuring.
BEGIN!!!!!!!

23. Lets See How We Did : )

24. Evidence Collection

25. Potential Sources of DNA Evidence
Food
Bottles or Cans
Gloves
Watches
Condoms
Used Tissues
Handkerchiefs
Cigarette buds
Clothing
Hat
Eyeglasses
Earrings
Chewing Gum
Tooth Picks
Tooth Brushes
Bite Marks
Licked Stamps/Envelopes

26. “Touch” or “Trace” DNA Sources
Casual contact between a person’s hand(s) and an item
Almost anything can possess touch DNA
Must be careful about cross contamination and mixtures
Recovery of touch DNA is accomplished through swabbing.

27. Caution Regarding “Touch” DNA
Carefully weigh the value of a possible latent print against a possible DNA profile
“Touch” DNA is not meant to replace latent prints.

28. Collecting and Recovering DNA Evidence
Swabbing
Cutting
Scraping
Tape Lift
Collecting the Entire Object

29. Collection of Semen Evaluate the stain and its probative value
Swab the stain-Works best on non-absorbent surfaces
Cut the stain from the item
Collect the item

30. Collection of Semen: Condoms
If the condom appears ‘filled’
Secure the condom if possible so the inside doesn’t contaminate the outside
Tie off open end of condom
Individually package

31. Collection of Hair and Fibers
Lift with tape
Use gloves or forceps to transfer hair/fibers into a paper bindle
Placing hair straight into a bag is NOT recommended due to static electricity

32. Collection of Saliva
Saliva can be found on bitemarks, food, drinks, or toothbrushes
Recovery:
Lightly moisten swabs
Rotate and swab area
Allow samples to air dry

33. Known Saliva (Buccal) Swabs
Swab the inside of the cheek area using 2 swabs
Rotating them during collection (approx seconds)
Allow swabs to air dry and package together in paper

34. Fingernail Scrapings/Clippings
Collect only when indicated
Clip nails into clean paper with a clean clipper
Separating left and right nails OR
Scrape the underside of each nail onto a clean paper
Package the scrapings inside this paper

35. Packaging of Evidence
Dry items should be packaged in porous containers such as paper bags, envelopes, boxes

36. Packaging of Wet Items
Wet items should be allowed to air dry prior to packaging
Very wet items can be transported in plastic containers but should be air-dried as soon as possible

37. Packaging Materials Paper bags Pill boxes Envelopes
Druggist fold envelopes
Glass jars
Paint cans
Cardboard boxes

38. Packaging Techniques Choice of proper container:
Paper is the packaging material of choice
Plastic should only be used to transport evidence
Allow evidence to air dry prior to submitting into evidence

39. Packaging Techniques
Package items separately when recovered separately
If items found together, then package together
Clothing in a pile
Cigarettes in an ashtray

40. Packaging Techniques
Minimizing interior movement will help protect DNA evidence from being removed by being wiped away

41. Labeling Packages Name/initials of the collector
Each person/entity subsequently having custody
Date of collection or transfer
Agency and case#
Victim or suspect name
Brief description of item

42. Labeling Packages Label and identify exterior as to contents
Every level of packaging gets identifying information

43. Labeling Packages
Label the item with warnings/hazards or other helpful information;
Biohazard
Sharp
Fragile
Unloaded
Etc.

44. Sealing the Package Seal the package with tape
Prevents items from falling out
Provides measure of security-evidence cant be assessed unless seal is broken
Seals can be accomplished with packaging tape or evidence tape
Initial and Date across seal

45. Sealing the Package Acceptable Unacceptable Scotch Tape Packaging tape
Evidence tape
Unacceptable
Masking Tape
Staples