1. Crime Scene Documentation
Evidence Collection:
Crime Scene Documentation

2. Methods of Documentation
The purpose is to record and preserve the location and relationship of discovered evidence & the condition of the crime scene .
4 methods
Reports and note-taking (sometimes audio)
Photographs
Vidography
Crime Scene Sketching

3. Crime Scene Sketching
Is a permanent record of the size and distance relationship of the crime scene and the physical evidence within it.
Usually drawn from an overhead perspective
2 types are produced
Rough sketch
Final sketch

4. Rough vs Final Rough: Developed while at the scene Not done to scale
Used to record size measurements of items and structures
Also record distance measurements between items and structures
Final:
Polished version of the rough sketch
Drawn to scale
Completed in the office
Only items and structures deemed significant to the case will be included
Must include all proper documentation in labeling

5. Labeling of Final Sketch
Title – ex: ABC Bank Robbery
Legend – “key” depicting what each symbol in the sketch means
Case information – date, time, place, case #
Name – name of person who drew the sketch
Indication of direction (N-S-E-W)
Scale – ex: 1 inch = 1 foot

6. 5 Basic Sketch Techniques
Triagulation Mapping
Polar Coordinate Mapping
Baseline Mapping
Rectangular Coordinate Mapping
Advanced Mapping Techniques

7. Triagulation Mapping
Based on the measurements of the three sides of a triangle.
Most accurate method that does not use advanced technology.
Laborious and time consuming

8. Polar Coordinate Mapping
Provides angle distance measurements from a fixed or known point
Best for large outdoor areas with few landmarks

9. Baseline Mapping Most basic Least accurate
All measurements are made in reference to one straight line within the crime scene
Error comes from measurements not being taken at exactly 90º angle from the reference line

10. Rectangular Coordinate Mapping *Method we will use in class*
Uses two baselines for which to reference every object to
More accurate than single Baseline Technique

11. Advanced Mapping Techniques
Uses modern technology such as global positioning systems (GPS)
Helpful for mapping large-scale scenes