Crime Scene Search Patterns: Techniques and Strategies

1. Crime Scene Documentation August 16, 2020

2. Crime Scene search patterns • Investigators often use geometric search patterns while • searching for evidence to ensure that no evidence is missed. • The type of search pattern depends on the scene.

3. Crime Scene search patterns

4. Crime Scene search patterns • Grid search patterns • Effective, but time consuming • Best with well-defined boundaries • Can be done by 1-2 people

5. Crime Scene search patterns • Rarely used • Doesn’t work well around obstacles. • Sometimes used when only one investigator is present. Spiral Search Patterns

6. Crime Scene search patterns • In large outdoor area, parallel lines can be formed using volunteers spaced evenly apart and walking in the same direction. • Parallel lines can also be made (in smaller areas) by one or two volunteers. Parallel / Linear Search Patterns

7. Crime Scene search patterns • Works well in buildings or vehicles. • Often different team members will take different zones. Zone / Quadrant Search Patterns

8. Crime Scene search patterns • Think about the following, but DON’T say the answer out loud. When I ask, show me the correct answer with your fingers. • Investigators believe a body may have been dumped in a large field. What search pattern be used? • Spiral • Grid • Parallel • Zone

9. Crime Scene search patterns • Think about the following, but DON’T say the answer out loud. When I ask, show me the correct answer with your fingers. • Investigators believe a body may have been dumped in a large field. What search pattern be used? • Spiral • Grid • Parallel • Zone How do you know?

10. Crime Scene search patterns • Think about the following, but DON’T say the answer out loud. When I ask, show me the correct answer with your fingers. • A very high profile crime has been committed, and the police has been given a lot of resources and manpower to solve it. Which pattern is appropriate? • Spiral • Grid • Parallel • Zone

11. Crime Scene search patterns • Think about the following, but DON’T say the answer out loud. When I ask, show me the correct answer with your fingers. • A very high profile crime has been committed, and the police has been given a lot of resources and manpower to solve it. Which pattern is appropriate? • Spiral • Grid • Parallel • Zone How do you know?

12. Crime Scene search patterns • Think about the following, but DON’T say the answer out loud. When I ask, show me the correct answer with your fingers. • Police have a warrant to search a suspect’s car. Which pattern is appropriate? • Spiral • Grid • Parallel • Zone

13. Crime Scene search patterns • Think about the following, but DON”T say the answer out loud. When I ask, show me the correct answer with your fingers. • Police have a warrant to search a suspect’s car. Which pattern is appropriate? • Spiral • Grid • Parallel • Zone How do you know?

14. Crime Scene Notes • Investigators take detailed notes on all of the following: • Step-by-step description of every action taken by investigators. • Date, time, location, weather, environmental conditions • Description of crime • Location of evidence with reference to other fixed points • Names of all people on the scene, including authorized personnel, witnesses, victims

15. Example Note 1 What types of info do you see?

16. Example Note 2 What types of info do you see?

17. Crime Scene PHotos • The scene should be thoroughly photographed before • evidence collection. • Types of photos: • overall scene (exterior and interior) • midrange photos • close up • Use scales and numbered • placards with photos – why? Start with the larger, exterior scene, and move interior and towards finer detail.

18. Photo Example 1 What type of photo is this? What other photos should be taken?

19. Photo Example 2 What type of photo is this? What else would be useful in this photo?

20. Photo Example 3 • What type of photos are these? Which one is better and why?

21. Crime Scene Videos • Crime scenes should be videotaped starting outside and moving in, all around the crime scene. • Important details (time, place, and objective descriptions should be included, • Other narration should be avoided. • Should not include members of the investigative team. Watch me!

22. Crime Scene Sketches • Rough sketches are done on the scene, and finished, to-scale sketches are completed later. • Crime scene sketches should be labeled with: • A title • A legend with letters, etc., for key pieces of evidence • Compass direction • Whether to scale, and if so, what scale • Case number • Offense type • Location

23. Discuss with a partner:How do These differ?

24. Crime Scene Sketches • In order to record exactly where the evidence is located, each • and every piece of evidence must be measured from two fixed • points. • This is called triangulation. • In practice, this is often most • Easily done by recording the • ‘x’ and ‘y’ distances of every • piece of evidence in the room. Evidence Fixed point Y Fixed point X

25. Sketches – Practice • As a class, we will make a rough sketch of the room with 3 pieces • of evidence. • Our sketch needs to include: • Title block • Legend • Direction • Accurate measurements