1. September 5, 2012
Investigating a Crime
scene

2. 1. Initial assessment
• Identify any hazards
• Then make the area safe
• Determine if a crime has taken place
• Identify any victims
• Identify any witnesses and suspects (and keep
them apart)
09/05/12

3. 2. Securing the crime scene
• Preserve the scene as it was found
• Restrict access to avoid contamination
• Protect the scene – from weather, public,
media (TV)
• Common approach path ( single entrance)
09/05/12

4. contamination
• The presence of small amounts of substance
in another
• If one piece of evidence comes into contact
with another, small amounts can be
transferred
09/05/12

5. 3. Recording the scene
• Sketches
• Notes
• Photographs
• video
09/05/12

6. 4. Searching the scene
• Systematically
• Protective equipment ( also avoids
contamination)
• Mark location of evidence
09/05/12

7. Collecting fingerprints
• Why are these important?
• 3 types:
– Plastic – in a soft or wet substance eg putty
– Visible – from eg paint, chocolate, ink
– Hidden (latent) – from oil and sweat on skin
09/05/12

8. Basic fingerprint patterns
09/05/12

9. Taking fingerprints
• 1. Using ink, collect a set of prints using each
of your fingers
• 2. Identify the patterns you see
• 3. Collect some of the latent prints – using
carbon powder
• 4. Can you match the suspect to the scene of
the crime?
09/05/12