Principles of Exchange
Director of the world's first forensic lab in Lyon, France. Developed the Locard Exchange Principle.
Who is Dr. Edmond Locard?
Narrows an identity to a group of people or things.
What is Class Evidence?
Photographing the crime scene, close-up photo of evidence.
What is step 4, seeing the scene?
These are the first responders that secure the crime scene.
Who are Police Officers?
Evidence that is captured via a recording device
What is direct evidence?
The location where the crime scene took place.
What is primary crime scene?
Material that is transferred when one person comes in contact with another.
What is trace evidence?
Narrows an identity to a single person or thing.
What is Individual Evidence?
Using a pattern to ensure all evidence is secure.
What is step 6, searching for evidence?
These individuals document, collect evidence, record, and photograph the crime scene.
Who are Crime-Scene Investigators?
Indirect evidence used to imply a fact but not prove it directly.
What is circumstantial evidence?
Evidence that (if true) proves an alleged fact, such as an eyewitness account of a crime.
List 3 examples of trace evidence.
What are hair, fingerprints, soil, blood, tissue, or fibers?
Two types of circumstantial evidence.
What are biological and physical evidence?
This step involves safety, securing evidence, and logging requests for additional help.
What is step 1, secure the scene?
This individual determines the cause of death.
Who is a Medical Examiner?
The documented and unbroken transfer of evidence.
What is chain of custody?
A location other than the primary crime scene, but that is in some way related to the crime, where evidence is found.
Explain the Locard Exchange Principle.
What is when a person comes in contact with another person or object a cross-transfer of physical evidence can occur?
What are 2 examples of biological evidence?
Includes bodily fluid, hair, and natural fibers.
This step involves creating a rough sketch to include all evidence, fixed points and directions, and all information to complete a final sketch.
What is step 5, sketching the scene?
This person looks for leads & interviews witnesses.
Who is a detective?
This step involves determining the primary and secondary crime scene.
What is step 3, scanning the scene?
A small but measurable amount of physical or biological material found at a crime scene.
What is trace evidence?
Determines the amount of evidence that may be transferred in the Locard Exchange Principle.
What is the extent of contact?
What are 2 examples physical evidence?
Includes fingerprints, tire impressions, fiber, bullet casings.
This step involves questioning witnesses individually to avoid collusion.
What is step 2, separating the witnesses?
This person may be consulted if evidence requires his or her expertise.
Who is a specialist?
This step involves establishing a chain of custody and properly packaging evidence.
What is Step 7, secure and collect evidence?
What happens to the evidence if the collection protocols are not followed correctly?
The evidence may not be used in court