1. Locard’s Principle Abby and the pollen\

2. Edmond Locard - Biography
1877 – birth of Edmond Locard
1902 – Locard obtains his PhD in medicine
1907 – Locard passes his bar examine
1908 – Locard starts his world travel
1910 – Locard creates the ancestor of the crime laboratory in Lyon, France
1912 – official creation of the crime lab in Lyon
Locard starts his writings and will produce more that 40 publications
1966 death of Edmond Locard

3. Locard’s Bibliography
In French, English, German, and Spanish
More than 40 publications (books and articles)
Criminalistics
Philately (stamps)
Police Investigation
Police and Forensics Novels

4. Locard’s Contribution
“He put the analysis of handwriting on a firmer footing, systematized the analysis of dust in the clothes of suspects, invented a modified method of analysis of blood stains, and invented poroscopy, whereby the pores in papillary ridges of fingerprints are used as a mean of identification.”
Harry Soderman (1957) Policeman’s Lot

5. Locard’s Exchange Principle
“Toute action de l’homme, at a fortiori, l’action violoente qu’est un crime, ne peut pas se dérouler sans laisser quelque marque.” Any action of an individual, and obviously, the violent action constituting a crime, cannot occur without leaving a trace.

6. Crime Scene Basics Forensic Science
T. Trimpe

7. Crime Scene Vocabulary
CRIME SCENE: Any physical location in which a crime has occurred or is suspected of having occurred.
PRIMARY CRIME SCENE: The original location of a crime or accident.
SECONDARY CRIME SCENE: An alternate location where additional evidence may be found.
SUSPECT: Person thought to be capable of committing a crime.
ACCOMPLICE: Person associated with someone suspected of
committing a crime.
ALIBI: Statement of where a suspect was at the time of a crime.
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8. What will evidence collected at a scene do for the investigation?
Types of Evidence
Testimonial evidence includes oral or written statements given to police as
well as court testimony by people who witnessed an event.
Physical evidence refers to any material items that would be present
at the crime scene, on the victims, or found in a suspect’s possession.
Trace evidence refers to physical evidence that is found in small but
measurable amounts, such as strands of hair, fibers, or skin cells.
What will evidence collected at a scene do for the investigation?
May prove that a crime has been committed
Establish key elements of a crime
Link a suspect with a crime scene or a victim
Establish the identity of a victim or suspect
Corroborate verbal witness testimony
Exonerate the innocent.
Give detectives leads to work with in the case
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9. Crime Scene Personnel
POLICE OFFICERS are typically the first to arrive at a crime scene. They are responsible for securing the scene so no evidence is destroyed and detaining persons of interest in the crime.
The CSI UNIT documents the crime scene in detail and collects any physical evidence.
The DISTRICT ATTORNEY is often present to help determine if any search warrants are required to proceed and obtains those warrants from a judge.
The MEDICAL EXAMINER (if a homicide) may or may not be present to determine a preliminary cause of death.
SPECIALISTS (forensic entomologists, anthropologists, or psychologists) may be called in if the evidence requires expert analysis.
DETECTIVES interview witnesses and consult with the CSI unit. They investigate the crime by following leads provided by witnesses and physical evidence.
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10. Adapted from http://www.feinc.net/cs-proc.htm
Crime Scene Protocol
Step 1: Interview
The first step in investigating a crime scene is to interview the first officer at the scene or the victim to determine what allegedly happened, what crime took place, and how was the crime committed. This information may not be factual information but it will give the investigators a place to start.
Step 2: Examine
The second step in the investigation of a crime scene, which will help identify possible evidence, identify the point of entry and point of exit, and outline the general layout of the crime scene.
Step 3: Document
The third step in the protocol involves creating a pictorial record of the scene as well as a rough sketch to demonstrate the layout of the crime scene and to identify the exact position of the deceased victim or other evidence within the crime scene.
Step 4: Process
This is the last step in the protocol. The crime scene technician will process the crime scene for evidence, both physical and testimonial evidence. It is the crime scene technicians responsibility to identify, evaluate and collect physical evidence from the crime scene for further analysis by a crime laboratory.
Adapted from

11. Investigating the Evidence
Forensic Science disciplines at the Illinois State Police Crime Labs
Drug Chemistry – Determines the presence of controlled substances and the identification of marijuana
Trace Chemistry - Identification and comparison of materials from fires, explosions, paints, and glass.
Microscopy – Microscopic identification and comparison of evidence, such as hairs, fibers, woods, soils, building materials, insulation and other materials.
Biology/DNA – Analysis of body fluids and dried stains such as blood, semen, and saliva.
Toxicology – Tests body fluids and tissues to determine the presence of drugs and poisons.
Latent Prints - Identification and comparison of fingerprints or other hidden impressions from sources like feet, shoes, ears, lips or the tread on vehicle tires.
Ballistics (Firearms) – Study of bullets and ammunition through the comparison of fired bullets, cartridges, guns, and gunpowder patterns on people and objects.
Toolmarks – Examines marks left by tools on objects at a crime scene or on a victim, such as a hammer used to break a door or a screwdriver used to pick a lock.
Questioned Documents - Examination of documents to compare handwriting, ink, paper, writing instruments, printers, and other characteristics that would help to identify its origin.
Source:

12. What evidence would you collect?
Mock Crime Scene:

13. Special Forensic Science Services

14. Skills of a Forensic Scientist
A forensic scientist must be skilled in applying the principles and techniques of the physical and natural sciences to the analysis of the many types of evidence that may be recovered during a criminal investigation.
A forensic scientist may also provide expert court testimony.
An expert witness is an individual whom the court determines possesses knowledge relevant to the trial that is not expected of the average person.

15. Skills of a Forensic Scientist
The expert witness is called on to evaluate evidence based on specialized training and experience that the court lacks the expertise to do.
The expert will then express an opinion as to the significance of the findings.
Forensic scientists also participate in training law enforcement personnel in the proper recognition, collection, and preservation of physical evidence.

16. The Frye Standard
The Frye v. United States decision set guidelines for determining the admissibility of scientific evidence into the courtroom.
To meet the Frye standard, the evidence in question must be “generally accepted” by the scientific community.

17. Frye Not Absolute
However, in the 1993 case of Daubert v. Merrell Dow Pharmaceutical, Inc., the U.S. Supreme Court asserted that the Frye standard is not an absolute prerequisite to the admissibility of scientific evidence.
Trial judges were said to be ultimately responsible as “gatekeepers” for the admissibility and validity of scientific evidence presented in their courts, as well as all expert testimony.

18. Daubert Criteria For Admissibility
Whether the scientific technique or theory can be tested.
Whether the technique has been subject to peer review and publication.
The techniques potential rate of error.
Existence and maintenance of standards .
Whether the scientific theory or method has attracted widespread acceptance within a relevant scientific community.