Introduction to Forensic Science Evidence.ppt

Introduction to forensic science. History and standards of evidence collection.

1. Introduction to Forensic Science
Forensic Science A
Trimester 1
2019

2. Introduction to Forensic Science
•What does “forensic science” mean?
–Forensic- pertaining to, connected with, or
used in courts of law or public discussion and
debate
•The presentation of science or scientific
evidence in a public forum (court of law).

3. Sherlock Holmes (1887)
•Fictional character
developed by author Sir
Arthur Conan Doyle
•First to apply serology,
fingerprinting, firearm
identification, and
questioned-document
examination.
•All of this- from fiction-
before being accepted by
real-life criminal
investigation.

4. Mathieu Orfila- 1813
Father of Toxicology
•Lafarge Trial (Marie) arsenic
•Book: Traite des poisons or Toxicologie generale-
the first scientific study of the detection and
pathological effects of poisons- established
toxicology as a distinct field of forensic science

5. Alphonse
Bertillon- 1879
•The father of criminal identification
•Developed anthropometry- using
body length measurements as
unique properties- took 243 separate
measurements
•Method was coined “Bertillonage.”

6. What is Anthropometry?
•Greek
– Anthro- : man
– -pometry: measurements
–Literal meaning:
“measurement of humans”
•The study of
measurements or
proportions of the human
body according to sex,
age, etc. for identification
purposes
–Dimensions of bones,
muscles, and adipose (fat)
tissues

7. History of Anthropometry
•1883- Alphonse Bertillon: system of identification
depending on the unchanging character of
certain measurements of parts of the human
body
•1884: 241 multiple offenders were identified
•“Bertillonage”- first adapted by the French police

8. History of Anthropometry
•1888: Francis Galton
starts research on “Finger
Prints” to further
anthropometry
•1892: Francis Galton
publishes Finger Prints
•1903: Will West & William
West

9. Will vs. William West
•Will and William West were two inmates at Leavenworth
Penitentiary, shortly after the turn of the century.
 
•When he was received at Leavenworth, Will West denied previous
imprisonment there, but the record clerk ran the Bertillon
instruments over him anyway.
 He knew the reluctance of criminals
to admit past crimes.
 Sure enough, when the clerk referred to the
formula derived from West's Bertillon measurements, he located the
file of one William West, whose measurements were practically
identical and whose photograph appeared to be that of the new
prisoner.
•But Will West was not being coy about a previous visit to
Leavenworth.
 When the clerk turned over William West's record
card he found it was that of a man already in the Penitentiary,
serving a life sentence for murder.
 Subsequently the fingerprints of
Will West and William West were impressed and compared.
 The
patterns bore no resemblance.

10. Will vs. William West

11. Francis Galton
•Fingerprinting
–Developed methodology for identification
using the friction ridges on fingers
–Basics still used today
–His work has been enhanced by Sir Edward
Henry- the father of modern fingerprinting
–Henry developed a filing method for storing
fingerprint patterns/records prior to computer
storage capabilities

12. Edmond Locard
•Locard’s Exchange Principle- whenever
two objects come in contact, material will
be exchanged between them.
•Every criminal can be tied to crime by dust
particles carried from the scene
–Example: 90% of US Currency contains trace
amounts of cocaine

13. Evidence: What is it?
•Direct: evidence in the form of a statement
made under oath
•Also known as testimonial evidence
•Indirect: Physical Evidence- any object or
material that is relevant in a crime.
•Locard’s Principle
•Class vs. Individual Evidence

14. What is it good for?
•Physical Evidence
–Prove that a crime has
been committed
–Corroborate testimony
–Link suspect to a victim or
crime scene
–Establish identity of
persons associated with
crime
–Reconstruction of the crime

15. Class Evidence
•Class evidence is evidence that can be linked to a group
of people
•Consistent with a particular source
•The more class evidence that fits the criminal the better
•Examples of Class Evidence include:
–Hair - Fibers
–Soil - Glass Fragments
–Shoe Prints - Blood Type

16. Individual Evidence
•Individualized to a single, specific source
•There is almost no doubt as to what the
source is
–Fingerprints
–DNA
–Handwriting
–Voiceprints
•Always involves a comparison- an
exemplar

17. Mr. Houvener has been
FINGERPRINTED!!!
•No…. I didn’t have a
rough weekend
•All of your teachers
are required to have
fingerprints taken by
computer (Livescan)
prior to being
employed through
KPS

18. Rules of Evidence
•Admissible evidence must be
–Relevant- must prove something (probative)
and address the issue of the particular crime
(material)
–Reliable
–Presenter must be credible and competent

19. Scientific Evidence
•Frye Standard
–Interpretation of evidence must be given by
an expert witness & have gained “general
acceptance” in that particular field
–Frye vs. U.S., 1923: court must decide if the
handling of evidence are “generally accepted”
by a meaningful segment of the relevant
scientific community.

20. Scientific Evidence
•Daubert Ruling
–Jason Daubert and Eric Schuller had been born with serious
birth defects. They and their parents sued Merrell Dow
Pharmaceuticals Inc. claiming that the drug Bendectin had
caused the birth defects. Merrell Dow removed the case to
federal court, and then moved for summary judgment because
their expert submitted documents showing that no published
scientific study demonstrated a link between Bendectin and
birth defects. Daubert and Schuller submitted expert evidence
of their own that suggested that Bendectin could cause birth
defects. Daubert and Schuller's evidence, however, was
based on in vitro and in vivo animal studies, pharmacological
studies, and reanalysis of other published studies, and these
methodologies had not yet gained acceptance within the
general scientific community.
–The Ninth Circuit found the district court correctly granted
summary judgment because the plaintiffs' proffered evidence
had not yet been accepted as a reliable technique by
scientists who had had an opportunity to scrutinize and verify
the methods used by those scientists.

21. Daubert Ruling
–Applies to federal courts and SOME states
(including Michigan)
•Judge determines admissibility
–Guidelines for the Judge
1.Scientific theory or technique must be testable
2.Must be subject to peer review and publication
3.Rate of error must be stated
4.Technique must follow standards
5.Consideration as to whether there is widespread acceptance in
the scientific community.

22. Facets of Guilt
•Try to prove:
•Means—person had the ability to do the crime
•Motive—person had a reason to do the crime
(not necessary to prove in a court of law)
•Opportunity—person can be placed at the
crime