Chemistry 113: Forensic Science Introduction - PowerPoint PPT Presentation


PPT – Chemistry 113: Forensic Science Introduction PowerPoint presentation | free to download - id: 58e8a2-NTE3M


The Adobe Flash plugin is needed to view this content

Get the plugin now

View by Category
About This Presentation

Chemistry 113: Forensic Science Introduction


Chemistry 113: Forensic Science Introduction Prof. J. T. Spencer Adjunct Prof. T. L. Meeks Voire Dire ... – PowerPoint PPT presentation

Number of Views:594
Avg rating:3.0/5.0
Slides: 52
Provided by: Tyna
Learn more at:


Write a Comment
User Comments (0)
Transcript and Presenter's Notes

Title: Chemistry 113: Forensic Science Introduction

Chemistry 113 Forensic Science Introduction
  • Prof. J. T. Spencer
  • Adjunct Prof. T. L. Meeks

Course Description
  • Course Description and Prerequisite Skills
    Forensic Science is focused upon the application
    of scientific methods and techniques to crime and
    law. Recent advances in scientific methods and
    principles have had an enormous impact upon law
    enforcement and the entire criminal justice
    system. In this course, scientific methods
    specifically relevant to crime detection and
    analysis will be presented. No prior chemistry
    instruction is required or assumed but

CHE 113 2
Course Description
  • the course should appeal to those who have also
    had high school chemistry. Emphasis is placed
    upon understanding the science behind the
    techniques used in evaluating physical evidence.
    Topics included are blood analysis, organic and
    inorganic evidence analysis, microscopic
    investigations, hair analysis, DNA, drug
    chemistry and toxicology, fiber comparisons,
    paints, glass compositions and fragmentation,
    fingerprints, soil comparisons, and arson
    investigations, among others.

CHE 113 3
  • Lectures The material covered in class meetings
    will be illustrative rather than exhaustive. You
    should read the material in the text or handouts
    assigned before the class meeting. In class,
    alternate ways of understanding the material will
    often be presented. The examinations, however,
    will cover both the assigned text and lecture
    materials (whether or not they are specifically
    covered in class). Plenty of help is available
    in class meetings to answer questions and provide
    assistance with problems.

CHE 113 4
  • In-Class Materials The material covered in
    class is illustrative rather than exhaustive.
    You should read the material in the text assigned
    before the class. In class, alternate ways of
    understanding the material will often be
    presented. The examinations, however, will cover
    both the assigned text and in-class materials
    (whether or not they are specifically covered in

CHE 113 5
  • Grading and Examinations Final grades will be
    assigned based upon the hourly exams given during
    each quarter in the regularly scheduled class
    (50), the final examination an average of a
    midterm in January and a final in June (25 ),
    and the laboratory grade (25 ) as follows
    projects will be counted as exam grades in the
    quarter in which they are presented
  • Hourly Examinations and Projects 50
  • Final Examination average 25
  • Laboratory 25
  • 100
  • There will be NO MAKE-UP Examinations.

CHE 113 6
Quarter Projects
  • First Quarter Project Forensic Professionals
  • Pick any topic in forensic science.  You will be
    presenting this topic to the class in the form of
    a 5 minute power point presentation.  The object
    is to familiarize yourself, as well as your
    classmates, on this topic.  The power point
    should include all necessary pictures, drawings,
    vocabulary etc.  You will provide the narrative. 
    Remember this is a presentation, you are not
    using the power point as a teleprompter to read
    from.  Provide your resources on one of the last
    slides.  Write 5 test questions on your
    presentation either fill-in or short answer
    style with the answers.
  • Topic and abstract submission due Friday
    September 20 TYPED.
  • Project due date TBA (second week in October)

CHE 113 7
Quarter Projects
  • First Quarter Project Forensic Professionals
  • Description of profession
  • How that profession fits into Forensics
  • What is the degree/credentials needed for that
    profession (possible salary)
  • Are you still interested in this as a profession
  • Works cited

CHE 113 8
Quarter Projects
  • Second Quarter Project Innocence Project
    Research and paper
  • You will be exploring the Innocence Project
    online and answering questions as you move
    through the website. The questions will give you
    background needed to create an opinion paper
    concerning the Innocence Project

CHE 113 9
Quarter Projects
  • Third Marking Period Project
  • Drug Project
  • Topic submission due TBA
  • Projects due TBA

CHE 113 10
Quarter Projects
  • Fourth Marking Period Project
  • Mock Trial
  • Projects due TBA

CHE 113 11
  • Required Textbooks The required textbook for
    this course is The Science of Criminalistics
    (Introduction to Forensic Science) by James T.
    Spencer to be published this year. Since the
    hardcopy of the text will not be ready by this
    summer, students can get to the chapters (free as
    pdfs) at and then click on Moodle
    (bottom of the page).  To logon, they use
    USERNAME forensics113 and PASSWORD Orange113
    (no spaces)

CHE 113 12
  • Laboratory There will be no Make-Up labs. In
    order to pass, a student must have a passing
    grade in the laboratory portion of the course.
    Attendance in laboratory is mandatory. The
    laboratory periods are 3 hours in length and,
    while some experiments will not require the total
    allotted time for completion, students are
    expected to arrive promptly at the beginning of
    the lab period and not leave until that
    particular experiment is completed and turned in.
    Students that arrive too late to complete the
    experiment in the allotted time and those that
    arrive on time but depart before turning in their
    lab reports will receive a zero for the

CHE 113 13
Chapter 1 Introduction, Historic Development, and
Legal Roles of Forensic Science
  • Prof. J. T. Spencer
  • Adjunct Prof. T. L. Meeks

Learning Goals and Objectives
  • Today, the role of science in the courtroom is
    undisputed. We rely upon the scientific analysis
    and interpretation of key evidence to both
    exonerate and convict. But this hasnt always
    been true in history. In this chapter an
    introduction to the role that forensic science
    has and does play in criminal justice is
    presented. Also, the legal underpinnings of the
    admissibility, use, and limitations of scientific
    evidence and testimony are explored. In this
    chapter, you will need to understand the
    following concepts

CHE 113 15
Learning Goals and Objectives
  • What is meant by the terms forensic science and
  • What is the difference between a basic and an
    applied science
  • What is the relationship between the law, basic
    science and applied science
  • How has forensic science developed throughout
    history to its present state
  • What is Locards Exchange Principle
  • How has fiction contributed to the development of
    forensic science
  • What features do fictional detectives and modern
    forensic scientists have in common

CHE 113 16
Learning Goals and Objectives
  • What is the CSI Effect and how has it influenced
    scientific evidence in the courtroom
  • What is meant by the Principle of Individuality
  • How do precedent cases pave the way for
    scientific evidence and testimony
  • What are the key features of the Frye and Daubert
  • How have the Joiner, Khumo and Melendez-Dias
    cases affected expert testimony.

CHE 113 17
Forensic Science
  • Forensic Science - Application of the scientific
    method and techniques to law and criminal
  • Lies at the point of convergence between our
    legal and scientific systems
  • The Law wants certainty
  • The Science can only establish the simplest of
  • Encompasses many fields...

Forensic Science
  • Advances in Forensic Science occur in unexpected
    leaps rather than small steps
  • The underlying science has been further developed
  • Technology has been created
  • Changes in legal policy or practice
  • Revolutionary rather than evolutionary

Forensic Science
Scientific Method- real science does not have to
follow steps IN ORDER.
Forensic Science
Scientific Evidence in Court
  • Scientific (Forensic) evidence is aimed at
    informing the court where it lack expertise.
  • Assist in determining fact.
  • What is admissible evidence?
  • Real Science vs Pseudo (Quack) Science
  • Established how to determine the difference
    through 4 primary cases (Frye, Daubert, Joiner,
    and Kuhmo)

Forensics in Court
The Jury Decides
  • How does a lay jury sort out real science from
    pseudo science?
  • Until 1923 individual courts could define what
    was acceptable as evidence in the courtroom.
  • Charisma
  • Ability to convince the jury

Forensics in Court
Frye Standard
  • 1923, polygraph evidence
  • the evidential force of the principle must be
    recognized, and while the courts will go a long
    way in admitting expert testimony deduced from
    well-recognized scientific principle or
    discovery, the thing from which the deduction is
    made must be sufficiently established to have
    gained general acceptance in the particular field
    in which it belongs.
  • Sets up the scientific field as the vaildator
    for legal admissibility while court determines if
    principles are generally accepted.

CHE 113 24
Forensics in Court
What is general acceptability?
  • Technique must be accepted by a meaningful
    segment of the relevant scientific community
  • Books
  • Papers
  • Prior judicial decisions
  • Length of existence of technique
  • Inflexible (and slow) for new developments or
    extensions of existing techniques and methods

Forensics in Court
Daubert case
  • 1993, Birth defects were caused by prenatal
    ingestion of Bendectin made by Merrill Dow.
  • The District Court granted Dow summary judgment
    based on expert testimony that said that maternal
    use of Bendectin had not been shown to be a risk
    factor for human birth defects. Although Daubert
    had the testimony of eight other experts who
    based their conclusions that Bendectin can cause
    birth defects on animal studies, chemical
    structure analyses, and the unpublished
    "reanalysis" of human statistical studies, the
    court determined that this evidence did not meet
    the applicable "general acceptance" standard for
    the admission of expert testimony. The Court of
    Appeals agreed and affirmed, citing Frye.
  • Supreme Court - The Federal Rules of Evidence,
    not Frye, provide the standard for admitting
    expert scientific testimony in a federal trial.

Forensics in Court
What are the Federal Rules of Evidence?
  • Based upon Federal Rules of Evidence (Rule 702)
    that are more flexible.
  • If scientific knowledge will assist the tryer
    of fact to understand evidence or to determine a
    fact in an issue, a witness qualified as an
    expert by knowledge, skill, experience, training,
    or education, may testify..if
  • It is based upon sufficient fact or data
  • It is a product of reliable principles and
  • The principles are applied reliably to the facts
    of the case.

Forensics in Court
Judge is the Gatekeeper
  • General acceptance of Frye standard not
  • Assigns trial judge gatekeeper responsibilities
    in determining the admissibility and reliability
    of scientific evidence. (Daubert Hearings)
  • More Flexible in admitting new types of data
  • Relies upon jury (with help from the judge) to
    determine value of evidence and the adversarial
    judicial system (cross-examination of expert
    witnesses and counter expert witnesses) to refute
    scientific evidence.

Forensics in Court
How does the judge decide?
  • Guideline for determining value of scientific
    evidence may include
  • Has the technique or theory been tested
  • Has the technique or theory been subjected to
    peer review
  • What is the techniques potential error rate
  • Existence of standards controlling the
    performance of the analysis
  • Has the theory or method received widespread
    acceptance within the appropriate community
  • Allows for authentic scientific break-throughs

Forensics in Court
  • 1995 -Case asserted that PCBs caused cancer in
  • Tried to establish a causal link between PCBs
    and cancer based upon animal models.
  • Conclusions and methodology are not separate.
    Experts commonly extrapolate from existing data
    but nothing requires a court to admit opinion
    evidence that is connected to the data only by
    the expert themselves.
  • The court may conclude that there is too great a
    gap between the data and the opinion.

Forensics in Court
Kumho Tire Case
  • 1999 - Tire blowout liability case.
  • Plaintiff expert wanted to testify that the
    blowout was due to defect rather than
  • Did not allow plaintiff expert testimony since
    the test by the expert was unreliable and made
    up by him (i.e., baseball batter designing his
    own strike zone).
  • make certain that an expertemploys the same
    level of intellectual rigor that characterizes
    the practice of an expert in the relevant field.
  • Supreme Court extended Daubert's holding to
    include non-scientific expert testimony.

Voire Dire
  • http//

Forensics in Court
  • Federal Courts use Daubert Standard
  • Many State Courts use Daubert
  • About Half of State and Most Local Courts still
    use Frye.

Forensic Science History
  • Began formally in late 1700s.
  • Real application of the scientific method and
    techniques developed in 1900s.
  • Important Names
  • Alphonse Bertillion (anthropometry)
  • Francis Galton (Fingerprinting)
  • Calvin Goddard (Ballistics)
  • Alexandre Lacassagne (anthropology)
  • Edmond Locard (scientific criminal investigation)
  • Matheau Orfila (toxicology)
  • Crime Writers esp. A.C. Doyle, D.L. Sayers,

CHE 113 34
Alphonse Bertillion
  • (1853-1914) Physician and Statistician
  • devised a system of identification of criminals
    that relies on 11 bodily measurements and the
    color of the eyes, hair, and skin

Francis Galton
  • (1822-1911)
  • Anthropologist and
  • Explorer
  • the author of memoirs on various anthropometric
    subjects he originated the process of composite
    portraiture, and paid much attention to
    fingerprints and their employment for the
    identification of criminals

Calvin Goddard
  • (1891-1955)
  • Pioneer in Forensic Ballistics
  • brought professionalism, the use of the
    scientific method, and reliability to Forensic
    Firearm Identification, at a time when
    charlatanism was rampant in this field

Alexandre Lacassagne
  • (1843-1924) Professeur de médecine légale à la
    Faculté de Lyon, Alexandre
  • Criminal Anthropology

Edmond Locard
  • 1877-1966 - Application of scientific techniques
    to criminal investigations.
  • Set up first real forensics lab and developed the
    first fundamental principle of forensic science

Locards Exchange Principle
  • The most basic concept of Forensic Science
  • When contact with an object or person occurs, a
    cross transfer of evidence occurs
  • Examples dust, biological samples, fingerprints,
    chemical residues, etc.
  • Can be used as evidence based on the Principle of
  • Two objects may be indistinguishable, but no two
    objects are ever identical. Things can at least
    be put in classes or even individualized in
    useful ways.

Matheau Orfila
  • 1787-1853 Professor of Chemistry in the faculty
    of Medicine at Paris.
  • Traité des poisons or Toxicologie générale (1813)
    - published at the age of 27

His first publication was a vast mine of
experimental observation on the symptoms of
poisoning of all kinds, on the appearances which
poisons leave in the dead body, on their
physiological action, and on the means of
detecting them
Arthur Conan Doyle
  • Creator of Sherlock Holmes - Based upon Poes
    Dupin and real life Prof. Joe Bell (U.
  • Preceded and foretold many chemical analyses for
    forensic investigations

CSI Effect
The general public is now not only comfortable
with forensic evidence as never before, they
actually seek out opportunities to test their
forensic skills with whodunits. The
expectation and the demand by the general public
regarding the information that forensic science
can provide, often by exaggerating to impossible
levels the role that forensic science plays in
cases, has been risen tremendously
CSI Effect
CSI Effect Definition of CSI Effect (Nolos Plain
English Law Dictionary) A phenomenon reported
by prosecutors who claim that television shows
based on scientific crime solving have made
actual jurors reluctant to vote to convict when,
as is typically true, forensic evidence is
neither necessary nor available. In a recent CSI
Effect study (N.J. Schweitzer and M.J. Saks
Jurimetrics Vol. 47, p. 357, 2007) Compared to
non-CSI viewers, CSI viewers were more critical
of the forensic evidence presented at the trial,
finding it less believable. Regarding their
verdicts, 29 of non-CSI viewers said they would
convict, compared to 18 of CSI viewers.
Crime Labs
  • Earliest crime lab was founded by Edmond Locard
  • Evolution of Crime Lab
  • http//
  • New York State Troopers Forensic Lab
  • http//
  • Approximately 320 public crime labs operate at
    various levels of govt federal, state, county,
    and municipal

Rationale for Crime Labs
  • The increasing volume of physical evidence
    recovered from crime scenes was a result of
    rising crime rates.
  • The need to perform chemical analyses on drugs,
    coupled with a significant increase in illicit
    drug seizures.
  • Supreme Court decisions have enhanced the rights
    of the defendant. Decisions, such as those
    insuring a defendants right to counsel and the
    right to remain silent, have encouraged police
    agencies to place a greater reliance on
    scientific investigative techniques.
  • Advances in scientific technology have provided
    forensic scientists with many new skills and
    techniques to extract meaningful information from
    physical evidence.

Incorporating evidence collection into crime labs
Crime Lab
  • Before evidence can be properly analyzed it must
    be recognized, collected and properly packaged at
    the crime site.
  • Evidence technicians under the continuous
    direction of the crime laboratory are more likely
    to have received thorough training in the
    gathering of evidence at the crime site.
  • Evidence technicians, who are continuously
    exposed to the problems and techniques of the
    forensic scientist, are better prepared to adopt
    new procedures or modify existing procedures to
    improve evidence collection.

Services of Crime Lab
  • -Biology Unit
  • -Firearms Unit
  • -Document Examination Unit
  • -Photography Unit
  • -Toxicology Unit
  • -Latent Fingerprint Unit
  • -Polygraph Unit
  • -Voiceprint Analysis Unit
  • -Evidence-Collection Unit
  • -Forensic Anthropology
  • -Forensic Entomology
  • -Forensic Psychiatry
  • -Forensic Odontology
  • -Forensic Engineering

Dynamic Duo of Principles
  • Locards Principle
  • When two objects come into contact, some
    materials or information is transferred between
    the two.
  • If this transferred evidence can be found, then
    the connection between the two can be established.

CHE 113 49
Dynamic Duo of Principles
  • Principle of Individuality
  • Even though two objects may be indistinguishable,
    they can never be exactly identical.
  • While we might not be able to tell the difference
    between two objects, at some level maybe even
    only at the atomic or molecular level they must
    be different.
  • We should be able to determine whether two
    samples came from one original source or from two
    completely separate sources.

CHE 113 50
  • 1.1 What is forensic science?
  • 1.2 What is the Daubert standard?
  • 1.3 What is Locards Exchange principle?
  • 1.4 What is meant by the CSI Effect when it
    comes to jury expectations during a trial?
  • 1.5 What is the Principle of Individuality?
  • 1.6 What is meant by a precedent case? Give
    examples of precedent cases and explain their
  • 1.7 How did the Frye decision of 1923 impact the
    admissibility of forensic evidence?
  • 1.8 What standard replaced the Frye standard and
    how did it change the use of forensic evidence
    at trial?
  • 1.9 List and explain the three parts of the
    Daubert standard.
  • 1.10 Explain the importance of the Joiner (1995)
    and Khumo (1999) cases as they pertain to
    forensic testimony.

CHE 113 51