Download CHAPTER 1 – FORENSIC SCIENCE NOTES INTRODUCTION What

CHAPTER 1 – FORENSIC SCIENCE
NOTES
I.
INTRODUCTION
A. What is Science?
a. Derived from the Latin verb meaning “to know”
b. Science is a way of knowing
c. A systematic acquisition of knowledge that can be measured precisely
B. Discovery Science and Induction
a. Discovery Science = verifiable observations and measurements
1. Often discover by accident
2. Often give rise to inductive conclusions
b. Examples
1. Fleming, 1928, accidentally discovered that fungi produce
chemicals that kill bacteria. This led to the discovery of
Penicillin.
c. Induction
1. Inductive conclusion = a generalization that summarizes many
concurrent observations
1. Goes from specific observations to a generalization
2. Example: “all living things are made up of cells” arose
from 2 centuries of biologists discovering cells in all
biological specimens observed
C. Scientific Method
a. As a result of asking questions and seeking explanations
b. Is a formal process of inquiry, consisting of a series of steps
c. Hypothetico-deductive reasoning is used to answer the questions
1. Hypothesis = educated guess; explanation
2. Deductive = flows from the general to the specific instead of
from the specific to the general
3. Usually takes the place of predictions about outcomes of
experiments or observations
4. Is “If . . . Then” logic
d. Deduction and the Scientific Method
1. Observation : My flashlight doesn’t work
2. Question : What’s wrong with my flashlight?
3. Hypothesis: The flashlight’s batteries are dead
II.
4. Prediction: If this hypothesis is correct
5. Experiment: and I replace the batteries with new ones
6. Predicted Result: then the flashlight should work
e. If the result supports the hypothesis, make additional predictions and test
them
f. If result does not support hypothesis, revise hypothesis or pose new one
D. Forensic Science
a. Forensic = (adj). Pertaining to legal proceedings or public debate
b. Forensic Science = application of science to the processes of law and
involves the collection, examination, evaluation, and interpretation of
evidence
c. Application of …
1. Biological
2. Physical
3. Chemical
4. Medical
5. Behavioral Science
6. … to questions of evidence of law
Timeline and History of Forensic Science
A. Early History
a. BCE – Evidence of fingerprints in early paintings and rock carvings
b. 700s – Chinese used fingerprints to establish identity
c. Ca. 1000 – Bloody palm prints
d. 1248 – Hsi Duan Yu
e. 1609 – Systematic document examination
f. 1784 – First documented use of physical matching
B. 1800s
a. First recorded use of questioned document analysis
b. The development of tests for the presence of blood in a forensic context
c. A bullet comparison used to catch a murderer
d. The first use of toxicology in a jury trial
e. The development of the first crystal test for hemoglobin
f. The development of a presumptive test for blood
g. The first use of photography for the identification of criminals and
documentation of evidence and crime scenes
h. The first recorded use of fingerprints to solve a crime
i. Development of the first microscope with a comparison bridge
C. 1900s
a. Establishment of the popular practice of using the comparison microscope
for bullet comparison in the 1920s
III.
b. Development of the absorption-inhibition ABO blood typing technique
c. Invention of the first interference contrast microscope
d. Development of the chemi-luminescent reagent luminal
e. Study of voiceprint identification
f. Invention of Breathalyzer
g. Use of heated headspace sampling technique for collecting arson evidence
h. Development of scanning electron microscope
i. Identification of polymorphic nature of red blood cells
j. Enactment of Federal Rules of Evidence
k. Evaluation of gas chromatograph and mass spectrometer
l. Development of PCR technique
m. DNA profiling test
n. DNA introduced in criminal courts
o. Daubert et al. v. Merrel Dow
p. DNA database
D. Important Individuals in the Development of Forensic Science
a. Mathieu Orfila (1787 – 1853) – considered the “father” of forensic
toxicology
b. Alphonse Bertillon (1853-1914) – Developed first system of personal
identification
c. Francis Galton (1822 – 1911) – Developed methodology for fingerprinting
d. Leone Lattes (1887-1954) – Developed techniques to ID ABO blood
groups
e. Calvin Goddard (1891-1955) – expert in ballistic analysis
f. Albert Osborn (1858-1946) document examination
g. Walter McCrone (1916-2002) – instrumental in using and perfecting
microscope use in forensic analysis
h. Hans Gross (1847-1915) – application of scientific disciplines to field of
criminal investigation
i. Edmond Locard (1877-1966) – Locard’s Exchange Principle = “The
exchange of materials between 2 objects that occurs whenever 2 objects
come into contact with one another”
Crime Labs and Their Role in Forensic Science and Criminalistics
A. At present there are about 320 crime labs in the US
B. This growth has led to the advent of DNA profiling
C. The Big 8
a. FBI – Federal Bureau of Investigation
i. Biggest in Justice Department, limited to 200 crimes, training, lab
support
b. DEA – Drug Enforcement Agency
i. Best at strategy, surveillance, joint ops
c. USMS – United States Marshall Service
i. Provide security and transport for whole system
d. INS – Immigration and Naturalization Service
i. Less detective than others, are apprehension specialists
e. ATF – Bureau of Alcohol, Tobacco and Firearms
i. Treasury counterpart to FBI, interest in growing, training, lab
support
f. IRS – Internal Revenue Service
i. Tax related, anything with underground economy
g. USCS – United States Customs Service
i. Large import/export, contraband, porno duties
h. USSS – United States Secret Service
i. Secret service, VIP protection, counterfeiting and fraud
D. Crime Labs
a. Function to train police investigators as to what constitutes physical
evidence and how it should be collected, preserved, etc.
b. Analyze this evidence
c. Basic Services
i. Physical Science Unit – chemistry, physics, and geology;
sometimes drug ID, soil and mineral analysis and examination of
trace evidence
ii. Biology Unit – DNA, blood, hairs and fibers and botanicals
iii. Firearms Unit – ballistics and tools
iv. Documents Unit – handwriting and typewriting
v. Photography Unit – document scenes and analysis
d. Optional Services
i. Toxicology
ii. Latent Fingerprints
iii. Polygraph
iv. Voiceprint Analysis
v. Evidence Collection
e. Other Services
i. Pathology – medical dissection and examination of a body in order
to determine the cause of death
1. Autopsy – performed to establish the cause and manner of
death
a. Natural
b. Homicide
c. Suicide
IV.
d. Accident
e. Undetermined
2. Stages of decomposition – time of death
a. Rigor mortis = the medical condition that occurs
after death and results in the shortening of muscle
tissue and the stiffening of body parts in the
position they are in when death occurs
b. Livor mortis – The medical condition that occurs
after death and results in the settling of blood in
areas of the body closest to the ground
c. Algor mortis – Postmortem changes that cause a
body to lose heat
ii. Anthropology – age, sex, race etc
iii. Entomology – insects
iv. Psychiatry
v. Odontology – dental records
vi. Engineering
E. Problems of Crime Labs
a. Chain of Custody – Three source of error
i. Evidence has to be discovered
ii. It has to be collected
iii. It has to be transported to the lab where it is logged in, assigned an
identification number, placed in storage, and kept from mingling
with other evidence
b. Labs must be free of contaminants
c. Tests must be performed properly and documented
d. Evidence transported back into storage
e. Reports written on analysis of evidence
F. Accreditation Process
a. Quality control manual
b. Quality assurance manual
c. Lab Testing protocol
d. Program for proficiency testing: workers up to standards
G. In general, attacks on lab expertise comes in 3 categories
a. Tampering
b. Contamination
c. Substitution (mistake)
Role of Forensic Scientist
A. Analysis of Physical Evidence
a. Must be aware of demands and constraints imposed by judicial system
b. Evidence/Science must be admissible in court
c. Frye v. US (1923)
i. Court must decide if procedure, technique or principles are
“generally accepted” by a meaningful segment of relevant
scientific community
d. Federal Rules of Evidence – more flexible standards for evidence
e. Daubert v. Merrell Dow Pharmaceutical Inc (1993)
i. Frye standard is not an absolute pre-requisite to admissibility of
evidence
ii. Guidelines
1. Can technique/theory be (been) tested
2. Has technique/theory been subject to peer review and
publication
3. Techniques potential rate of error
4. Existence and maintenance of standards
5. Has theory/method attracted acceptance within relevant
scientific community
B. Provision of Expert Testimony
a. Expert Witness = an individual whom the court determines possess
knowledge relevant to the trial that is not expected of the average
layperson
C. Furnishing Training in the Proper Recognition, Collection and Preservation of
Physical Evidence