Download NOTES ch. 1 Intro. to Forensics

Chapter 1 – Introduction
Forensic Science – application of science to criminal and civil laws that are enforced by
police agencies in a criminal justice system.
What are some of the problems of the CSI effect?
History of Forensic Science – Techniques needed identify and compare physical
evidence and merge these principles to apply to the criminal justice system.
China in the third century: Was the man alive or dead when burned? How did the
coroner know?
What other forensic identification tool did the Chinese recognize?
1775 – Swedish chemist Carl Wilhelm Scheele devised the first successful test for
arsenic in corpses.
1814 – Mathieu Orfila “father of forensic toxicology” – Published first scientific treatise
on detection of poisons and their effects on animals.
1860s - photography used to record crime scenes
Morphology - study of the structure of living organisms
Bertillon (French) – father of criminal identification

Anthropometry – taking a series of body measurements to be used to
accurately identify individuals.
1900s - fingerprinting replaced anthropometry as more accurate.
1892 Francis Henry Galton (English) published Finger Prints – contained statistical
proof supporting uniqueness of using fingerprints for personal identification.
1893 Hans Gross (Austrian) published Criminal Investigation showing how fields of
microscopy, chemistry, physics, mineralogy, zoology, botany, etc can be used for
criminal investigations.
Serology – study of blood and bodily fluids
1901 – blood typing into A, B, AB and O
1910 - Albert Osborn – fundamental principles of document examination
1910 – Edmond Locard (French) developed the first criminal scientific laboratory in
Lyons, France

Locard’s exchange principle – when 2 objects come into contact with one
another, there is exchange of materials between them.

Locard believed that every criminal could be connected to a crime by dust
particles carried from the crime scene.
Dr. Walter C. McCrone – used microscopic techniques for forensic science
1984 - Sir Alec Jeffreys – DNA profiling – powerful tool to determine the precise identity
of a suspect.
Modern advancements in forensic science:
a. DNA profiling
b. computerized databases – such as fingerprints, DNA and bullet casings
able to compare evidence from thousands of pieces of crime scenes
Crime Laboratories
1923 – oldest forensic laboratory in Los Angeles, CA.
1932 – the FBI organized the first national laboratory which offered services to all law
enforcement agencies in the country. Now the world’s largest forensic laboratory.
1981 – opening of FBI’s Forensic Science Research and Training Center
No national system of laboratories, instead local law enforcement agencies operate
their own independent labs.
Reasons for growth of crime labs:
a. greater police emphasis on scientific evidence
b. requirement to advise suspects of their constitutional rights – eliminated
confessions
c. increase in crime rates
d. DNA profiling availability
Only a small percentage of police investigations require the use of a crime laboratory.
The exception is in drug-related cases which require chemical analysis of all drugs
seized.
Crime labs have a substantial backlog of DNA samples to analyze.
CODIS – Combined DNA Index System
California is collecting DNA samples from all people arrested on suspicion of a felony,
even if not convicted.
Department of Justice:
a. FBI – largest crime lab in the world
b. DEA – analyze drugs
c. Bureau of Alcohol, Tobacco, Firearms, and Explosives (ATF) – analyze
alcoholic beverages, documents, weapons, explosives
d. US Postal Inspection Service – criminal investigation related to the postal
service
Services of the Crime Laboratory:
a. Physical Sciences unit: techniques of chemistry, physics, and geology to
crime-scene evidence
b. Biology unit: DNA profiling, compare hair fibers and plant material
c. Firearms unit: examines firearms, discharged bullets, shells, ammunition.
d. Document examination unit: handwriting and typewriting on questioned
documents, analyzing paper and ink and indented writings (depressions
under another sheet), erasures, burned or charred documents.
e. Photography unit: digital images, infrared, ultraviolet, and Xray photography.
f. Toxicology unit: examines body fluids and organs to determine presence of
drugs and poisons
g. Latent fingerprint unit: processes and examines evidence for latent
fingerprints (latent = not visible)
h. Polygraph unit: handled by people trained in its techniques
i. Voiceprint analysis unit: deals with cases involving telephoned threats or
tape-recorded messages. Uses a sound spectrograph creating a graphic
display called a voiceprint.
j. Crime scene investigation unit: dispatches specially trained personnel to a
crime scene to collect and preserve physical evidence.
Forensic psychiatry – examines relationship between human behavior and legal
proceedings and examine a suspect’s behavioral profile.
Forensic odontology – help identify victims bases on dental evidence. Teeth are made
of enamal, the hardest substance in the body, so teeth remain after tissues and organs
have decomposed. Bite mark analysis to compare bite marks on a victim to the tooth
structure of a suspect.
Forensic engineering – failure analysis, accident reconstruction, and causes and origins
of fires and explosions.
Forensic computer and digital analysis – identifying, collecting, preserving, and
examining information derived from computers and other digital devices. Recovering
deleted data, tracking hacking activities, etc.
Functions of the Forensic Scientist:
Three major ways for investigators to solve crimes:
1. confessions
2. eyewitness accounts – faulty memories, lapses in judgment
3. physical evidence from the crime scene – only one free of inherent error or
bias
Scientific Method:
Ensures careful and systematic collection, organization, and analysis of
information. Ensures the outcome is not tainted by human emotion.
1923 – Frye v. United States – ruled that in order for evidence to be admitted in court it
must be “generally accepted” by a meaningful segment of the relevant scientific
community.
In 1993 Daubert v. Merrell Dow Pharmaceuticals, Inc. the U.S. Supreme Court ruled
that the Frye standard (general acceptance) is not an absolute prerequisite to the
admissibility of scientific evidence. Under the Federal Rules of Evidence (esp. Rule 702)
expert testimony can be admissible if: a) based on sufficient facts and data, b) product
of reliable principles and methods, and c) the witness has applied principles and
methods reliably to the facts of the case.
The trial judge is to be the “gatekeeper” in the courtroom to ensure the evidence
presented rests on sound scientific principles.
Expert witness – an individual whom the court determines to possess knowledge
relevant to the trial that is not expected of the average layperson.
Evidence technicians – trained to recognize and gather pertinent physical evidence at
the crime scene.