Transcript IRP 4 Forensics

IRP 4 Forensics
Introduction to Forensics
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What is forensics?
• Aka. Criminalistics
• It is the application of science to those
criminal and civil laws that are enforced by
police agencies in a criminal justice system
• In short: application of science to law
• Comes from the latin word “forum” meaning
“public”
• Includes chemistry, biology, physics, and
geology
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Job of a Forensic Scientist
• Minimum 4 year degree (the norm is a
Masters degree) in the field of forensics
• Specialize in one or two fields only
• Main jobs is to:
analyze evidence
testify in court
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How did forensics start?
• Sir Arthur Conan Doyle
- author of Sherlock Holmes
- credited with making scientific crimedetection methods popular (1st book in
1887)
- his character applied fingerprinting,
firearm identification and questioned
document examination long before
their value was first recognized
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Sir Arthur Conan Doyle
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How did forensics
continue?
• Mathieu Orfila (1787-1853)
- father of forensic toxicology
- published book on the detection of
poisons and their effect on animals
- became famous after determining the
death of a husband was caused by the
wife’s repeated doses of poison in her
husband’s food
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How did forensics
continue?
• Alphonse Betrillon (1853-1914)
-first scientific system to personal
identification
- developed science of anthropometry
(systematic procedure of taking a series of
body measurements as a means of
distinguishing one individual from another)
- considered valid for nearly two decades
- replaced by fingerprinting… WHY?
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How did forensics
continue?
• Francis Galton (1822-1911)
-1st study of fingerprints and a
methodology of classifying them for
filing
- 1st published book on fingerprints
proving their uniqueness and use for
identification; stole these findings from
others
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How did forensics
continue?
• Leon Lattes (1887-1954)
- used Karl Landsteiner’s discovery of blood
types as a useful technique for identifying
individuals
- developed a procedure for determining the
blood group of a dried bloodstain
- was immediately applied to criminal
investigations
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How did forensics
continue?
• Calvin Goddard (1891-1955)
- put the microscope to use in
determining if a particular firearm shot a
bullet
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How did forensics
continue?
• Albert S. Osborn (1858-1946)
- document examination
- became scientific evidence in court
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How did forensics
continue?
• Edmond Locard (1877-1966)
- founder of the Institute of
Criminalistics at the University of Lyons
(France)
- believed when a criminal came in
contact with an object or person, a
cross-transfer of evidence occurred
- this became known as Locard’s
Exchange Principle
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Forensics and the U.S.
• Most ambitious to adopt this emerging
science
• 1932, FBI organized a national lab that
would offer forensic services to all law
enforcement in the country
• Today, the FBI’s lab is the largest
forensic lab in the world; ~1 million
examinations each year
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Forensics and the U.S.
• Oldest forensic lab in U.S. is the Los Angeles
Police Departments (1923)
• This lab was created by August Vollmer who
later headed the first institute of criminology
at the University of California at Berkeley
• School lacked fame until 1948 when it
became active at creating labs nationwide
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Public vs. Private Labs
• Public Labs
- only accessible by judicial personnel and
police
- overloaded
- some 470+ in the country
• Private Labs
- more expensive
- available to the public
- only 50-100 in the country
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Basic Services of a Crime
Lab
• Physical Science Unit
- use chemistry, physics, and geology
for the identification and comparison of
crime-scene evidence
ex. Drugs, glass, paint, explosives, and
soils
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Basic Services of a Crime
Lab
• Biology Unit
- biologists and biochemists
- identify DNA, dried blood stains, and
other body fluids
- the comparison of hairs/fibers
- botanical materials such as wood and
plants
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Basic Services of a Crime
Lab
• Firearm Unit
- examine firearms, discharged bullets,
cartridge cases, shotgun shells, and
ammunition of all types
- garments tested for discharge
residues and to approximate the
distance from a target at which a
weapon was fired
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Basic Services of a Crime
Lab
• Document Examination Unit
- handwriting and typewriting on
questioned documents are studied
- ascertain the authenticity/source
- paper and ink analysis as well as
examination of indented writings,
obliterations, erasures, and burned or
charred documents
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Basic Services of a Crime
Lab
• Photography Unit
- examine and record physical evidence
- techniques include digital imaging,
infrared, ultraviolet, and X-ray
photography
- also aid in photo exhibits used in court
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Optional Crime Services
• Toxicology: body fluids and organs
tested for presence/absence of drugs
and poisons
• Latent Fingerprint Unit: examine
prints
• Polygraph Unit: polygraph/lie detector;
sometimes in forensics lab but now
more in police agencies
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Optional Crime Services
• Voiceprint Analysis Unit: telephoned
threats or tape-recorded messages
examined; tie particular voice to a
particular suspect; use a sound
spectrograph (transforms speech into a
visual graphic display called a
voiceprint)
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Optional Crime Services
• Evidence-Collection Unit: sent to
crime scene to collect and preserve
physical evidence that will later be
processed at the crime laboratory
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Types of Forensics
• Forensic Pathology: investigation of
sudden, unnatural, unexplained or
violent deaths; typically medical
examiners or coroners
- ask “Who is the victim? Injuries
present? When did the injuries occur?
Why and how produced?” Autopsy done
if can’t tell cause of death visually
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Types of forensics
• Forensic Anthropology: identification and
examination of human skeletal remains;
bones can reveal origin, sex, approximate
age, race, and skeletal injury
• Forensic engineering: responsible for
failure analysis, accident reconstruction, and
causes of fires and explosions; mechanical
objects examined, determined if parties
involved are responsible; photos reviewed
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Types of Forensics
• Forensic Entomology: study of
insects and their relation to a crime;
used to estimate the time of death when
the circumstances surrounding crime
are unknown; after decomposition,
flies/insects are first to infest the body;
can determine death time by
development of fly larva
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Types of Forensics
• Forensic Psychiatry: specialized area
in which relationships between human
behavior and legal proceedings is
examined; determined if people are
competent to make decisions about
preparing wills, settling property or
refusing medical treatment; competent
to stand trial
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Types of Forensics
• Forensic Odontology: provide info
about the identification of victims when
the body is left in an unrecognizable
state; examine teeth, their alignment,
smiles, and bite mark analysis
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