Transcript An Introduction to Forensic Science I

An Introduction to
Forensic Science
Forensic Science I
Course Topics & Perspective
Forensic science is the application of
scientific knowledge to questions of civil
and criminal law.
This course is a lab-based, hands-on
course that will explore what forensic
scientists do. You will learn modern
forensic methods and use scientific
methods to solve legal problems.
Course Topics & Perspective
Course focus is on the collection and
analysis of crime scene evidence (such
as serology, toxicology, entomology,
odontology and trace evidence), and the
Exploration of lab analysis techniques,
(such as chromatography, DNA
analysis, fingerprinting, and hair and
footprint analysis).
Course Topics & Perspective
Forensic scientists are also required to testify
in court about their analysis of evidence.
To make a convincing case, you need to be
able to clearly and concisely explain your
results and their significance in lab reports.
Finally, mock crime scenes will be
investigated and real case studies analyzed.
Interdisciplinary Relationships
Forensics is a diverse field, and rarely are
forensic scientists “generalists” – people who
specialize in all aspects of forensic science.
Forget what you see on CSI.
Forensic scientists don’t wear pumps to a crime
scene, they rarely interview suspects or make
arrests, and they are not experts in all areas of
forensic investigations. Rather, forensic experts
usually specialize in one or two branches of
forensic investigation.
Interdisciplinary Relationships
A botanist may be an expert in forensic
botany. An entomologist may be an expert
in forensic entomology. Chemists may
specialize in forensic toxicology or arson
and bomb analysis. People with expertise
in physics may focus on firearms and
ballistics or blood spatter analysis.
Interdisciplinary Relationships
It would be impossible to survey all areas
of forensic science in a semester long high
school course.
Rather, we will explore a range of fields,
topics and methodologies to give you a
sense of the diverse fields of study in
forensics.
Interdisciplinary Relationships
Nevertheless, forensic science is an
applied scientific discipline, and your
success in this course will require you to
apply your basic understanding of physics,
chemistry, biology and even math to
explore the range of topics surveyed.
Forensic Science Defined:
Forensic Science (or Criminalistics) is the
use of science & technology to enforce
civil & criminal laws.
It is somewhat hard to pin down exactly
what a forensic scientists does because it
includes so many other areas of science.
Why do we look to science for
assistance in our legal system?
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Increasing Crime Rates
New or Changed Laws
New Crimes
New Weapons (*see next slide)
Response to Public Concerns
Response to Law Enforcement
Concerns
Basic Services Provided by
Crime Laboratories
Physical Science Unit
 Biology Unit
 Firearms Unit
 Photography Unit
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Physical Science Unit
 Chemistry (drugs,
explosives)
 Physics (glass,
scratches)
 Geology (soil, rocks)
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Biology Unit
Bloodstains
 Body fluids
 Hair and fiber
 Botanical materials (wood
and plants).
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Firearms Unit
Firearms
 Bullets
 Cartridge & Shells
 Ammunition
 Garments
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The Functions of
Forensic Scientists
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Collect and Analyze
Physical Evidence
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Demands & Constraints
When and where do we
collect?
 How do we collect?
 For what purpose?
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New Weapons?
Applying Science to Law
Applying science to the Criminal
Justice System depends on a
scientist’s ability to supply
accurate & objective information
that reflects the events that have
occurred at a crime.
Civil vs. Criminal Law
CIVIL LAW
CRIMINAL LAW
 filed by a private party.
o a corporation
o an individual
 filed by the government
 Penalty: a guilty
defendant pays the plaintiff
for losses caused by their
actions.
o no incarceration
 Penalty: a guilty defendant is
punished by
o incarceration (in jail/prison)
o fine paid to the gov’t
o execution (death penalty)
 Crimes are divided into 2
classes:
o misdemeanors - < 1 year
incarceration
o felonies - 1+ year sentence
History & Development of
Forensic Science
When in Rome…
“Forensic” comes from the Latin word
“forensis” meaning forum.
 During the time of the Romans, a criminal
charge meant presenting the case before
the public.
 Both the person accused of the crime & the
accuser would give speeches based on
their side of the story.
 The individual with the best argument
would determine the outcome of the case.

Sir Arthur Conan Doyle
 Mystery
author in late 1800’s
 Popularized
scientific crimedetection methods through his
fictional character ‘Sherlock
Holmes’.
Mathieu Orfila
(1787-1853)
 “Father
 Wrote
of Toxicology”
about the detection of
poisons & their effects on
animals.
Alphonse Bertillon
(1853-1914)


“Father of Anthropometry”
Developed a system to distinguish one
individual person from another based on
certain body measurements.
Anthropometry
Francis Galton
(1822-1911)

“Father
of Fingerprinting”
 Developed
fingerprinting as a
way to uniquely identify
individuals.
Leone Lattes
(1887-1954)

“Father of Bloodstain Identification”

He developed a procedure for
determining the blood type (A, B, AB,
or O) of a dried blood stain.
Calvin Goddard
(1891-1955)
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“Father of Ballistics”
Developed the technique to examine
bullets, using a comparison
microscope, to determine whether or
not a particular gun fired the bullets.
Albert Osborn
(1858-1946)

“Father of Document Examination”

His work led to the acceptance of
documents as scientific evidence by the
courts.
Walter McCrone
(1916-2002)
of Microscopic Forensics”

“Father

He developed & applied his
microscope techniques to examine
evidence in countless court cases.
Hans Gross
(1847-1915)


“Father
of Forensic Publications”
Wrote the book on applying all the
different science disciplines to the
field of criminal investigation.
Edmond Locard
(1877-1966)
• “Father of the Crime Lab”
• In 1910, he started the 1st crime lab in an
attic of a police station in Paris, France.
• With few tools, he quickly became known
world-wide to forensic scientists & criminal
investigators & eventually founded the
Institute of Criminalistics in France.
• His most important contribution was the
“Locard’s Exchange Principle”
Locard’s Exchange Principle
• “Every Contact Leaves a Trace.”
• He believed that every criminal can be
connected to a crime by particles carried
from the crime scene.
• When a criminal comes in contact with an
object or person, a cross-transfer of
evidence occurs.
J. Edgar Hoover

“Father of the FBI” - Director of Federal Bureau
of Investigation during the 1930’s

Hoover's leadership spanned 48 yrs & 8 presidential
administrations. His reign covered Prohibition, the Great
Depression, WWII, the Korean War, the Cold War, & the
Vietnam War.

He organized a national laboratory to offer forensic
services to all law enforcement agencies in the U.S.

VERY CONTROVERSIAL
– He exceeded & abused his authority with unjustified
investigations & illegal wiretaps based on political beliefs rather
than suspected criminal activity
– FBI directors are now limited to 10-year terms
Applications of Forensic Science
Identification of Criminals or Victims
 Solving Mysteries
 Past crimes (unsolved or wrongfully
convicted)
 Cause, Location, Time of Death
 Paternity cases
 Cyber crimes
 Corporate Crimes (Enron)
 Voice Analysis

Applications of Forensic Science
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Application of DNA as evidence
Prevention vs. Reaction
Catastrophes & Wars
 ID remains of victims (either civilian or
soldiers)
 ex. Holocaust or Katrina
Military & International Forensics
 Terrorism
 The search for WMD’s
 stockpiled or stored weapons from past wars
Munitions
When the Army unearthed more than a
1,000 mortar rounds from a WW2
training site, they enlisted a Forensic
Science Lab to determine which were
live munitions & which were dummies.
The Trial of the Century
• O.J. Simpson was a NFL football legend.
• He is now famous for having been tried for
the murder of ex-wife Nicole Brown
Simpson & her friend Ronald Goldman in
1994.
• He was acquitted in criminal court after a
lengthy, highly publicized trial.
What went wrong?
• 1st on the scene, police found evidence of blood
& entered the Simpson home without a search
warrant, an action permissible b/c the situation
was an emergency.
• HOWEVER, the police collected a pair of bloodstained gloves during their search.
• Collection of evidence without proper warrants
became the key argument used by Simpson’s
legal team & ultimately led to his acquittal.
What was learned?
• If forensic evidence is to be admissible in
court, the highest professional standards
must be used at the crime scene!
• He was found liable for their deaths in civil
court, but has yet to pay the $33.5 million
judgment.
The Wonderful Weirdness of Forensic Science:
The Body Farm
• Primary Goal: To understand the processes
& timetable of postmortem decay, primarily to
improve determining the "time since death" in
murder cases.
• The Body Farm is a simulation of various
crime scenes using real human bodies.
• Started in 1970’s by Dr Bill Bass to study
Forensic Anthropology (the study of human
decomposition after death).
The Body Farm
• Used by Law Enforcement, Medical Examiners,
Entomologists, Cadaver Dogs, Anthropologists &
FBI for Crime Scene Training.
• The BF uses unclaimed cadavers & volunteers
(who donate their body to science after death)
• Only 2 Facilities in the U.S.
– Univ. of Tennessee (original)
– Western Carolina University
Doorway to death, the main gate of the
Anthropology Research Facility—the “Body
Farm”—consists of a wooden privacy fence
inside a chain-link fence topped with razor wire.
Security is a high priority. Fences, padlocks,
video surveillance cameras, & police patrols
safeguard the world’s only humandecomposition research facility.
One research study examined the effects of
the elevated temperatures—and limited
insect access—to which a body in a car
would be subjected.
Corpse 1-81 was an elderly white male; he
became part of a pioneering study of insect
activity in human corpses.
Close-up of a recent research subject. After only a few weeks
in the Tennessee summer, the skull is completely bare &
many vertebrae are exposed. The rib cage & pelvis are
covered with dried, leathery skin, but the soft tissues
beneath are gone, consumed by insects & bacteria.
Close-up of a human femur & hip bone,
containing an artificial hip implant. Such
orthopedic devices can help identify an
unknown crime victim.
An aerial view of the Body Farm. Large wooden
tripods are used for hoisting & weighing bodies as
part of a research study of weight loss during
decomposition.
A jaw from a research subject held by the
founder of the Body Farm, Dr Bill Bass.
Key Question: Time Since Death?
How does the decomposition rate compare in:
– sunshine vs shade?
– In cool weather vs hot weather?
– In a shallow grave vs on the ground?
– In water?
– Inside a car?
– What effect do other variables have—humidity,
insect activity, clothing, body weight, & so on?
Why is TSD so important?
• 1st question at most murder scenes: "How
long has this person been dead?“
– TSD: Time Since Death
• It's crucial to know when the crime was
committed.
– it can help narrow the search for a suspect or
– it can help rule out potential suspects who
had alibis at the time the victim was killed.