Transcript FORENSIC SCIENCE

FORENSIC
SCIENCE
INTRODUCTION
UNITS
FIRST SEMESTER
Introduction
Physical Evidence
DNA
Documentation
Biology
SECOND SEMESTER
Introduction
Prints
Toxicology
Trace Evidence
Serology
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Forensic Science
Application of science to those criminal and civil laws
that are enforced by police agencies in a criminal
justice system.
The business of providing timely, accurate, and thorough
information to all levels of decisions makers in our
criminal justice system.
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CORPUS DELICTI
You must prove:
“Body of the Crime”
 that a crime occurred
 that the person charged with the crime was responsible for the crime
Top Reasons for Committing a Crime
 Money
 Revenge
 Sex
 Emotion--love, hate, anger
Source of Evidence
 Body
 Primary and/or Secondary Crime Scene
 Suspect(s)
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FACETS OF GUILT
Means--the ability of have committed the crime
Motive--the reason for committing the crime.
(This doesn’t have to be proven or presented in
a court of law, but its what everyone wants to
know.)
Opportunity--time or availability to have
committed the crime.
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Murder Charges
1st Degree Murder--premeditated
2nd Degree Murder--killed intentionally, but
not thought out as much ahead of time
Voluntary Manslaughter--usually involves
sudden passion (fear, rage, anger, terror)
Involuntary Manslaughter (criminally negligent
homicide)--killed someone, but unintentionally
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Evidence
Characteristics
Class--common to a group of objects or persons
Individual--can be identified with a particular person or
source.
ABO Blood Typing
Blood DNA Typing
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Crime Scene Team
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First Officer
ADAPT
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Medical Examiner’s
Officer sent to the scene
 Livor mortis
 Rigor mortis
 Algor mortis
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Medical Examiner’s
Responsibilities
 Identify the deceased
 Establish the time and date of death
 Determine a medical cause of death--the injury or disease that resulted in the person
dying
 Determine the mechanism of death--the physiological reason that the person died
 Classify the manner of death





Natural
Accidental
Suicide
Homicide
Undetermined
 Notify the next of kin
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Crime Scene
Sketch
Date: August 14, 2001
Time: 11:35
Criminalist: Ann Wilson
Location: 4358 Rockledge Dr
St. Louis, Mo.
A. Couch/sofa
E
c
B. Female body
D
C. Knife
D. Over turned Lamp
E. Chairs
E
F. Table
G. Fireplace
G
A
F
E
E
E
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Complex Reasoning
In Forensic Science
Deductive and Inductive
Reasoning
Classifying
Comparing and contrasting
Problem Solving
Analyzing Perspectives
Constructing Support
Error Analysis
Logic
 Logic: A system of
reasoning that leads to
inferences
 Inference: drawing
conclusions based on known
facts, collection of data and
the relationships between that
data
 Conclusion
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EYEWITNESS
Crazy Criminal
Suspect Falters
Over Account of Robberies
Robbery suspect Frank Margary can’t seem
to keep his mouth shut. In some subtle
statements, he has confessed to a series of
robberies. When questioned about a
November robbery at Lakeside Deli and
Mini Market, he told detectives: “There’s
no way the clerk could identify me, I had
my hat down over my eyes.”
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Remember:
“HOW PLUS WHY EQUALS WHO”
--John Douglas, former FBI profiler
Keep this in mind as you set up your crime scene
and work up your lab.
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History-Repeating Itself?
1840
1860
1880
1900
1920
1940
1960
1980
2000
William Henry Harrison--died in office
Abraham Lincoln--assassinated
James A. Garfield--assassinated
William McKinley--assassinated
Warren G. Harding--died in office
Franklin D. Roosevelt--died in office
John F. Kennedy--assassinated
Ronald Reagan--survived assassination attempt
George Bush--KIND OF SCARY?
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Evidence Technician
 Will set up numbers at the 10
pieces of evidence
 One piece of evidence must
come from each of the units in
this semester.
 Will help the other team
collect evidence
 Have the necessary equipment
 Forceps
 Bags--paper and plastic
 Envelopes
 Jars and Q-tips
 Properly collect all evidence
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