Title: DO NOW Sept 5
1DO NOW Sept 5
- An officer responds to a disturbance in a parking
lot where he finds a young man has suffered a
gunshot wound to the lower torso. The weather is
cold and raining. The officer checks that the
victim is breathing and begins to seal off the
crime scene. The officer immediately checks the
scene for any signs of evidence. He then calls in
for officer assistance and an ambulance. - Evaluate the actions of the officer.
2DO NOW Answer
- The officer does not follow the proper protocol
in this situation. - The officers actions may have been dictated by
the fact that it was raining outside and that any
possible evidence may have been washed away or
destroyed. - However, first priority is always the safety and
welfare of any victims on scene.
3FORENSICSChapter 1 Introduction to Forensic
Science
4Why do we need laws in our society?
- What do laws regulate in our society?
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5Introduction
- Laws are a necessity to regulate
- The quality of our food
- The potency of drugs
- The quality of water
- The preservation of nature
- The honesty and integrity of mankind.
- Ensure the safety and security of law-abiding
citizens against criminal acts.
6What is Forensics?
- The application of science to criminal and civil
law that are enforced by police agencies in a
criminal justice system. - Forensic science owes its origins to individuals
who developed the principles and techniques
needed to identify and compare physical evidence.
7Elementary, my dear Watson
- Popular media has marginalized and
sensationalized the importance of the scientific
process behind forensic science.
8History
- Mathieu Orfila the father of forensic
toxicology. - Alphonse Bertillion - devised the first
scientific system of personal identification in
1879. - Francis Galton conducted the first definitive
study of fingerprints and their classification. - Leone Lattes developed a procedure to determine
blood type from dried blood stains.
9Blood Typing
- Which blood type is the universal donor?
- Which blood type is the unviversal recipient?
- (Here is a little bit of Biology!)
10DO NOW Sept 9
- A blood sample taken from a crime scene is type
A. Police arrest a suspect with type A blood but
claims he did not commit the crime. He tells
police that his half brother is guilty of the
crime. Both men have the same mother whose blood
type is B. - If the father of the half brother has type O
blood, was the blood sample left by the half
brother?
11DO NOW ANSWER
- No, the half brother can only have blood type B
or O. - The half brother did not leave his blood at the
crime scene. - Solve Punnett Squares!
12Blood Types
O is most common blood type.
O is the universal donor. AB is the universal
recipient.
13History
- Walter McCrone utilized microscopy and other
analytical methodologies to examine evidence. - Hans Gross wrote the first treatise describing
the application of scientific principles to the
field of criminal investigation. - Edmond Locard incorporated Gross principles
within a workable crime laboratory. - Locards Exchange Principle states that a
cross-transfer of evidence occurs when a criminal
comes in contact with an object or person.
14The Crime Lab
- Rapid growth
- Lack of national and regional planning and
coordination. - Paul Leland Kirk (1902-1970) was head of first
criminalistics department at the University of
California Berkeley. - 350 public crime labs operating at four levels of
government - federal, state, county, and municipal.
15Is Forensic Science Infallible?
- http//www.nytimes.com/2014/05/19/us/dna-analysis-
exposes-an-inexact-forensic-science.html
16AGENDA Monday Sept 15
- Learning Objective Describe the technical
services available to analyze evidence. - 1. Crime Team Poster Grades
- 2. Technical Services
- 3. Finish Anthropometry LAB Part 1
- 4. Introduce PART 2
- 5. Homework and Review
17Why did Crime Labs begin to expand in size and
number?
- Factors that affected Crime Labs
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18The Crime Lab
- Increasing numbers of crime labs partly on the
rise due to - Supreme Court decisions in the 1960s
- police to build cases on scientifically evaluated
evidence. - High levels of drug abuse
- crime labs unable to keep up with demands.
- DNA profiling technology
19Technical Support
- Five basic services.
- Physical Science Unit use of chemistry,
physics, and geology to identify and compare
physical evidence. - Biology Unit use of biology to investigate
blood samples, body fluids, hair, and fiber
samples. - Firearms Unit investigates discharged bullets,
cartridge cases, shotgun shells, and ammunition.
20Technical Support
- Document Unit analyzes handwriting and
questioned-document issues. - Photographic Unit applies specialized
photographic techniques for examining and
recording physical evidence.
21Optional Tech Services
- Toxicology Unit examines body fluids and organs
for the presence of drugs and poisons. - Latent Fingerprint Unit
- Polygraph Unit
- Voiceprint Analysis Unit analyze voice patterns.
- Evidence Collection Unit specially trained
individuals collect and preserve physical
evidence.
22Skills of a Forensic Scientist
- Apply principles and techniques of physical and
natural sciences. - Analyze various types of evidence.
- Provide expert court testimony.
23Skills of a Forensic Scientist
- Expert witness determined by the court to
possess knowledge relevant to a trial that is not
expected of the average person. - Evaluates evidence based on training and
experience that the court lacks the expertise to
do. - Provides an expert opinion as to the significance
of findings. - Assist in the training of law enforcement in the
proper recognition, collection, and preservation
of physical evidence.
24Forensics at Work
- http//www.abc.net.au/btn/story/s3527744.htm
25FRYE vs. the United States 1923
- Defendant was convicted of Second Degree Murder.
- An early form of a Polygraph test was used by
prosecution as key evidence in the case. - Systolic Blood Pressure Deception Test
26- Scientific experiments have demonstrated that
fear, rage, and pain always produce a rise of
systolic blood pressure. - Conscious deception or falsehood, concealment of
facts, or guilt of crime, accompanied by fear of
detection. - Indicates the struggle going on in the subject's
mind between fear and attempted control of that
fear under examination.
27THE RULING
- Expert testimony deduced from a well-recognized
scientific principle or discovery. - Deduction made must be sufficiently established
to have gained general acceptance in the
particular field in which it belongs.
28The Frye Standard
- The Frye v. the United States decision set the
guidelines for determining admissibility of
scientific evidence into the courtroom. - To meet the Frye Standard, evidence in question
must be generally accepted by the scientific
community.
29Frye Not Absolute
- 1993 case of Daubert v. Merrell Dow
Pharmaceutical, Inc. - U.S. Supreme Court asserted that Frye Standard is
not an absolute prerequisite to the admissibility
of scientific evidence. - Trial judges are ultimately responsible as
gatekeepers for the admissibility and validity
of scientific evidence presented in their courts
as well as expert testimony.
30The Daubert Criteria
- In Daubert, Supreme Court offered guidelines as
to how a judge can gauge scientific evidence. - 1. Whether the scientific technique or theory can
be (and has been) tested. - 2. Whether the technique or theory has been
subject to peer review and publication. - 3. The techniques potential rate of error.
- 4. Existence and maintenance of standards
controlling the techniques operation. - 5. Widespread acceptance of scientific theory or
method within a relevant scientific community.
31Unsolved Crimes
- http//www.youtube.com/watch?vs27fxRk9dpE
- Get into your CRIME TEAMS!
- ELECT A SPOKESPERSON!
32Unsolved Crimes
- Based upon what you have seen, what steps may
have been taken to further investigate these
murders? - Do you believe both crimes were committed by the
same individual/individuals? WHY? - Write your answers on a piece of paper.
33UNSOLVED CRIMES
- Physical evidence on the victims.
- ID the type of instrument that caused the
injuries to the victims. - Cross reference the DNA found on the cigarettes.
- Good old fashioned police work walk the beat
and ask questions. - Retrace the path of the victims.
- Search surrounding area/waters for a weapon.
- Attempt to ID a possible means/route of escape
for the attackers (search the local parking lots,
etc)
34Investigation Sept 23
- What the following video clip?
- Pay close attention to the piece of evidence in
question. - http//www.youtube.com/watch?vzVrUbkHJuHY
35Special Forensic Services
- Forensic Pathology involves the investigation of
unnatural, unexplained, or violent deaths. - Medical examiners or coronersdetermine the cause
of death. - Autopsy or medical dissection and examination of
a body.
36Stages of Death
- RIGOR mortis results in the shortening of
- muscle tissue and stiffening of body parts
- in the position at death.
- Occurs within first 24 hours and disappears
within 36 hours. - LIVOR mortis results in the settling of blood in
areas of body closest to the ground. - Begins immediately on death up to 12 hours
after death.
37Special Forensic Services
- ALGOR mortis results in loss of body heat.
- General rule begins an hour after death.
- Body loses heat at a rate of 1 to 1.5
degrees F per hour until body reaches
environmental temperature.
38Stages of Death
39Special Forensic Services
- Forensic Entomology is the study of insects and
their relation to a criminal investigation often
to estimate time of death. - Forensic Psychiatry involves the relationship
between human behavior and legal proceedings. - Forensic Odontology involves the use of teeth and
bite marks to assist in identifying a victim in
an unrecognizable state.
40Special Forensic Services
- Forensic Engineering involves failure analysis,
accident reconstruction, and the causes and
origins of fires and explosions. - Forensic Computer Science involves the
examination of digital evidence.