DO NOW Sept 5 DO NOW Sept 5 An officer responds to a disturbance in a An officer responds to a disturbance in a parking lot where he finds a young man has parking lot where he finds a young man has suffered a gunshot wound to the lower suffered a gunshot wound to the lower torso. The weather is cold and raining. The torso. The weather is cold and raining. The officer checks that the victim is breathing officer checks that the victim is breathing and begins to seal off the crime scene. The and begins to seal off the crime scene. The officer immediately checks the scene for officer immediately checks the scene for any signs of evidence. He then calls in for any signs of evidence. He then calls in for officer assistance and an ambulance. officer assistance and an ambulance. Evaluate the actions of the officer. Evaluate the actions of the officer.
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DO 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.
FORENSICS Chapter 1: Introduction to Forensic Science
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DO NOW Sept 5DO NOW Sept 5 An officer responds to a disturbance in a An officer responds to a disturbance in a
parking lot where he finds a young man has parking lot where he finds a young man has suffered a gunshot wound to the lower torso. suffered a gunshot wound to the lower torso. The weather is cold and raining. The officer The weather is cold and raining. The officer checks that the victim is breathing and begins checks that the victim is breathing and begins to seal off the crime scene. The officer to seal off the crime scene. The officer immediately checks the scene for any signs of immediately checks the scene for any signs of evidence. He then calls in for officer assistance evidence. He then calls in for officer assistance and an ambulance.and an ambulance.
Evaluate the actions of the officer.Evaluate the actions of the officer.
DO NOW Answer DO NOW Answer The officer does not follow the proper The officer does not follow the proper
protocol in this situation.protocol in this situation. The officer’s actions may have been The officer’s actions may have been
dictated by the fact that it was raining dictated by the fact that it was raining outside and that any possible evidence outside and that any possible evidence may have been washed away or may have been washed away or destroyed.destroyed.
However, any injured person takes However, any injured person takes priority over the collection of evidence.priority over the collection of evidence.
FORENSICSFORENSICSChapter 1: Chapter 1:
Introduction to Introduction to Forensic ScienceForensic Science
Why do we need laws in our Why do we need laws in our society?society?
What do laws regulate in our society?What do laws regulate in our society?
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Introduction Introduction Laws are a necessity to regulate…Laws are a necessity to regulate… The quality of our foodThe quality of our food The potency of drugsThe potency of drugs The quality of water The quality of water The preservation of nature The preservation of nature The honesty and integrity of mankind.The honesty and integrity of mankind. Ensure the safety and security of law-Ensure the safety and security of law-
abiding citizens against criminal acts.abiding citizens against criminal acts.
What is Forensics?What is Forensics? The application of science to criminal and The application of science to criminal and
civil law that are enforced by police civil law that are enforced by police agencies in a criminal justice system.agencies in a criminal justice system.
Forensic science owes its origins to Forensic science owes its origins to individuals who developed the principles individuals who developed the principles and techniques needed to identify and and techniques needed to identify and compare physical evidence.compare physical evidence.
““Elementary, my dear Elementary, my dear Watson”Watson”
– Popular media Popular media has marginalized has marginalized and and sensationalized sensationalized the importance the importance of the scientific of the scientific process behind process behind forensic science.forensic science.
HistoryHistory Mathieu Orfila – the father of forensic Mathieu Orfila – the father of forensic
toxicology.toxicology.
Alphonse Bertillion - devised the first scientific Alphonse Bertillion - devised the first scientific system of personal identification in 1879.system of personal identification in 1879.
Francis Galton – conducted the first definitive Francis Galton – conducted the first definitive study of fingerprints and their classification.study of fingerprints and their classification.
Leone Lattes – developed a procedure to Leone Lattes – developed a procedure to determine blood type from dried blood stains.determine blood type from dried blood stains.
Blood TypingBlood Typing Which blood type is the universal donor?Which blood type is the universal donor?
Which blood type is the unviversal Which blood type is the unviversal recipient?recipient?
(Here is a little bit of Biology!)(Here is a little bit of Biology!)
DO NOW Sept 9DO NOW Sept 9 A blood sample taken from a crime A blood sample taken from a crime
scene is type A. Police arrest a suspect scene is type A. Police arrest a suspect with type A blood but claims he did not with type A blood but claims he did not commit the crime. He tells police that commit the crime. He tells police that his half brother is guilty of the crime. his half brother is guilty of the crime. Both men have the same mother Both men have the same mother whose blood type is B. whose blood type is B.
If the father of the half brother has type If the father of the half brother has type O blood, was the blood sample left by O blood, was the blood sample left by the half brother?the half brother?
DO NOW ANSWERDO NOW ANSWER No, the half brother can only have No, the half brother can only have
blood type B or O.blood type B or O.
The half brother did not leave his The half brother did not leave his blood at the crime scene.blood at the crime scene.
Solve Punnett Squares!Solve Punnett Squares!
Blood TypesBlood TypesO+ is most common blood type.
O is the universal donor.AB is the universal recipient.
HistoryHistory Walter McCrone – utilized microscopy and other Walter McCrone – utilized microscopy and other
analytical methodologies to examine evidence.analytical methodologies to examine evidence.
Hans Gross – wrote the first treatise describing Hans Gross – wrote the first treatise describing the application of scientific principles to the field the application of scientific principles to the field of criminal investigation.of criminal investigation.
Edmond Locard – incorporated Gross’ principles Edmond Locard – incorporated Gross’ principles within a workable crime laboratory.within a workable crime laboratory.
Locard’s Exchange Principle – states that a cross-Locard’s Exchange Principle – states that a cross-transfer of evidence occurs when a criminal transfer of evidence occurs when a criminal comes in contact with an object or person.comes in contact with an object or person.
The Crime LabThe Crime Lab Rapid growth Rapid growth Lack of national and regional planning Lack of national and regional planning
and coordination.and coordination.
Paul Leland Kirk (1902-1970) was head Paul Leland Kirk (1902-1970) was head of first criminalistics department at the of first criminalistics department at the University of California Berkeley.University of California Berkeley.
350 public crime labs operating at four 350 public crime labs operating at four levels of government levels of government
– – federal, state, county, and municipal.federal, state, county, and municipal.
Is Forensic Science Is Forensic Science Infallible?Infallible?
Learning Objective: Describe the Learning Objective: Describe the technical services available to technical services available to analyze evidence.analyze evidence.
1. Crime Team Poster Grades 1. Crime Team Poster Grades 2. Technical Services2. Technical Services 3. Finish Anthropometry LAB – Part 13. Finish Anthropometry LAB – Part 1 4. Introduce PART 24. Introduce PART 2 5. Homework and Review5. Homework and Review
Why did Crime Labs begin Why did Crime Labs begin to expand in size and to expand in size and
number?number? Factors that affected Crime LabsFactors that affected Crime Labs
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The Crime LabThe Crime Lab Increasing numbers of crime labs Increasing numbers of crime labs
partly on the rise due to…partly on the rise due to…
– Supreme Court decisions in the 1960s Supreme Court decisions in the 1960s police to build cases on scientifically police to build cases on scientifically
evaluated evidence.evaluated evidence.
– High levels of drug abuse High levels of drug abuse crime labs unable to keep up with demands.crime labs unable to keep up with demands.
– DNA profiling technologyDNA profiling technology
Technical SupportTechnical Support Five basic services.Five basic services.
Physical Science Unit – use of chemistry, Physical Science Unit – use of chemistry, physics, and geology to identify and compare physics, and geology to identify and compare physical evidence.physical evidence.
Biology Unit – use of biology to investigate blood Biology Unit – use of biology to investigate blood samples, body fluids, hair, and fiber samples.samples, body fluids, hair, and fiber samples.
Firearms Unit investigates discharged bullets, Firearms Unit investigates discharged bullets, cartridge cases, shotgun shells, and cartridge cases, shotgun shells, and ammunition.ammunition.
Technical SupportTechnical Support Document Unit analyzes handwriting Document Unit analyzes handwriting
and questioned-document issues.and questioned-document issues.
Photographic Unit applies specialized Photographic Unit applies specialized photographic techniques for photographic techniques for examining and recording physical examining and recording physical evidence.evidence.
Optional Tech ServicesOptional Tech Services Toxicology Unit examines body fluids and Toxicology Unit examines body fluids and
organs for the presence of drugs and poisons.organs for the presence of drugs and poisons.
Latent Fingerprint Unit Latent Fingerprint Unit
Polygraph Unit Polygraph Unit
Voiceprint Analysis Unit analyze voice patterns.Voiceprint Analysis Unit analyze voice patterns.
Evidence Collection Unit specially trained Evidence Collection Unit specially trained individuals collect and preserve physical individuals collect and preserve physical evidence.evidence.
Skills of a Forensic ScientistSkills of a Forensic Scientist Apply principles and techniques of physical Apply principles and techniques of physical
and natural sciences.and natural sciences.
Analyze various types of evidence.Analyze various types of evidence.
Provide expert court testimony.Provide expert court testimony.
Skills of a Forensic ScientistSkills of a Forensic Scientist Expert witness – determined by the court to Expert witness – determined by the court to
possess knowledge relevant to a trial that is possess knowledge relevant to a trial that is not expected of the average person.not expected of the average person.
Evaluates evidence based on training and Evaluates evidence based on training and experience that the court lacks the expertise to do.experience that the court lacks the expertise to do.
Provides an expert opinion as to the significance of Provides an expert opinion as to the significance of findings.findings.
Assist in the training of law enforcement in the Assist in the training of law enforcement in the proper recognition, collection, and preservation of proper recognition, collection, and preservation of physical evidence.physical evidence.
Forensics at WorkForensics at Work http://www.abc.net.au/btn/story/s352
FRYE vs. the United FRYE vs. the United States 1923States 1923
Defendant was convicted of Second Defendant was convicted of Second Degree Murder.Degree Murder.
An early form of a Polygraph test was An early form of a Polygraph test was used by prosecution as key evidence in used by prosecution as key evidence in the case.the case.
Systolic Blood Pressure Deception TestSystolic Blood Pressure Deception Test
Scientific experiments have demonstrated that Scientific experiments have demonstrated that fear, rage, and pain always produce a rise of fear, rage, and pain always produce a rise of systolic blood pressure.systolic blood pressure.
Conscious deception or falsehood, concealment of Conscious deception or falsehood, concealment of facts, or guilt of crime, accompanied by fear of facts, or guilt of crime, accompanied by fear of detection.detection.
Indicates the struggle going on in the subject's Indicates the struggle going on in the subject's mind between fear and attempted control of that mind between fear and attempted control of that fear under examination.fear under examination.
THE RULINGTHE RULING Expert testimony deduced from a well-Expert testimony deduced from a well-
recognized scientific principle or recognized scientific principle or discovery.discovery.
Deduction made must be sufficiently Deduction made must be sufficiently established to have gained general established to have gained general acceptance in the particular field in which acceptance in the particular field in which it belongs.it belongs.
The The Frye Frye StandardStandard The Frye v. the United The Frye v. the United
States decision set the States decision set the guidelines for guidelines for determining admissibility determining admissibility of scientific evidence into of scientific evidence into the courtroom.the courtroom.
To meet the Frye To meet the Frye Standard, evidence in Standard, evidence in question must be question must be “generally accepted” by “generally accepted” by the scientific community.the scientific community.
Frye Frye Not AbsoluteNot Absolute1993 case of 1993 case of Daubert v. Merrell Dow Daubert v. Merrell Dow
Pharmaceutical, Inc.Pharmaceutical, Inc.U.S. Supreme Court asserted that U.S. Supreme Court asserted that Frye Frye
Standard is not an absolute prerequisite Standard is not an absolute prerequisite to the admissibility of scientific evidence.to the admissibility of scientific evidence.
Trial judges are ultimately responsible as Trial judges are ultimately responsible as “gatekeepers” for the admissibility and “gatekeepers” for the admissibility and validity of scientific evidence presented validity of scientific evidence presented in their courts as well as expert in their courts as well as expert testimony.testimony.
TheThe DaubertDaubert CriteriaCriteria In In DaubertDaubert, Supreme Court offered guidelines , Supreme Court offered guidelines
as to how a judge can gauge scientific evidence.as to how a judge can gauge scientific evidence. 1. Whether the scientific technique or theory 1. Whether the scientific technique or theory
can be (and has been) tested.can be (and has been) tested. 2. Whether the technique or theory has been 2. Whether the technique or theory has been
subject to peer review and publication.subject to peer review and publication. 3. The technique’s potential rate of error.3. The technique’s potential rate of error. 4. Existence and maintenance of standards 4. Existence and maintenance of standards
controlling the technique’s operation.controlling the technique’s operation. 5. Widespread acceptance of scientific theory or 5. Widespread acceptance of scientific theory or
method within a relevant scientific community.method within a relevant scientific community.
Unsolved Crimes Unsolved Crimes Based upon what you have seen, what Based upon what you have seen, what
steps may have been taken to further steps may have been taken to further investigate these murders?investigate these murders?
Do you believe both crimes were Do you believe both crimes were committed by the same committed by the same individual/individuals? WHY?individual/individuals? WHY?
Write your answers on a piece of paper.Write your answers on a piece of paper.
UNSOLVED CRIMESUNSOLVED CRIMES Physical evidence on the victims.Physical evidence on the victims. ID the type of instrument that caused the injuries ID the type of instrument that caused the injuries
to the victims.to the victims. Cross reference the DNA found on the cigarettes.Cross reference the DNA found on the cigarettes. Good old fashioned police work – walk the beat Good old fashioned police work – walk the beat
and ask questions.and ask questions. Retrace the path of the victims.Retrace the path of the victims. Search surrounding area/waters for a weapon.Search surrounding area/waters for a weapon. Attempt to ID a possible means/route of escape for Attempt to ID a possible means/route of escape for
the attackers (search the local parking lots, etc)the attackers (search the local parking lots, etc)
Investigation Sept 23Investigation Sept 23 What the following video clip?What the following video clip?
Pay close attention to the piece of Pay close attention to the piece of evidence in question. evidence in question.
Special Forensic ServicesSpecial Forensic Services Forensic Pathology involves the Forensic Pathology involves the
investigation of unnatural, unexplained, or investigation of unnatural, unexplained, or violent deaths.violent deaths.
Medical examiners or coronersdetermine Medical examiners or coronersdetermine the cause of death.the cause of death.
Autopsy or medical dissection and Autopsy or medical dissection and examination of a body.examination of a body.
Stages of DeathStages of Death RIGOR mortis results in the shortening of RIGOR mortis results in the shortening of muscle tissue and stiffening of body parts muscle tissue and stiffening of body parts in the position at death.in the position at death.
Occurs within first 24 hours and disappears Occurs within first 24 hours and disappears within 36 hours.within 36 hours.
LIVOR mortis results in the settling of LIVOR mortis results in the settling of blood in areas of body closest to the blood in areas of body closest to the ground.ground.Begins immediately on death up to 12 hours Begins immediately on death up to 12 hours after death. after death.
Special Forensic ServicesSpecial Forensic ServicesALGOR mortis results in loss of body ALGOR mortis results in loss of body
heat.heat. General rule – begins an hour after General rule – begins an hour after
death.death.Body loses heat at a rate of 1 to Body loses heat at a rate of 1 to
1.5 1.5 degrees F per hour until degrees F per hour until body reaches body reaches environmental environmental temperature.temperature.
Stages of DeathStages of Death
Special Forensic ServicesSpecial Forensic Services Forensic Entomology is the study of insects and Forensic Entomology is the study of insects and
their relation to a criminal investigation often to their relation to a criminal investigation often to estimate time of death.estimate time of death.
Forensic Psychiatry involves the relationship Forensic Psychiatry involves the relationship between human behavior and legal proceedings.between human behavior and legal proceedings.
Forensic Odontology involves the use of teeth Forensic Odontology involves the use of teeth and bite marks to assist in identifying a victim in and bite marks to assist in identifying a victim in an unrecognizable state.an unrecognizable state.
analysis, accident reconstruction, analysis, accident reconstruction, and the causes and origins of fires and the causes and origins of fires and explosions.and explosions.
Forensic Computer Science involves Forensic Computer Science involves the examination of digital evidence.the examination of digital evidence.