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Introduction to Forensic Science & to the Law Chapter 1
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Students Will Be Able To: Define and distinguish forensic science and criminalistics. Recognize the major contributors to the development of forensic science. Identify the significance that expert witnesses play in forensic science.
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Forensic Science It is the study and application of science to matters of law (criminal and civil) Includes the business of providing timely, accurate, and thorough information to all levels of decision makers in our criminal justice system Also called criminalistics
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Criminalistics vs Criminologists A criminalistic examines physical evidence for legal purposes Criminologists study the crime scene for motive, traits, and behavior as to help interpret the evidence – They learn to think like criminals
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Forensic Scientists Applies the principles and techniques of the physical and natural sciences to the analysis of the many types of evidence that may be recovered during a criminal investigation May also provide expert court testimony – Known as an expert witness Individual whom the court determines possesses knowledge relevant to the trial
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Developments in Forensic Science 700s AD- Chinese used fingerprints to establish identity of documents and clay sculptures ~1000- Roman courts determined that bloody palm prints were used to frame a man in his brother’s murder 1149- King Richard of England introduced the idea of the coroner to investigate questionable death 1200s- A murder in China is solved when flies were attracted to invisible blood residue on a sword of a man in the community 1598- Fidelus was first to practice forensic medicine in Italy
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Developments in Forensic Science 1670- Anton van Leeuwenhoek constructed the first high powered microscope 1776- Paul Revere identified the body of General Joseph Warren based on the false teeth he had made for him 1784- John Toms convicted of murder on basis of torn edge of wad of paper in pistol matching a piece of paper in his pocket 1859- Gustav Kirchoff and Robert Bunsen developed the science of spectroscopy 1864- Crime scene photography developed
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Developments in Forensic Science 1879- Alphonse Bertillion developed a system to identify people using particular body measurements 1896- Edward Henry developed the first classification system for fingerprint identification 1900- Karl Landsteiner identified human blood groups 1904- Edmond Locard formulated his famous principle, “Every contact leaves a trace” 1922- Francis Aston developed the mass spectrometer
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Developments in Forensic Science 1959- James Watson and Francis Crick discover the DNA double helix 1977- AFIS developed by FBI, fully automated in 1996 1984- Jeffrey’s developed and used the first DNA tests to be applied to a criminal case
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People of Historical Significance Mathieu Orfila- father of forensic toxicology Alphonse Bertillion- devised first scientific system of personal identification Francis Galton- conducted first definitive study of fingerprints and their classification Leone Lattes- developed a procedure to determine blood type from dried bloodstains Calvin Goddard- used a comparison microscope to determine if a particular gun fired a bullet
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People of Historical Significance Albert Osborn- developed the fundamental principles of document examination Walter McCrone- utilized microscopy to examine evidence Hans Gross- wrote treatise on criminal investigation Edmond Locard- considered the father of criminalistics; responsible for Locard’s exchange principle – States that when a criminal comes in contact with an object or a person, a cross transfer of evidence occurs
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Students Will Be Able To: Define observation. Describe the examples of factors that influence eyewitness accounts of events. Compare the reliability of eyewitness testimony to what actually happened. Relate observation skills to their use in forensic science. Practice and improve your own observation skills.
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Observations Are one of the most important tools of forensic investigators – They use observations to Identify evidence Record evidence Determine the significance of the evidence in relation to the crime
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Observations Are also made by witnesses Factors affecting observations – Whether you are alone or in a group – The number of people and/or animals in the area – What type of activity is going on around you – How much activity is occurring around you
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Eyewitness Is a person who witnessed a particular crime occurring – Can be powerful in persuading a jury one way or another Eyewitness observations can be affected by – Level of interest – Stress – Concentration – Person beliefs – Motives
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Deductive Reasoning Forensic scientists have good observation skills along with good analytical skills – Are very important in solving crimes Some forensic scientists are good at deductive reasoning – Is the act of deriving the consequences from the facts using a series of logical steps Working backwards from the evidence to piece together what happened leading up to the crime
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How to Become a Good Observer Make a conscious effort to examine your environment systematically Note everything, no matter how small or how familiar Concentrate on gathering information first and then worry about analyzing it Write down and photograph as much as possible
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Your Turn! You will have 20 seconds to study the following image. Afterwards, you will be asked questions that relate to the image.
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Questions How many people were in the image? How many were males? Females? What is located outside the front door? What color pants is the man on the computer wearing? How many shoeprints are in the image? The card labeled “F” points to what in the image?
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Students Will Be Able To: Describe how forensic science relies on multiple disciplines to solve crimes. Describe how the scientific method is used to solve forensic science problems. Account for the rapid growth of forensic laboratories in the past 45 years. Describe the services of a typical comprehensive crime laboratory in the criminal justice system. Understand what specialized forensic services, aside from the crime laboratory, are generally available to law enforcement personnel. Identify the 5 major crime labs in the US.
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Multidisciplinary Approach Forensic Sciences Math Life Sciences Earth Sciences Chemistry Process Skills Law Social Studies TechnologyPhysics Language Arts
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Scientific Method Forensic science begins at the crime scene and investigators rely on scientific method to help them solve the crime
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Scientific Method Steps in forensic science – Crime discovered and problem established – Detectives and investigators observe and collect evidence and evaluate the scene and surrounding areas – A hypothesis is developed What happened? How did it happen? When did it happen? – Evidence sent for analysis to pinpoint a suspect – Conclusion drawn based off evaluation of evidence
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The Crime Scene Team A group of professional investigators, each trained in a variety of special disciplines Team members include – First police officer on the scene – Medics (if necessary) – Investigator(s) – Medical examiner – Photographer and/or Field Evidence Technician – Lab Experts
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The Crime Lab Characterized by rapid growth due to – Supreme Court decisions in the 1960s placing greater emphasis on scientifically evaluated evidence – Accelerated drug abuse – Initiation of DNA profiling 350 public crime labs exist at federal, state, county, and municipal levels
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The Crime Lab History – First established in 1910 by Locard – First police crime lab established in 1923 in Los Angeles, CA – Scientific Crime Detection Lab established in 1929 – First FBI crime lab opened in 1932
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Crime Lab Services 5 exist – Physical science – Biology – Firearms – Document – Photographic
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Physical Science Unit Incorporates the principles of chemistry, physics, and geology to identify and compare physical evidence
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Biology Unit Applies the knowledge of biological sciences in order to investigate blood samples, body fluids, hair, and fiber samples
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Firearms Unit Investigates discharged bullets, cartridge cases, shotgun shells, and ammunition
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Document Unit Provides the skills needed for handwriting analysis and other questioned document issues
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Photographic Unit Applies specialized photographic techniques for recording and examining physical evidence
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Other Crime Lab Services Toxicology Unit- examines body fluids and organs for the presence of drugs and poisons Latent Fingerprint Unit- processes and examines evidence for latent fingerprints Polygraph Unit- conducts polygraph or lie detector tests Voiceprint Analysis Unit- attempts to tie a recorded voice to a particular suspect Evidence Collection Unit- dispatches specially trained personnel to the crime scene to collect and preserve physical evidence
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Other Forensic Science Services Forensic Pathology- concentrate closely on the understanding of types and causation of injuries and causes of sudden and unnatural death – Deals with the different stages of death Rigor mortis- stiffening of the body (occurs within first 24 hours) Livor mortis- settling of blood closest to the ground (occurs up to 12 hours) Algor mortis- results in loss of heat
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Other Forensic Science Services Forensic Anthropology-concentrates on the identification of deceased individuals whose remains are decomposed, burned, mutilated or otherwise unrecognizable Forensic Entomology- is the study of insects and their relation to a criminal investigation, commonly used to establish the time of death Forensic Psychiatry- work with courts in evaluating an individual's competency to stand trial, defenses based on mental diseases or defects (e.g., the "insanity" defense), and sentencing recommendations
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Other Forensic Science Services Forensic Odontology- evaluates teeth to determine the identification of the deceased Forensic Engineering- investigation of materials, products, structures or components that fail or do not operate/function as intended, causing personal injury for example Cybertechnology- involves the examination of digital evidence
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Major Crime Labs FBI- Federal Bureau of Investigations DEA- Drug Enforcement Agency ATF- Bureau of Alcohol, Tobacco, Firearms, and Explosives US Postal Service US Fish and Wildlife Service
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Students Will Be Able To: Identify and describe the laws that pertain to the US criminal justice system. Know the Bill of Rights as they apply to the criminal justice system.
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Laws that Pertain to the US Criminal Justice System The US Constitution Statutory Law Common Law or Case Law Civil Law Criminal Law Equity Law Administrative Law
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US Constitution Supreme body of laws that governs our country Overrules the constitutions of individual states
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Statutory Laws Are written laws as enacted by a government body such as Congress Are based on the Constitution
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Common Law Also known as case law Are made by judges – Makes for predictability and consistency in how the law is applied
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Civil Law Also known as private law Deals with relationships between individuals involving properties or contracts – Regulates noncriminal relationships between individuals, businesses, agency of government, and other organizations Includes contracts, marriages, divorces, wills, property transfers, negligence, and products manufactured with hidden hazards More concerned with assigning blame than intent
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Criminal Law Also known as public law Deals with regulation and enforcement of rights Concerned with offenses against an individual that are deemed offensive to society – Cases tried are always the person vs the state Those laws that are broken fall into 1 of 2 main categories – Misdemeanor- is a minor crime such as theft, minor assault and battery, or possession of small amounts of illegal drugs – Felony- is a major crime such as murder, rape, armed robbery, serious assaults, dealing in illegal drugs, fraud, auto theft, or forgery
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Equity Law Remedial or preventive law Are for cases not covered by common law – Restraining orders – Injunctions
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Administrative Law Laws established by governmental agencies such as the IRS, Social Security Administration, or the military
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The Bill of Rights The right to be presumed innocent until proven guilty The right not to be searched unreasonably, either on one’s person or in one’s home The right not to be arrested without probable cause The right against unreasonable seizure of personal property The right against self-incrimination The right to fair questioning by police
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The Bill of Rights The right to protection from physical harm throughout the justice process The right to an attorney The right to trial by jury The right to know any charges against oneself The right to cross examine prosecution witnesses The right to speak and present witnesses
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The Bill of Rights The right not to be tried again for the same crime The right against cruel and unusual punishment The right to due process The right to a speedy trial The right against excessive bail The right against excessive fines The right to be treated the same as others, regardless of race, gender, religious preference, country of origin, and other personal attributes
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Students Will Be Able To: Describe the steps taken from arresting an individual to having their day in court. Describe the importance of the Miranda vs. Arizona case. State the Miranda rights. Distinguish between the four pleas (guilty, not guilty, not guilty by reason of insanity, nolo contendere). Distinguish between infractions, misdemeanors, and felonies.
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Steps in Pursuing Justice If a crime is committed these are the steps to take while pursuing justice – Police investigate what happened – Information is collected – Crime scene is documented and searched for evidence – All info is assembled into a report and sent to DA – Investigation continues until probable cause is established – An arrest warrant is issued for the suspect – The suspect is arrested Individual is booked, fingerprinted, photographed and informed about his/her rights
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The Miranda Rights Miranda v. Arizona (1966) – Before a law enforcement officer may question a suspect regarding the possible commission of a crime, he or she must inform the detainee about his or her Miranda rights, making sure the detainee understands them
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The Miranda Rights Warning of Rights – You have the right to remain silent and refuse to answer questions – Anything you do or say may be used against you in the court of law – You have the right to consult an attorney before speaking to the police and to have your attorney present during questioning now or in the future – If you cannot afford an attorney, one will be appointed for you before any questioning if you wish – If you decide to answer questions now without an attorney present, you will still have the right to stop answering at any time until you talk to an attorney – Knowing and understanding your rights as I have explained them to you, are you willing to answer my questions without an attorney present?
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Steps in Pursuing Justice – Person is brought before a magistrate judge who informs the individual of the charges, his/her rights, and bail The person may also enter a plea of guilty, not guilty, not guilty by reason of insanity, double jeopardy (been tried for same crime in same court), or nolo contendere (no contest) – If a plea of guilty is entered, the person is brought before a preliminary or evidentary hearing (no jury present) Most states use a grand jury – Will determine if there is enough evidence to bring the accused to a formal trial – The prosecutor presents evidence and the grand jury (16-23 citizens) decide the fate of the accused – If the grand jury decides there is enough evidence, a trial date will be set
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Steps in Pursuing Justice – If a plea of not guilty by reason of insanity is entered, the defendant will have to prove, by “clear and convincing evidence,” that “at the time of the commission of the acts constituting the offense, the defendant, as a result of a severe mental disease or defect, was unable to appreciate the nature and quality or wrongfulness of his acts” Crimes must show intent- the insanity plea removes intent
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Steps in Pursuing Justice – Sometimes, the DA will plea bargain with the accused The defendant works out a deal with the DA – May reduce jail time
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Types of Crimes All crimes are violations (breach of a right, duty, or law) – 3 types Infractions Misdemeanors Felonies
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Infractions Minor offense or petty crime Is less serious than a misdemeanor Examples include – Jaywalking – Traffic violations – Littering Penalty is usually a fine
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Misdemeanors Cases are tried in court Punishable by no more than 1 year in jail Examples include – A first offense of drunk driving, vandalism, shoplifting, simple assaults, trespassing, or prostitutions Fines range from less than $250 to $2500 Community service is also part of the sentence sometimes
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Felonies Cases are tried in court Punishable from 5 years to life – Some states offer death penalty Examples include – Arson, aggravated assault, burglary, robbery, homicide, and rape Fines may be up to $100,000 Probation may also be determined
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Students Will Be Able To: Contrast probative, material, and hearsay evidence. Compare and contrast the Frye and Daubert decisions relating to the admissibility of scientific evidence in the courtroom. Identify and describe the three facets of guilt.
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Federal Rules of Evidence Probative – In evidence law, tending to prove something Material – In evidence law, relevant and significant. Hearsay – Testimony given by a witness who relates not what he or she heard, saw, or knew personally, but what others have said – Is not admissable in the court of law
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Admissibility of Evidence As forensic science has evolved, how evidence is processed, what type of evidence is admissible in court, and the equipment used to analyze evidence has been scrutinized Several cases have led to modifications in how forensic science experts process evidence and in the types of evidence presented at court – Frye vs United States – Daubert vs Dow
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Frye vs. United States James Frye was convicted of 2 nd degree murder in 1923 – He confessed to murder but retracted his confession later – Conviction was appealed based on the grounds that the lie detector test he took proved he was telling the truth – Court denied his appeal Led to Frye Standard – States that evidence, procedures, and equipment presented at trial must be generally accepted by the scientific community
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Daubert vs. Dow Involved minors,Jason Daubert and Erik Schuller – Were born with birth defects due to mothers taking Bendectin during pregnancy – Ruling suggested criteria for evaluating the science used to support evidence presented by an expert Has it been tested? Has it been peer reviewed? What is the rate of error? Is it generally accepted?
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Admissibility of Evidence Frye vs. United StatesDaubert vs. Dow 1.Scientific evidence must meet “general acceptance” standards. 2.Any evidence, procedure, or equipment presented at trial must gain acceptance from the scientific community before becoming admissible in court. 1.Trial judge has ultimate decision-making power regarding expert testimony used at trial. 2.Expert testimony is NOT automatically admissible. The judge must consider whether the underlying science is generally accepted and based on testable theory and whether the procedures have undergone peer review and have a reasonable error rate. 1.Recognizes that science is constantly changing. 2.Decisions affected the use of expert testimony at trial.
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Facets of Guilt Try to prove – Means- person had the ability to do the crime – Motive- person had a reason to do the crime Does not have to be proved in a court of law – Opportunity- person can be placed at the crime
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