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Do Now. Make a copy of your team list of forensic techniques from yesterday Rank them in terms of your interest in finding out more about them 1=most interesting 5=least interesting. Forensic Science. An Introduction. What is forensic science?. Science in service to the law

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Do Now

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  1. Do Now • Make a copy of your team list of forensic techniques from yesterday • Rank them in terms of your interest in finding out more about them • 1=most interesting • 5=least interesting

  2. Forensic Science An Introduction

  3. What is forensic science? • Science in service to the law • “…the application of science to those criminal and civil laws that are enforced by police agencies in the criminal justice system.”Saferstein

  4. What’s the key concept in FS? • Locard’s Exchange Principle (~1910) • Whenever a criminal comes in contact with a person or object there is a cross-transfer of evidence.

  5. What are the consequences of Locard’s Exchange Principle? • The perpetrator leaves evidence behind and also takes evidence away • The longer you wait before collecting evidence the less there is left • Every person at the crime scene including police investigators will contaminate it

  6. Realistic?

  7. What is Forensic Science Trying to Do? • The goal of Forensic Chemistry is to determine the provenance of a sample. • Link it to a person, place or thing prov·e·nancePronunciation: 'präv-n&n(t)s, 'prä-v&-"nän(t)sFunction: nounEtymology: French, from provenir to come forth, originate, from Latin provenire, from pro- forth + venire to come -- more at PRO-, COME1: ORIGIN, SOURCE2: the history of ownership of a valued object or work of art or literature

  8. Roles of the Forensic Scientist • Analyze physical evidence • Provide expert testimony • Train evidence collection units in recognition, collection and preservation of evidence Would you expect to see Gil Grissom collecting evidence at a crime scene?

  9. Physical Science Biology Firearms Photography Documents Crime Lab Odontologist Voiceprint Analysis Polygraph Latent Fingerprints Toxicology Evidence Collection Psychiatrist The Crime Lab Pathologist Engineer Anthropologist Entomologist

  10. The Expert Witness • Trial judge must be satisfied that the expert • Has skill or knowledge that will aid the court in determining the truth • Education (degrees, courses) • Training (internship under experienced practitioner) • Experience (years on the job, publications, professional societies) • Trial judge is the gatekeeper

  11. The Expert Witness • An expert witness can testify as to his/her opinion of what the evidence indicates • A lay witness can only testify as to fact

  12. What is the most common task a forensic scientist performs? • Take 5 minutes and discuss this in groups of 4 and then be ready to report out your reasoning.

  13. The Expert Witness • Jury assigns weight to the expert’s opinions • Jury looks at • Credentials • Demeanor • Whether material is presented simply and clearly • Jury is the trier of fact

  14. Class vs. Individual Characteristics • Class characteristics: • Many objects share the same set of characteristics • Shoe tread pattern, bullet caliber, shoe size, overall pattern of a fingerprint • Individual characteristics: • Unique to a single object • Wear pattern on a shoe, striations on a bullet, minutiae in fingerprints

  15. Anthrax Letters 5 dead 17 sickened Beginning 9/18/2001 What types of evidence would you look for?

  16. Apply your understanding: • What are class and individual characteristics of each of the possible types of evidence in the anthrax case?

  17. Anthrax Letters • Trace hair and fibers in envelope • Ink analysis may reveal manufacturer • DNA from stamp or envelope seal • Cellophane tape ends match over four letters • Paper examination may identify manufacturer • Fingerprints • Photocopier toner may reveal manufacturer • Handwriting analysis shows four letters written by same person • Indented writing • Bar codes for mail handling

  18. Who did it? Dr. Bruce Ivins Committed suicide July 2008 Dr. Steven Hatfill Now suing government

  19. Analytic Wants to find composition of samples Compounds Proportions in mixtures Uses same instruments as forensic Forensic Wants to find composition of samples Compounds Proportions in mixtures Uses same instruments as analytical Analytic vs. Forensic ChemistrySimilarities

  20. Admissibility: A Moving Target • Frye v. US (1923) • Scientific evidence is admissible only if it has gained general acceptance in the field • Rejected polygraph opinions • Historical Perspective • Tennessee v. John Scopes (1925) • The Monkey Trial

  21. Admissibility: A Moving Target • Coppolino v. State of Florida (1968) • Doctor accused of poisoning his wife with succinylcholine chloride (muscle relaxant) • New and unique tests performed specifically for this case • Detected by-products of metabolism of poison (succinic acid) • Admissible if based on scientifically valid principles and techniques

  22. Admissibility: A Moving Target • Federal Rule of Evidence 702 (1975) • Approved by Congress • More flexible general relevance test for admissibility of opinion testimony by experts • “If scientific, technical or other specialized knowledge will assist the trier of fact to understand the evidence or to determine a fact at issue, a witness qualified as an expert by knowledge, skill, experience, training, or education, may testify thereto in the form of an opinion or otherwise.”

  23. Admissibility: A Moving Target • Daubert v. Merrell Dow Pharmaceuticals (1993) • When expert evidence based on “scientific knowledge” is offered at trial, the judge acts as gatekeeper to determine if the evidence is “reliable” • Four suggested factors in determining reliability • Testable using the scientific method • Peer reviewed • Error rates • Acceptability to the scientific community • Trial judge given lots of flexibility • Muddy waters—what is scientific knowledge? • What about other types of experts?

  24. Admissibility: A Moving Target • Why Daubert won on appeal • When Congress passed Rule 702 it ignored the Frye general acceptability criterion • Frye was no longer “good law”--

  25. Admissibility: A Moving Target • Kumho Tire Co v. Carmichael (1999) • Daubert factors are extended to non-scientist expert witnesses. • Daubert factors are not the only ones that can be considered • Trial judge now has enormous flexibility

  26. And it’s not settled yet….. • Daubert and Kumho apply to federal cases only • 18 State Courts have adopted Daubert standards • Other State Courts have rejected Daubert and still use a modified Frye standard

  27. Miranda vs. Arizona (1966) • Before questioning by the police, suspects must be informed that they have: • The right to remain silent • The right to consult an attorney • If indigent an attorney will be provided for them • Anything they say may be used against them in court Arizona Department of Library Archives and Public Records)

  28. Results of Miranda • Confessions are less likely to hold up in court since the burden of proof of Miranda statement lies on police • Police and prosecutors rely more independent (scientific) evidence to prove guilt

  29. Dickerson • Dickerson vs US (2000) • Congress passed law in 1968 saying voluntary confessions are exempt from Miranda • Supreme Court overrules Congress in 2000 • Congress can’t overrule the Supreme Court on constitutionally guaranteed rights except by the amendment process

  30. What’s driving the growth of FS? • Miranda decision • Fewer confessions • Increase in drug seizures and arrests • More testing • DNA profiling • More testing with sophisticated equipment • Other new technologies

  31. Crime Wave or Better Enforcement?

  32. Federal Drug Seizures

  33. Coast Guard Drug Seizures

  34. Arrests by Drug Type

  35. Average % THC in Marijuana Seizures Recent seizures in Atlanta had plants with 18% THC content. http://www.usdoj.gov/ndic/pubs11/18862/images/fig1.gif

  36. The Economics of Drugs • According to the United Nations Office on Drugs and Crime, "[T]he value of the global illicit drug market for the year 2003 was estimated at US$13 bn [billion] at the production level, at $94 bn at the wholesale level (taking seizures into account), and at US$322bn based on retail prices and taking seizures and other losses into account." • This is larger than the total economies of 88% of the countries in the world! • Source: United Nations Office on Drugs and Crime (UNODC), World Drug Report 2005 (Vienna, Austria: UNODC, June 2005), p. 127.

  37. And Now for Some Expert Testimony My Cousin Vinny http://myafn.dodmedia.osd.mil/img/tv/criticschoice/cousinvin.jpg

  38. A Big Driver in the Plot • Could Mona Lisa testify?

  39. The Forensic All Stars • Mathieu Orfila (1787-1853) • Father of toxicology • Alphonse Bertillon (1853-1914) • First system of personal identification • Francis Galton (1822-1911) • Classification of fingerprints • Dr. Leon Lattes (1887-1954) • Determination of blood groupings from dried blood stains

  40. The Forensic All Stars • Calvin Goddard (1891-1955) • Father of ballistics • Use of comparison microscope • Albert S. Osborn (1858-1946) • Fundamental principles of document examination • Walter C. McCrone (1916-2002) • Application of microscopy to analytic problems

  41. The Forensic All Stars • Hans Gross (1847-1915) • First text detailing application of science to criminal investigation • Edmond Locard (1877-1966) • Locard’s Exchange Principle • There is an exchange of materials whenever two objects come in contact

  42. Activity Time! • Assign each of the items in your evidence list to the proper department in the crime lab • Feel free to add more types of evidence • Populate your crime lab with your favorite TV characters

  43. Analytic Known source Good idea of what the composition is likely to be Used for quality control Well defined samples and controls Forensic Need to determine source Little knowledge of composition Often complex mixtures so hard to find appropriate controls Analytic vs. Forensic ChemistryDifferences

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