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INVESTIGATIONS

INVESTIGATIONS. SCIENCE OR ART?. 3.5 THINGS SOLVE CASES THEY ARE?. WITNESS PHYSICAL EVIDENCE CONFESSIONS. .5. INFORMANTS CANNOT BE USED TO PROVE NOT USUALLY USED IN COURT. SUCCESS OR FAILURE OF CASE. People commit crimes “THINGS” become physical evidence What is PHYSICAL EVIDENCE.

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INVESTIGATIONS

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  1. INVESTIGATIONS SCIENCE OR ART?

  2. 3.5 THINGS SOLVE CASES THEY ARE?

  3. WITNESS • PHYSICAL EVIDENCE • CONFESSIONS

  4. .5 • INFORMANTS • CANNOT BE USED TO PROVE • NOT USUALLY USED IN COURT

  5. SUCCESS OR FAILURE OF CASE • People commit crimes • “THINGS” become physical • evidence • What is PHYSICAL EVIDENCE

  6. PHYSICAL EVIDENCE---any object that can establish that a crime has been committed or can provide a link between a crime and its victim or between a crime and its perpetrator

  7. CAN BE MEASURED

  8. TYPES OF PHYSICAL EVIDENCE • Blood, semen, saliva • Documents • Drugs • Explosives • Fibers • Fingerprints

  9. Firearms, and ammunition • Glass • Hair • Impressions • Paint • Soil and minerals • Tool marks

  10. WHOSE ARE THOSE ANYWAYS?? • Individual characteristics---Properties of evidence that can be attributed to a common source with an extremely high degree of certainty.

  11. HISTORY OF IT ALL • Sir Arthur Conan Doyle • A Study In Scarlet • 1887

  12. MID 1800’s • NYPD set up a Rogue’s Gallery-1857 • Photographs of known offenders • Arranged by criminal specialty and height • Offenders grimaced, puffed their cheeks to change their appearance

  13. Rogue is slang for thieves, a wandering beggar, someone who wanders away • By 1858 had over 700 photographs

  14. 1884 Chicago established the first municipal Criminal Identification Bureau • 1865 U.S. Secret Service was created by Congress to combat counterfeiting • Began guarding the president in 1903 after President McKinley was assassinated • 1905 CA Bureau of Criminal Identification

  15. First State Police Force in Pennsylvania • Prohibition in 1920, Bureau of Internal Revenue was responsible for enforcement • Lodged in the Dept of the Treasury, they were referred to as “T-men” • 1908 the beginnings of the FBI • 1932 FBI established a crime lab

  16. 1967 National Crime Information Center (NCIC) established by the FBI • Wanted persons • Stolen property • Guns • Vehicles • License plates • Cannot do credit cards

  17. “PACKING THE RECORD” • Get as much information as possible

  18. NCIC INFORMATION CLEARING HOUSE • COMPUTERIZED NETWORK LINKED TO PDs TO PROVIDE INFORMATION ON • STOLEN VEHICLES • WANTED PERSONS • STOLEN GUNS • OTHER CRIME RELATED INFO

  19. Oldest Forensic Lab • LAPD---1932 • Created by August Vollmer • Chief from Berkeley

  20. LOCARDS EXCHANGE PRINCIPLE • Edmond Locard (1877-1966) • The exchange of materials between two objects that occurs whenever two objects come into contact with one another

  21. TRACE EVIDENCE • PHYSICAL EVIDENCE THAT RESULTS FROM THE TRANSFER OF SMALL QUANTITIES OF MATERIAL

  22. IDENTIFICATION • THREE MAJOR SCIENTIFIC SYSTEMS FOR PERSONAL IDENTIFICATION • DEOXYRIBONUCLEIC ACID (DNA) TYPING • ANTHROPOMETRY • DACTYLOGRAPHY

  23. ANTHROPOMETRY • A system of identification of individual by measurement of parts of the body

  24. ANTHROPOMETRY • Developed by Alphonse Bertillon (1853-1914) • Father of criminal identification • Bertillon system • Every human being differs from every other one in the exact measurements of their body and that the sum of these measurements yields a characteristic formula for each individual

  25. Eleven physical measurements • 1883 implemented on an experimental basis • Combines full fact with profile pictures • Ancestor of the “mug shot”

  26. DACTYLOGRAPHY • Dates back to the First Century Romans • Three categories of latent fingerprints • Plastic prints—fingers touch against a surface such as newly painted surface, adhesive on envelopes and stamps, explosives, thick layer of dust, putty and adhesive tape

  27. LATENT • LATIN WORD FOR • HIDDEN

  28. Unique and Permanent • They develop at 12 weeks development • Stresses in the uterus causes friction ridges to develop • Identical twins have same DNA but different fingerprints---but may have same pattern types

  29. FRICTION RIDGES • TINY RIDGES IN THE SKIN OF A FINGERPRINT ARE KNOWS AS; • FRICTION RIDGES

  30. LOOPS

  31. WHORLS

  32. ARCHES

  33. WHAT TO LOOK FOR • LOOPS 60-65% OF POPULATION • WHORLS 30-35% • ARCHS About 5%

  34. Contaminated/visible prints—fingers that have been contaminated with a matter touch a clean surface • Latent/invisible prints—typically invisible to the unassisted eye. Created when the friction ridges deposit oils and body perspiration on a surface

  35. PRINTS ARE MADE OF: • Natural source—Sweat (98% water and 2% oils) Salts and amino acids and vitamins cause the fingerprint to show when sprayed with a chemical • Environmental source—grease, dirt, pollen, etc.

  36. DEVELOPING LATENT PRINTS • Traditional powders • Fluorescent powders • Chemicals • Cyanoacrylate—Superglue fuming • Ninhydrin • Iodine

  37. CHANGE THEM???? • Impossible to obliterate all the ridge characteristics and scars just help to provide new characteristics for identification

  38. LIVE SCAN FOR FINGERPRINTING • OPTICAL SCANNER

  39. IAFIS FBI 1999 • INTEGRATED AUTOMATED FINGERPRINT IDENTIFICATION SYSTEM

  40. BRAIN FINGERPRINTING

  41. OTHER TYPES OF IDENTIFICATION • DENTAL EVIDENCE & BITEMARKS • 1775 Paul Revere—was a dentist • John Wilkes Booth • mid 1960’s Armed Forces • Used mainly for id of bodies • 1970’s used for id of suspects

  42. HAIR • Area of the body and race • Manner removed • Shampoo residues • Bleached or dyed • Contaminants in the hair—blood, soil semen • If hair has been subject to trauma • Id of drugs ingested

  43. BLOOD • Approx 10 pints of blood • Most common form of evidence • Human blood? • If recovered in liquid state can tell • Venous • Fetal • menstrual

  44. HUMAN EXCRETIONS AND SECRETIONS • Saliva, urine, semen, perspiration, vaginal secretions, feces and vomitus • LIPSTICK AND SECRETIONS • Everyone has unique lip prints that do not change with age • FIREARMS

  45. TOOL MARKS • DOCUMENTS • HANDWRITING AND HANDPRINTING • COMPUTERS

  46. MOLECULAR STUCTURE DNA • DEOXYRIBONUCLEIC ACID • Organic substance found primarily in the chromosomes within the nuclei of cells. These molecules carry the body’s genetic information and establish each person as separate and distinct • DNA is three foot long chemical that is tightly wound inside the 46 chromosomes in each cell of the body

  47. HISTORY OF DNA • FBI first public sector crime laboratory to accept cases for DNA • December 15, 1988 • Minnesota testing is done at the Bureau of Criminal Apprehension (BCA) • Testing can take from 2 weeks to 2 months

  48. CODIS 1998 • COMBINED DNA INFORMATION SYSTEM • COMPARE AND • EXCHANGE DNA PROFILES

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