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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 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
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
TYPES OF PHYSICAL EVIDENCE • Blood, semen, saliva • Documents • Drugs • Explosives • Fibers • Fingerprints
Firearms, and ammunition • Glass • Hair • Impressions • Paint • Soil and minerals • Tool marks
WHOSE ARE THOSE ANYWAYS?? • Individual characteristics---Properties of evidence that can be attributed to a common source with an extremely high degree of certainty.
HISTORY OF IT ALL • Sir Arthur Conan Doyle • A Study In Scarlet • 1887
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
Rogue is slang for thieves, a wandering beggar, someone who wanders away • By 1858 had over 700 photographs
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
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
1967 National Crime Information Center (NCIC) established by the FBI • Wanted persons • Stolen property • Guns • Vehicles • License plates • Cannot do credit cards
“PACKING THE RECORD” • Get as much information as possible
NCIC INFORMATION CLEARING HOUSE • COMPUTERIZED NETWORK LINKED TO PDs TO PROVIDE INFORMATION ON • STOLEN VEHICLES • WANTED PERSONS • STOLEN GUNS • OTHER CRIME RELATED INFO
Oldest Forensic Lab • LAPD---1932 • Created by August Vollmer • Chief from Berkeley
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
TRACE EVIDENCE • PHYSICAL EVIDENCE THAT RESULTS FROM THE TRANSFER OF SMALL QUANTITIES OF MATERIAL
IDENTIFICATION • THREE MAJOR SCIENTIFIC SYSTEMS FOR PERSONAL IDENTIFICATION • DEOXYRIBONUCLEIC ACID (DNA) TYPING • ANTHROPOMETRY • DACTYLOGRAPHY
ANTHROPOMETRY • A system of identification of individual by measurement of parts of the body
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
Eleven physical measurements • 1883 implemented on an experimental basis • Combines full fact with profile pictures • Ancestor of the “mug shot”
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
LATENT • LATIN WORD FOR • HIDDEN
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
FRICTION RIDGES • TINY RIDGES IN THE SKIN OF A FINGERPRINT ARE KNOWS AS; • FRICTION RIDGES
WHAT TO LOOK FOR • LOOPS 60-65% OF POPULATION • WHORLS 30-35% • ARCHS About 5%
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
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.
DEVELOPING LATENT PRINTS • Traditional powders • Fluorescent powders • Chemicals • Cyanoacrylate—Superglue fuming • Ninhydrin • Iodine
CHANGE THEM???? • Impossible to obliterate all the ridge characteristics and scars just help to provide new characteristics for identification
LIVE SCAN FOR FINGERPRINTING • OPTICAL SCANNER
IAFIS FBI 1999 • INTEGRATED AUTOMATED FINGERPRINT IDENTIFICATION SYSTEM
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
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
BLOOD • Approx 10 pints of blood • Most common form of evidence • Human blood? • If recovered in liquid state can tell • Venous • Fetal • menstrual
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
TOOL MARKS • DOCUMENTS • HANDWRITING AND HANDPRINTING • COMPUTERS
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
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
CODIS 1998 • COMBINED DNA INFORMATION SYSTEM • COMPARE AND • EXCHANGE DNA PROFILES