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Fingerprints

Fingerprints. Fingerprints History. Ancient Carvings, 3000 B.C. Included figures depicting fingerprint patterns Awareness of patterns on fingertips China, ~ 3000 B.C. Fingerprints embedded in clay used to seal documents and packages. Fingerprints History. William Hershel, 1860

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Fingerprints

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  1. Fingerprints

  2. Fingerprints History • Ancient Carvings, 3000 B.C. • Included figures depicting fingerprint patterns • Awareness of patterns on fingertips • China, ~ 3000 B.C. • Fingerprints embedded in clay used to seal documents and packages

  3. FingerprintsHistory • William Hershel, 1860 • Confirmed FP don’t change over time • Used FP in India to control fraud in government contracts & pensions • Didn’t envision using FP in criminal investigations

  4. FingerprintsHistory • Henry Faulds, 1880 • 1st to suggest using FP in criminal investigation • Offered to set up FP unit at Scotland Yard, 1886-88 • Offer rejected

  5. Fingerprint Classification History • Ivan Vucetich: Argentina PD, 1891 • Set up Anthropometry ID system • 1891- developed FP classification system • 1893- bloody FP used to solve homicide • Ordered to revert back to anthropometry • 1896- FP used exclusively in S. America

  6. Fingerprints History • Anthropometry: 1870 - 1900 • Devised by Alphonse Bertillon • Series of 11 body measurementsused to classify individuals

  7. Anthropometry 1870-1900 Alphonse Bertillon

  8. FingerprintsHistory Leavenworth Prison, Kansas - 1903 Anthropometry: measurements in centimeters

  9. Fingerprints History • Anthropometry: 1870 - 1900 • Will West/William West Case – Kansas (1903) Will West William West • Anthropometry discredited • Individuals distinguished by fingerprints

  10. Francis Galton “Finger Prints” 1892 • Studied minutiae of fingerprints • Collection >8000 sets of prints • Statistical proof of identity • Foundation for acceptance in court • Unable to determine heredity, race, gender from fp.

  11. Francis GaltonThree Principles • Fingerprints are Unique. No two ever found to be the same. • Fingerprints don’t change during lifetime. • Detail sufficient to classify into 3 patterns: • Arches • Loops • Whorls

  12. Fingerprint Classification History • Sir Edward Henry, 1900 • India- FP used to identify workers for payroll • Credited with developing FP classification system for British (“Henry System”) • 1901- Scotland Yard adopted Henry System for FP bureau

  13. Fingerprints in the USA • 1902- NYC Civil Service Commission uses to certify test applications • 1903- NY State & Leavenworth Prisons • 1904- Scotland Yard instructs US police at World’s Fair, St. Louis, MO • 1905- U.S. Army • 1911- 1st conviction based on FP evidence, Illinois • 1924- FBI Identification Division

  14. What Are Fingerprints? • Ridges in upperlayer of skin (epidermis) • Pattern produced by cells of dermal papillae • Provide frictionfor grasping • Ridges contain pores for secretion of perspiration • Developed in fetus at 17 wks. • Never change

  15. Composition of Eccrine Sweat(Body Surfaces without Hair) • >99% Water • Solute Composition • 44% Sodium Chloride • 29% Lactic Acid • 12% Urea • 8% Amino Acids • 7% Others (Organics & Inorganics)

  16. Fingerprint Classification Core - Approximate center of pattern Type Lines - Diverging ridges that surround the loop Delta - Triangular shaped area where type lines meet

  17. Fingerprint Classification- Loop • Plain Loop • Ridges start on one side, loop around, and leave on the same side • Most common,~ 60-65% of all fingerprints • Ulnar Loop • Opens toward the pinkie • Radial Loop • Opens toward the thumb • Most often index finger *Loops - 1 Delta and 1 Core

  18. RADIUS ULNA

  19. Fingerprint Classification- Whorl • Whorl • 30-35% of all fingerprints • Circular pattern radiating around the center of the finger • 2 or more deltas

  20. Fingerprint Classification- Whorl Core Delta Delta *Whorls - 2 Deltas and 1 Core

  21. Fingerprint Classification- Whorl • Plain Whorl • Line between deltas crosses circular part of ridge pattern

  22. Fingerprint Classification- Whorl • Central Pocket Loop Whorl • Line between deltas does not cross circular part of ridge pattern

  23. Fingerprint Classification- Whorl • Double Loop Whorl • Two opposing loops side by side • How many cores and deltas? DeltasCores

  24. Fingerprint Classification- Whorl • Accidental Whorl • Combination of any two patterns except Plain Arch

  25. Fingerprint Classification- Arch • Plain Arch • Least common, ~ 5% of all fingerprints • Ridges start on one side, rise in the middle and exit on the other side • No core or deltas

  26. Fingerprint Classification- Arch • Tented Arch • Ridges start on left, sharp rise in the middle and exit on the right • Angle <90 degrees This is not considered a Delta

  27. What Types Are These?

  28. Minutiae

  29. Questioned Fingerprints • Patent Prints - Made after finger comes in contact with visible material • Blood, Ink, Grease, Paint, Etc. • Plastic Prints – Indented visible impressions left in soft material • Clay, Wax, Soap, Vaseline, Etc. • Latent Prints - Invisible prints that must be processed to be seen

  30. Patent Fingerprints • Visible Prints • Easy to find • Document with photography • Collect entire item • May be enhanced if needed • Blood (Amido Black)

  31. Plastic Fingerprints • Indented Prints • Easy to find • Document with photography • Collect item • May be enhanced if needed • Oblique lighting

  32. Latent Fingerprints • Invisible Prints • Must be made visible • Lighting • Oblique • UV (for non-absorbant surfaces) • Alternate Light Source (high-intensity)

  33. Alternate Light Source • High intensity light beam • Causes latent prints to fluoresce when illuminated Weak prints: Fume with Super Glue, dust with fluorescent powder, illuminate with ALS

  34. Latent Fingerprints • Increase Contrast • Dark Background; make print lighter • Light Background; make print darker

  35. DustingPhysical Enhancement • Dust adheres to perspiration, oils in print residue • Lightly dust - don’t wipe away print • Apply small amounts of powder • Use contrasting powders • Gray or Black (non-porous surfaces) • Fluorescent (multi-color surfaces) • View with alternate light source (ALS) • Magnetic Brush- powder with metallic particles • Paper, leather, (porous substrates)

  36. Dusting with Powder

  37. Dusting with Magnetic Powder

  38. DustingPhysical Enhancement • Dusting used on hard, smooth surfaces • May be used on paper, if fresh • Rapid, simple technique • May be used to dust the whole scene • If prints develop: • Photograph (black & white) • Lift with tape • Place on contrasting background

  39. Super GlueChemical Enhancement • Cyanoacrylate – Active Ingredient • Fumes react with latent print residue • Prints are fixed (hardened) • Print is visible (white) • Print may be dusted after fuming to enhance pattern

  40. Prints On PaperChemical Enhancement • Ninhydrin • Ninhydrin reacts with amino acids • Good for older samples • Spray and heat • Reaction takes 2 - 48 hours; lasts months • DFO (diazefluorenone) • Used on money, less background • Visible w/ ALS

  41. Prints On PaperChemical Enhancement • Physical Developer • Silver Nitrate reacts with chloridesalts from perspiration • Porous surfaces- paper and wood • Results in minutes • Print must be fixed or it will turn black

  42. Automated Fingerprint Identification System • AFIS • Fingerprint scanned into computer • “Live scan” • Compared with scanned images of other fingerprints • Open cases • Arrestees, job applicants SCALPS - Suffolk County Automated Latent Print System

  43. Woman and Son Found Slain on L.I. Feb. 1984 A woman and her son were found slain yesterday in their home in Oceanside, L.I., the Nassau County police said. The police, who did not disclose the cause of death, said they may have been killed during a robbery. The victims were Susan Eigen, 41 years old, of 3412 Ocean Harbor Drive, and her son, Richard, 17. Their bodies were discovered at 6:20 P.M. yesterday by another son, Michael, 11. The police, who are investigating the deaths, said it is not yet known if they are related to the strangulation last Friday of Luanne Anziano Finn, 27, of Oceanside, whose body was found in a burning car behind the Florence Smith School in Oceanside. New York: Mineola Man Convicted Of 1984 Murders March 2004 A man was found guilty yesterday of two 20-year-old murders because of his application for a school bus driver's job. The application required hisfingerprints, which were matched to printsatthe crime scene. He faces a sentence of 50 years to life. The man, Louis Telese, 44, of Nanuet, was convicted of murdering a Long Island woman and her 17-year-old son in 1984 in the family's Oceanside home. Mr. Telese was arrested in June 2002, after the authorities linked him to the crime scene through the job application, the district attorney's office said. One victim, Susan Eigen, 41, had been strangled, bound to her bed and sexually assaulted. Her son, Richard, had been suffocated and bound to a banister. An assistant district attorney, Robert P. Biancavilla said Mr. Telese, who was a cousin of the family living next door, had planned to rob his relatives, but turned his attention to the Eigens because a relative was home. Stacy Albin (NYT)

  44. Live Scan-Inkless Fingerprinting

  45. Minutiae Points Extracted from Known Print AFIS

  46. AFIS • Computer identifies ridge endings and bifurcations for comparison • Software recognizes geometric patterns formed by these minutiae with core at center

  47. Questioned Print Known Candidate

  48. Fingerprint Comparison How many ridge characteristics are required for a match?

  49. Suffolk County Automated Latent Print System-SCALPS • Established in 1986, Yaphank • Computerized fingerprint searches • 297,800 sets of known prints on file • 20,400unknown latent prints on file • 11,803hits between 12/86 – 09/09 Updated 10/28/2009

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