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JS 113 –Fingerprint Lecture I. Pre-class activities a. Quiz b. Announcements and Assignments II. Learning objectives a. List 3 major fingerprint patterns and respective subclasses b. Name individuals that have made significant contributions to acceptance and development of fingerprints c. Define ridge characteristics d. Explain visible, plastic vs. latent prints e. Understand the primary classification of the Henry system f. List techniques for developing latent prints on non porous objects g. Describe chemical techniques for developing prints on porous objects h. Describe the proper procedure for preserving a developed latent i. Explain how a latent fingerprint image can be enhanced by digital imaging
Announcements and Assignments • Quiz is open book - Fill it out during class and be sure to hand it in before you leave • Assignments/Schedule/Lectures: – Student led Chapter reviews – 09/24/07 : Your team must email me the chapter summary- 2 -3 pages total – BY FRIDAY 09/21/07 and provide a hard copy of the summary on Monday 09/24/07 – EXAM I is Weds 09/26/07 covering Chapters 1, 2, 3, 4, 7, and 14 – Video on Weds 10/03/07 • Guest Lecturers – October 8 th Supervisor Tom Abercrombie Oakland PD: Crime Scene, Drugs and Latents – October 10 th Dr. Sandra Sachs- Forensic toxicology • Exam 1: 09/26/07
BASIC PATTERNS 1 2 3
8 DIFFERENT TYPES OF FINGERPRINTS Remembered by: L A W
No Fingerprints! Rare Disorder but it happens. … defects in the protein keratin 14 may be responsible for both diseases, known as Naegeli syndrome and dermatopathia pigmentosa reticularis (DPR). But the lack of fingerprints is not the diseases' only, or even most serious, impact. Patients also experience thickening of their palms and soles of their feet. They suffer from anomalies in the development of their teeth, hair, and skin, where pigmentation can appear patchy and uneven. Most dangerously, they have skin issues that can inhibit their ability to sweat normally.
A brief history of fingerprints (1) • 1883 The first systematic attempt at personal identification was by Alphonse Bertillon-anthropometry • Dimensions of human bone system remained fixed from age 20 to death • For 2 decades it remained the most accurate method.
A brief history of fingerprints (2) • Chinese used to sign legal documents 3000 years ago with fingerprints (ceremonial of for human ID still unknown) • In India years before Bertillon, William Hershel started the practice of requiring natives to sign contracts with imprints of their right hands • 1880, Henry Fauld working in a Japanese hospital published a suggestion that skin ridge patterns could be important for the identification of criminals… Offered to Scotland yard but rejected
A brief history of fingerprints (3) • 1892 Francis Galton published his classic textbook Finger Prints, - anatomy of fingerprints and suggested methods for recording them. • Galton proposed assigning three pattern types: – Loops, Arches, and Whorls • Book demonstrated that no two prints were identical and that they remained unchanged from year to year • 1891 Juan Vucetich created a classification system • 1897 Sir Edward Richard Henry created another classification system adopted by US.
A brief history of fingerprints (4) • 1903, Will West at Ft Leavenworth prison. William West who was already in prison could not be distinguished by anthropometry nor photographs but by fingerprints
Will West vs William West
Other Look Alikes http: //abcnews. go. com/2020/story? id=2912199
Photos from Francois Brunelle www. francoisbrunelle. com
A brief history of fingerprints (5) • 1901, NYC Civil Service commission adopts fingerprints for personal ID to certify all civil service applicants • 1904, used at the World’s Fair in St. Louis for representatives of Scotland Yard • 1924 BI records and Leavenworth records merged forming the nucleus ID records at the FBI – where the largest collection now exists • 1999 - Admissibility challenge in US v. BC Mitchell. Eastern PA. Argued, fingerprints could not be proven unique under Daubert. • Following 4. 5 days, upheld fingerprints as scientific evidence ruled that 1) human friction ridges are unique and 2) human friction ridge skin arrangements are unique and permanent.
FINGERPRINT ANALYSIS • Most familiar to public • Leaving a readable print depends on: - Surface on item touched - Condition of fingers - Way item is handled • Fingerprints are completely individual characteristics. • First Principle- A fingerprint is an individual characteristic; no two fingerprints have yet been found to possess identical ridge characteristics
WHAT ARE FINGERPRINTS ? • Friction Ridges – raised lines on skin that come together to form patterns also known as minutiae • Designed by nature to provide our bodies with a firmer grasp and resistance to slippage • Second Principle: Patterns formed by ridges never change throughout an individual’s life*. Fingerprint remains unchanged during an individuals lifetime * individual marks and scars can be added John Dillenger tried with acid- see figure 14. 4
WHAT ARE FINGERPRINTS ? • Third Principle: All prints have ridge characteristics that permit them to be systematically classified • 60 -65 % of the population has loops, 30 -35 have whorls and only 5% have arches • LAW form the basis for all classification systems • • • Loops- ridge lines that enter from one side and curve around to exit from the same side of the pattern Arch- lines that enter from one side and exit from the other Whorls- ridge patterns are rounded or circular in shape and have two deltas
THREE FORMS OF FINGERPRINTS • Visible print – form of residue print – Touching a surface after the ridges have been in contact with a colored material (blood, paint…) • Plastic print – made in soft material – (putty, soap dust. . ) • Latent print – result of perspiration or oils present on ridges INVISIBLE NEED DEVELOPING * can be more easily developed on smooth, nonporous surfaces
COMPARISON OF PRINTS • In identifying a fingerprint, the analyst must also look at ridge characteristics which are independent of the patterns (aka minutiae) IDENTITY, NUMBER AND LOCATION IMPART INDIVIDUALITY
Recognition, Collection and Preservation of Fingerprint Evidence • Recognition of fingerprint evidence is similar to recognition of evidence in general – Training and Experience – Points of entry, weapons… MAY VARY CASE TO CASE – Appropriate tools (Alternate Lighting) – Documentation- photo, notes, sketches
Recognition, Collection and Preservation of Fingerprint Evidence • General Rule: objects believed to have latent fingerprints should be collected intact and submitted – Necessary materials brown paper bags, cardboard box for firearms/weapons, manila envelopes for documents • If item cannot be submitted to Fingerprint section of lab, must develop at scene and use a tape lift or carefully photographed using 35 mm or top quality digital cameras-scale • Marked/TAPE-SEALED/ CHAIN OF CUSTODY
Recognition, Collection and Preservation of Fingerprint Evidence • Considerations for preservation of latent print evidence – Is there biological evidence ? – Type of material on which the print is present
DEVELOPING LATENT PRINTS • IN GENERAL: • - Powders are used to develop prints on smooth, nonporous surfaces - Chemicals are used to develop prints on porous or absorbent materials like paper or wood
EFFECTS OF SURFACES • Hard or glossy, non-porous surfaces retain latent impression fairly well • Rough, coarse or porous surfaces do not receive or retain latent impressions well; textured glass or rough paint * The age of a latent print can not be determined with any specificity except when the area was cleaned
PHYSICAL TECHNIQUES: POWDERS • The oldest and least sophisticated method for latent prints • Should be primarily used on non-porous material • Best when used in conjunction with Super Glue Fuming * Over 85% of fingerprints developed by this method
FUMING TECHNIQUESSUPER GLUE (Cyanoacrylate) • Develops latent print to produce white color print • Best utilized on nonporous items or physical evidence • White ridge detail is enhance by moisture • Contrast of print improved by application of dyes or powders
DEVELOPMENT REVIEW • The type of surface on which a fingerprint is deposited has a lot to do with the type of print that will be deposited on the physical evidence • The use of sequential processing techniques can increase the number of prints found and improve the quality of the prints already developed
AUTOMATED FINGERPRINT INDENTIFICATION SYSTEM • AFIS –The ability to compare a fingerprint found at the crime scent with a criminal fingerprint computer data base • Cold Searches – searching a data base of several million prints against a single latent print in about 10 minutes
Group assignment- Classifying fingerprints • Using your knowledge of fingerprints, classify all 10 fingers of each member of your team into loop, arch or whorl (or appropriate type). • Count the total numbers of L, A and W and provide the % of each type on the chart on the board. • Does the observed % equal the expected %? • What are some potential reasons the observed might not equal the expected? • Design an experiment to test your hypothesis.
FINGERPRINT LAB PART ONE today A. Your Inked or pencil Prints – What fingerprint patterns ? – Print all fingers onto your fingerprint card – Fill it out – Enlarged print (at least one characteristic) B. Super Glue – Reading only PART Two next time C. Black Powder – 2 different surfaces: • Smooth glass slide and tile D. Magnetic Powder – 2 different surfaces – Smooth glass slide and tile
E. Evidence Sample • Everyone will get an item to process for fingerprints using techniques you have learned/ MUST LIFT A PRINT • HOWEVER!!! MUST SWAB BOTTLE FOR SALIVA FIRST (lightly moistened swab) – Allow swab to dry while you work on item – When dry package in envelope – Once swabbed, dry the swab and then place into envelope and fill out the chain of custody – Be sure to take notes on the evidence and sketch on the card.
REMINDERS • MAKING A LATENT PRINT VISIBLE • Place some powder in lid, not too much, circular sweeping motion, just grazing surface
REMINDERS • LIFTING A LATENT PRINT ONTO A FINGERPRINT CARD Fingerprint card glossy side Don’t forget info on other side!
SOURCES • • Criminalistics/ Chapter 14 / Saferstein http: //www. fbi. gov/hq/lab/org/lpu. htm http: //www. onin. com/fp/ Kendall FG, Rehn BW. 1983. Rapid Method of Super Glue® Fuming Application for the Development of Latent Fingerprints. Journal of Forensic Science. 28(3) 777 -780. • Lewis, LA. et al. 2001. Processes involved in the development of latent fingerprints using the cyanoacrylate fuming method. Journal of Forensic Science. 46(2): 241 -246 • California Dept. Justice/ Physical Evidence bulletin-PEB 16 -17 • International Association of Identification – (IAI)-> http: //www. theiai. org