Thursday October 3rd, 2016 Announcements Agenda Making a Murderer Questions due Monday November 7th I won’t be here Friday, you will be completing a Fingerprint worksheet Agenda Start fingerprint notes Grab a notetaker if you havent yer Find Your Fingerprint Activity “Success is liking yourself, liking what you do and liking how you do it” – Maya Angelou Happy National Sandwich Day- it’s buy a sub get a free sub at subway Fun Fact: Every year more people die from taking selfies than from shark attacks

Chapter 5: Fingerprints

Historical Development Oldest known document showing fingerprints dates from the third century B.C. In ancient China finger and palm prints were used to authenticate legal documents. In western culture (Europe, Americas) 1684: Dr. Nehemiah wrote the first paper describing the patterns he saw on human hands 1823: Jan Evangelist Puekyn described nine distinct fingerprint patterns, including loops, spirals, circles, and double whorls

Historical Development In western culture continued 1883: Alphonse Bertillon created a system to use fingerprints to identify criminals; Bertillonage 1888: Galton and Sir E.R. Henry developed the classification system for fingerprints that is still used today in the US and Europe. 1896: Henry created a system that divided fingerprint records into groups based on whether they have an arch, whorl, or loop pattern Ten Card: Developed by Henry, contains all 10 fingerprints and marked with individual characteristics

What Are Fingerprints Fingerprints: raised portions of the skin, arranged in connected units called friction ridges. When pressed against things the ridges leave an impression (your fingerprint) Fingerprints are a result of oil and secretions from skin mixing with dirt Fingerprints on your right and left hands are not identical Fingerprints help with gripping objects Fingerprint patterns are formed at the 10th week of pregnancy

Check for Understanding 1 When do fingerprint patterns develop? First described 9 distinct fingerprint patterns? Who came up with Bertillonage and what was it? Contains all 10 fingerprints and marked with individual characteristics How far back do the first fingerprint documents go Who developed the current fingerprinting classification system we still use today

Characteristics of Fingerprints Fingerprint characteristics are named for their general appearance and patterns Loops: 65% of the total population Enter from either the right or left and exit from the same side they enter Have 1 delta (triangle) Whorls: 30% of the total population Look like a bull’s-eye, 2 deltas Arches: 5% of the total population Ridges that enter from one side of the fingerprint and leave from the other side with a rise in the center DON’T HAVE DELTAS

Characteristics of Fingerprints Two things forensic examiners look for on a fingerprint are the presence of a core and a delta Core: center of a loop or a whorl Delta: Triangular region located near the loop A ridge count is another characteristic used to distinguish fingerprints from each other To take a ridge count; an imaginary line is drawn from the center of the core to the edge of the delta

Characteristics of Fingerprints Basic Fingerprints can be divided further Whorl Patterns Plain Whorl (24%): has one or more ridges that make a complete spiral Central Pocket Loop Whorl (2%): has one or more ridges that make a complete circle Double Loop Whorl (4%): 2 separate loop formations and 2 deltas Accidental Whorl (2%): has 2 or more deltas and is a combination of 2 other patterns

Characteristics of Fingerprints

Characteristics of Fingerprints Basic Fingerprints can be divided further Arch Patterns Plain Arch(4%): ridges enter from one side, rise in the center and exit out the other side Has no characteristics of the loop pattern Tented Arch(1%): forms an angle

Characteristics of Fingerprints Minutiae: unique ridge patterns which causes everyone to have a unique fingerprint Fingerprint Identification: recognizing details in the differences between ridges, the number of ridges and their location on a specific fingerprint There are about 150 individual ridge characteristics on an average fingerprint

Check for Understanding 2 Exit from the same side they enter, and have 1 delta What is fingerprint identification 4 types of whorl patterns The triangular region of the fingerprint located near the loop The arch pattern can be further divided into Ridges enter from one side of the fingerprint and exit out the other side with a rise in the middle Unique ridge patterns which cause us to have unique fingerprints

Types of Fingerprints Three types of fingerprints found by investigators at a crime scene Patent Fingerprints: Visible prints, easy to find Left on a smooth surface when blood, ink or another liquid comes in contact with the hands and is transferred to the surface Plastic Fingerprints: indentations left in soft material (clay, putty or wax) Latent Fingerprints: Hidden prints Caused by the transfer of oils and other body secretions onto a surface Can be made visible by dusting with powders or chemicals

Patent Fingerprint Plastic Fingerprint Latent Fingerprint

Types of Fingerprints Fingerprints are taken by rolling each of the 10 fingers in ink and then rolling them onto a ten card

Frequently Asked Fingerprint Forensic Questions Can Fingerprints Be Altered or Destroyed You can not fully destroy your fingerprints but it is possible to alter them Vertical cut or slice: modifies the fingerprint by scarring or distorting Cut down the middle of the fingertip; pull the skin in different directions to generate an unusual fingerprint pattern when the skin heals Z-pattern: scar and distort the natural fingerprint into an unnatural pattern Burning: can be done by heat or chemicals Intent is to scar or obliterate the fingerprint Fingerprint examiners can use other areas of the finger to establish identity The FBI arrested and jailed Oregon lawyer Brandon Mayfield based on fingerprint evidence that linked him to the 2004 Madrid train bombing which killed 170 people. Mayfield had not traveled out of the united states in 10 years and claimed the fingerprint wasn’t a good match. Mayfield was held in custody for 2 weeks until Spanish authorities informed the FBI that the fingerprint was of an allgerian citizen.

Frequently Asked Fingerprint Forensic Questions Can Fingerprints Be Altered or Destroyed The FBI arrested and jailed Oregon lawyer Brandon Mayfield based on fingerprint evidence that linked him to the 2004 Madrid train bombing which killed 170 people. Mayfield had not traveled out of the united states in 10 years and claimed the fingerprint wasn’t a good match. Mayfield was held in custody for 2 weeks until Spanish authorities informed the FBI that the fingerprint was of an allgerian citizen. Vertical Cut or Slice Z-Pattern Cut Burn Method

Frequently Asked Fingerprint Forensic Questions How Reliable is Fingerprinting as a Means of Identification Humans are responsible for imputing and analyzing the information; humans make mistakes In 1995 156 fingerprint examiners were given a test; 1 in 5 examiners made at least 1 false identification The FBI arrested and jailed Oregon lawyer Brandon Mayfield based on fingerprint evidence that linked him to the 2004 Madrid train bombing which killed 170 people. Mayfield had not traveled out of the united states in 10 years and claimed the fingerprint wasn’t a good match. Mayfield was held in custody for 2 weeks until Spanish authorities informed the FBI that the fingerprint was of an Algerian citizen. The FBI arrested and jailed Oregon lawyer Brandon Mayfield based on fingerprint evidence that linked him to the 2004 Madrid train bombing which killed 170 people. Mayfield had not traveled out of the united states in 10 years and claimed the fingerprint wasn’t a good match. Mayfield was held in custody for 2 weeks until Spanish authorities informed the FBI that the fingerprint was of an allgerian citizen.

Frequently Asked Fingerprint Forensic Questions How Are Fingerprints Analyzed In 1987 the FBI had 23 million criminal fingerprint cards on file, finding a match for one found at a crime scene required manual searching and could take months In 1999 FBI developed IAFIS or AFIS (Integrated Automated Fingerprint Identification System) Provides digital, automated fingerprint searches, latent searches, electronic storage of fingerprint photo files and electronic exchange of fingerprints and test results Maintains the Criminal Master File: contains the fingerprints and criminal histories of 47 million people The FBI arrested and jailed Oregon lawyer Brandon Mayfield based on fingerprint evidence that linked him to the 2004 Madrid train bombing which killed 170 people. Mayfield had not traveled out of the united states in 10 years and claimed the fingerprint wasn’t a good match. Mayfield was held in custody for 2 weeks until Spanish authorities informed the FBI that the fingerprint was of an allgerian citizen.

Frequently Asked Fingerprint Forensic Questions How Are Latent Fingerprints Collected Dusting surfaces with a carbon powder make the fingerprint visible Photos of the fingerprint are taken before the fingerprint is lifted Tape is then used to lift the fingerprint and preserve the fingerprint Tape with the fingerprint is placed on an evidence card with the time, date, location and collector of the print Fingerprints from a non-smooth, hard surface requires the use of different chemicals Fingerprint residue combines with the chemicals making the fingerprint visible Chemicals on the next slide

Chemical Uses Application Safety Chemical Reaction Latent Print Ninhydrin Paper Object dipped or sprayed with Ninhydrin; must wait 24 hrs Do not inhale or get on your skin Reacts with amino acids found in sweat Purple-Blue print Cyanoacrylate Vapor Household items: plastic, metal, glass, and skin Heat sample in a vapor tent Do not inhale or get on your skin: irritant to mucous membranes Reacts with amino acids White print Silver Nitrate Wood Styrofoam Object dipped or sprayed with Silver Nitrate Wear gloves and avoid contact with skin Chloride from salt in sweat on the print combines with silver nitrate to form silver chloride Black or red-ish brown pigment under a UV light Iodine Fuming Cardboard Unpainted surfaces In a vapor tent, heat solid iodine crystals Toxic to inhale or ingest Iodine combines with carbohydrates in the latent print Brownish print (fades quickly must be photographed or sprayed with a starch solution)

Check for Understanding 3 Chemical to use when lifting a fingerprint off wood Prints left in soft material Cut which is done in an unusual pattern in order to distort the fingerprint Prints which are hard to see How would you lift a print using Cyanoacrylate Vapor Using this chemical leaves behind a blue-purple print Prints which are easy to see