Understanding Fingerprints: Ridgeology & Matching Analysis

1. Dec. 6th & 8th, 2015 Unit 3 Fingerprints Take out your second packet and work on your to do list: Sticky Fingers Part 1 – Class Data from Modus Operandi Unit 3 Fingerprint Ridgeology - Notes Sticky Fingers Part 2 – Did the suspect rob the bakery? Fingerprint Challenge Part 2 Fingerprint Matching (1 triple, 6 doubles, 5 no matches) 3 Case Studies with questions Fingerprint Challenge Chapter 6: vocab., diagrams, notes, review, etc. Forensic Science Objectives: Students will be able to identify matching minutia in a suspects fingerprints and match them with prints found at a crime scene.

2. The Science of Ridges A Closer Look at Fingerprints Forensic Science T. Trimpe 2007 http://sciencespot.net/ Image from ftp://sequoyah.nist.gov/pub/nist_internal_reports/ir_6534.pdf

3. As we have learned in our first lesson, a fingerprint is made of a series of ridges and valleys on the surface of the finger. The uniqueness of a fingerprint can be determined by the pattern of ridges and valleys as well as the minutiae points, which are points where the ridge structure changes. The koala is one of the few mammals (other than primates) that has fingerprints. In fact, koala fingerprints are remarkably similar to human fingerprints; even with an electron microscope, it can be quite difficult to distinguish between the two. Did you know? Ridgeology: The study of the uniqueness of friction ridge structures and their use for personal identification.1 1Introduction to Basic Ridgeology by David Ashbaugh, May 1999 Image from http://www.cs.usyd.edu.au/~irena/minutia.gif

4. Fingerprint Identification When minutiae on two different prints match, these are called points of similarity or points of identification. At this point there is no international standard for the number of points of identification required for a match between two fingerprints. However, the United Kingdom requires a minimum sixteen points while Australia requires twelve.

5. Automated Fingerprint Identification System (AFIS) AFIS is a computerized system capable of reading, classifying, matching, and storing fingerprints for criminal justice agencies.  Quality latent fingerprints are entered into the AFIS for a search for possible matches against the state maintained databases for fingerprint records to help establish the identity of unknown deceased persons or suspects in a criminal case.

6. Ridge Characteristics Use these characteristics as points of identification when comparing fingerprint samples. The more points you can find in common, the better the match!

7. Crossover Core Bifurcation (fork) Ridge ending Scar Island Delta Pore Ridge Characteristics EXAMPLE http://cnx.org/content/m12574/latest/properties.jpg

8. http://www.dkfz.de/tbi/projects/bmcv/images/iu_it246_04s_fingerprint1.jpghttp://www.dkfz.de/tbi/projects/bmcv/images/iu_it246_04s_fingerprint1.jpg How many ridge characteristics can you identify in this fingerprint?

9. Now Go Back to “Sticky Fingers” • Work on Part 2 and see if you can match the suspect’s prints to those found at the bakery • First: Label the class (loop, whorl, or arch) for each print from the crime scene, then the suspect • You must show (point out and label) 4 matching minutia points for each matching print

10. April 10, 2013 Unit 3 Fingerprints Take out your second packet and turn to the Science of Ridges Sticky Fingers Part 2 - complete matching of the crime scene with the suspects fingerprints & answer questions 1-4 Continue working in your packet on Fingerprint Challenge and Matching FPs If time continue with Case Study 2: Thomas Jennings Forensic Science Objectives: Students will be able to identify matching minutia in a suspects fingerprints and match them with prints found at a crime scene.

11. Now Try the Fingerprint Challenge Note: • You are required to show at least 3 common features between prints in order to earn credit for a match. • Get a highlighter and hand lens to help mark common features and # or label the highlighted portions in some way.

12. April 11, 2013 Unit 3 Fingerprints Take out your second packet and turn to the Questions Part 2 Sticky Fingers Continue working in your packet on Fingerprint Challenge and Matching FPs Finish Case Studies and Questions Packet 2 Due tomorrow Forensic Science Objectives: Students will be able to identify matching minutia in a suspects fingerprints and match them with prints found at a crime scene.

13. April 12, 2013 Unit 3 Fingerprints Take out your second packet and turn to the Questions Part 2 Sticky Fingers Continue working in your packet on Fingerprint Challenge and Matching FPs Finish Case Studies and Questions Packet 2 Due Today Work on Terminoloy puzzle Forensic Science Objectives: Students will be able to identify matching minutia in a suspects fingerprints and match them with prints found at a crime scene.

14. April 22, 2013 Unit 3 Fingerprints Web Activity – Resume Study of Fingerprints and Fingerprint evidence Continue working in your 1st packet on Chapter 6 Fingerprint vocabulary, tables, and case studies from the text. Forensic Science Objectives: Students will be able to identify matching minutia in a suspects fingerprints and match them with prints found at a crime scene.

15. Dec. 8th & 9th, 2015 Unit 3 Fingerprints Take out your second packet and work on your to do list: Finish Sticky Fingers Part 2 – Did the suspect rob the bakery? Fingerprint Challenge Part 2 Fingerprint Matching (1 triple, 6 doubles, 5 no matches) 3 Case Studies with questions Fingerprint Challenge Chapter 6: vocab., diagrams, notes, review, etc. At 9:45 small quiz Forensic Science Objectives: Students will be able to identify matching minutia in a suspects fingerprints and match them with prints found at a crime scene.

17. Try It! 1 – Blow up your balloon about halfway and twist the end to keep the air from coming out. Do not tie it off! 2 – Use an ink pad to make a print with all of your fingers and label each one with a permanent marker. Write your name on the balloon as well. 3 – Blow up the balloon to full size and tie the end. 4 – Analyze the fingerprints to find several ridge structures that we have discussed. Use a highlighter to mark these structures on your “My Prints” worksheet. Think About It! Which ridge structures were most common in your fingerprints? Which ridge structures were most common in your group? Were there any structures that were not found in any of the fingerprints? Balloon Fingerprint Activity: http://www.msichicago.org/fileadmin/Education/learninglabs/lab_downloads/fingerprint_analysis.pdf