1 / 27

Presented by Robert Carpenter UCI Undergraduate Research Symposium May 14, 2005

Quality of Latent Prints. Presented by Robert Carpenter UCI Undergraduate Research Symposium May 14, 2005. Why Is This Important?. Example cases of fingerprint misidentification:

adriel
Télécharger la présentation

Presented by Robert Carpenter UCI Undergraduate Research Symposium May 14, 2005

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Quality of Latent Prints Presented by Robert Carpenter UCI Undergraduate Research Symposium May 14, 2005

  2. Why Is This Important? • Example cases of fingerprint misidentification: • After serving six years of a 35 year sentence for allegedly shooting a police officer in 1998, on January 23, 2004 a 33-year old (Stephan Cowan), was freed after prosecutors learned that a fingerprint used in his trial belonged to someone else. • After the fingerprint analysis of a detonator bag from the Madrid train bombings, the FBI announced, “The FBI lab stands by their conclusion of a 100 percent positive identification (of American lawyer Brandon Mayfield).” Within the month a federal court threw out the case against him. The FBI expressed regret for a fingerprint identification error that led to his arrest.

  3. Are These Isolated Incidents? • 158 people have been EXONERATED and released from prison after their cases have been proven by DNA to have been miscarriages of justice. www.InnocenceProject.org May 1, 2005 • Many of these people were released from death row. • How many inmates are imprisoned because of “mistakes” made during fingerprint identification?

  4. Research Questions • When examining the prints of a subject, how many points are lost in a latent print as opposed to the points in the rolled print? • Does the retraining of personnel increase the quality of processing for both rolled and latent prints?

  5. Hypothesis When evaluating the points of identification of a subject’s fingerprints, there will be fewer than half of the identification points in the latent print when compared to those found in the rolled print. Retraining personnel will increase the quality of processing both rolled and latent prints, creating more points of identification. H 1 H 2

  6. Historical Use Of Fingerprints As Identification • Belief that fingerprints are unique to each person dates back thousands of years. • They have been used for over a century to convict suspects. • They have been used as the ultimate, indisputable form of identification, without serious scrutiny of the process. • There has been a lack of standardized training.

  7. Latent PrintA fingerprint made by deposits of oils and/or perspiration, not usually visible to the human eye. Definitions Rolled Print When the pad of a finger is inked and rolled on a fingerprint card.

  8. Points Of Identification

  9. Methodology Research Site • Campus of the University of California, Irvine • Chosen for convenience • Researcher access • Availability of subjects • Financial considerations • Availability of the AFIX Tracker Software

  10. Fingerprint Matching Software • AFIX Tracker

  11. Population • Gender: Females 366, Males 157 • Participants in the subject pool were volunteers who receive class credit. • Consent forms were signed prior to the administration of fingerprint processing. • Subjects were briefed at the time of the experiment to ensure that all rules of ethical consideration were adhered to.

  12. Gender of Participants

  13. RA Procedures • Research Assistants were trained at the beginning of this research project. • They were trained in the techniques used by law enforcement in the collection of latent prints. • The methods of rolling fingerprints onto “ten-print” cards were also taught. • Retraining in these methods was conducted midway through the research project.

  14. The Processing Of Fingerprints

  15. Procedures • Subjects entered, read and signed consent forms and filled out demographic information. • Subjects were informed that their fingerprints would be protected in a locked university facility. • Subjects were asked to touch two different items. • Subjects then had fingerprints “rolled” at station 2. • Subjects’ fingerprints and consent forms were logged by student ID numbers.

  16. Measures • Number of rolled prints collected…5250 • Number of latent prints collected…1683 • Total number of prints processed…6933

  17. Measures (continued) • All rolled and latent prints were scanned into the computer utilizing the AFIX Tracker software. • All fingerprints were subjected to “auto-extraction” to identify points of identification. • Statistical analysis programs were utilized to answer all pertinent questions. • AFIX Tracker was used to run latent print searches against the rolled prints obtained from the subjects.

  18. Points Of Identification: Initial vs Retrained

  19. Change In Number Of Identifiable Points After Retraining (Rolled Prints) % Of Change Research Assistant Coded Identity

  20. Change In Number Of Identifiable Points After Retraining (Latent Prints) % Of Change Research Assistant Coded Identity

  21. Matching Prints With Certainty • Here are examples of accurate and inaccurate matches made by AFIX. 8 point match 11 point mismatch

  22. Outcome Of AFIX Searches • All latent prints were searched against the corresponding rolled prints from the same subjects. • 30% of the time AFIX was not able to match to any subject. • Of the “matches” made: • 60% of the matches were to the proper subject. • 40% of the time it matched to the WRONG subject. • These findings mirrored an earlier study. (Karrie Casada, 2004)

  23. Discussion • The use of Live Scan decreases the error rate among rolled prints. The technician can see the quality of print at the moment and re-roll as needed. • The increase of identifiable points of latent prints and the improved proficiency rating of the research assistants is most likely attributed to the retraining of the latent print processing techniques.

  24. Where Do We Go From Here? • The issue is: Can a fingerprint be linked to one and only one person? • Additional studies need to be conducted. • Standardized performance criteria for field officers/investigators who process latent fingerprints, as well as periodic retraining sessions. • “Blind” fingerprint examiners, not under the influence of the police department, should do the comparative analysis.

  25. Acknowledgements: • Thank you to those who made this research possible: • Professor Simon Cole Ph.D. • Professor Valerie Jenness Ph.D. • Rachel Dioso Ph.D. Candidate • Gerhard “Harry” Georgescu • UROP - Undergraduate Research Opportunities Program • The Phoenix Group, Inc. AFIX Tracker

  26. Acknowledgements: • The volume and quality of fingerprints collected would not have been possible without the following: • Research Assistants: Edward Auttapibarn Allyson Maddy Stacey Brown Neha Mahajan Danielle Campbell Scott Manese Farah Chaugule Chivan Ngo Ana-Maria Comsa Marina Ovanessian Joy deVera James (JB) Robinson Adam Dorn Geoff Ross Danielle Evans Jeremy Takahashi Ernest Hu Bunneat Thap Jazmin Ibarra Ngoc-Suong “Sophie” Vo Christine Lee Shanshan Yu Wally Liu Thank you all!

  27. For More Information: Contact Rob Carpenter Department of Criminology, Law & Society University of California, Irvine carpentr@uci.edu

More Related