Semester

Spring

Date of Graduation

2010

Document Type

Thesis

Degree Type

MS

College

Eberly College of Arts and Sciences

Department

Forensic and Investigative Science

Committee Chair

Keith Morris

Committee Co-Chair

Patrick Buzzini

Abstract

Lip prints have been proposed as a type of impression evidence with similar issues as fingerprints, but with greater scrutiny by the forensic community due to a lack of history in using this type of impression as evidence. A survey of 11 questions about lip print examination was sent to 63 members of the Chesapeake Bay Division of the International Association for Identification (CBD-IAI) to gather opinions from active forensic scientists in determining an appropriate direction for this study. The responses were presented at the spring CBD-IAI 2009 conference to generate more discussion and to achieve greater awareness. A method including glass slides, magnetic black powder with photography and tape lifting resulted. Phase I focused on intervariability with the collection of 300 impressions from 100 individuals. Phase II focused on intravariability. The 49 "best" donors from Phase I were selected for the collection of 6 lip prints on 5 different dates throughout 2 different seasons, fall and winter. In total, 1770 lip prints were collected in this study. In addition to promoting awareness for lip prints, the purpose of this study was to test the reliability of AFIX Tracker, a minutiae based system, for lip print individualization. Reproducible rules of mark-up were established for lip prints based on the author's classification systems, frequency analyses, and experience with AFIX Tracker for fingerprint examination. Preliminary analysis resulted in the detection of 4 potentially useful "minutiae", or unique identifying characteristics: bifurcations, diamonds, triangles, and middle horizontals. Each minutiae Type was tested via AFIX Tracker by the analysis of 10 individuals from Phase I. Focus was placed on the number of matched minutiae and match score corresponding to where False Positives (Type I errors) decrease and where False Negatives (Type II errors) increase. As a preliminary study, it cannot be said if all individuals produced different lip prints. In addition, the author cannot say if changes did or did not occur in lip print patterns with change in time. Future analysis will involve a more thorough approach to these issues.

Download

Share

COinS