Raman Spectroscopy and Chemometrics for Forensic Bloodstain Analysis: Species Differentiation, Donor Age Estimation, and Dating of Bloodstains

• NCJ Number: 309937
• Author(s): Kyle C. Doty
• Date Published: 2017
• Length: 197 pages
• Grant Number(s): 2015-R2-CX-0021
• Agencies: NIJ-Sponsored
• Publication Type: Thesis/Dissertation; Research (Applied/Empirical)

Annotation

This study examines the use of Raman spectroscopy and chemometrics for forensic bloodstain analysis, particularly species differentiation, donor age estimation, and dating of bloodstains.

Abstract

This study uses Raman spectroscopy to determine the time since deposition (TSD) and chronological age of a donor for bloodstains, as well as to differentiate human blood from animal blood and from potential false positive materials. Research using Raman spectroscopy for these four topics is somewhat limited, and that which does exist needs significant improvements. Among these improvements is the incorporation of statistically reliable results, as was called for in the 2009 National Academy of Sciences report, which stated that many areas of forensic science do not live up to the necessary standards. The methodologies developed herein will not only provide immediate and lasting improvements to the theory and practice of forensic bloodstain analysis as related to criminal justice, but also advance the field of forensic science to demonstrate the importance and versatility of Raman spectroscopy as a meaningful analytical technique. The field of forensic science is constantly growing, so the advancement of old and unreliable techniques is at the forefront of what will lead to future progress and improvement. Current methods for identification and analysis of bloodstains are underwhelming due to the insignificant amount of information provided in a destructive, unreliable, and unsafe manner. As is the purpose of this research, creating new methodologies that are rapid, nondestructive, robust, statistically reliable and safe would significantly advance the way bloodstains are currently analyzed, while providing more useful and relevant information for investigations and criminal proceedings. Raman spectroscopy, along with advanced statistical analysis, has been used to analyze bloodstains in an effort to obtain forensically important and probative information.