Forensic Science and Technology Commons^™

Quality Management And Oversight Of Texas Forensic Science Service Providers, Sarah P. Chu

Dissertations, Theses, and Capstone Projects

Forensic science oversight in the U.S. largely relies upon voluntary third-party forensic laboratory accreditation programs. Without a national system of regulation and given the highly fragmented local systems of control, few forensic science service providers (FSSPs) are subject to regulatory oversight beyond their third-party accreditors. Texas is unique in its establishment of a robust statewide oversight system and a strong governmental culture of transparency, permitting this study of forensic quality management. This study consisted of two parts. The first part of this dissertation characterized and analyzed quality incident reports (QIRs) published by the Texas Department of Public Safety Crime Laboratory …

Scientific Development Of An Integrated Workflow For Latent Print, Questioned Document, And Dna Processing Of Paper Evidence, Ashley Morgan

Dissertations, Theses, and Capstone Projects

Touch paper evidence could be the source of probative human DNA but recovery is challenging and forensic laboratories instead prioritize processing by the Latent Print and Questioned Document disciplines. Recent advances in DNA collection methods and the increased sensitivity of STR typing kits have improved success rates for DNA testing of paper evidence; but prior to implementing DNA collection, laboratories have to decide in which order to examine paper for the different types of forensic evidence. This thesis developed and tested a multi-discipline workflow for processing paper evidence by DNA, Latent Prints and Questioned Documents experts. Preliminary sampling studies indicated …

Evaluation Of The Potential Of Automated Sem-Eds Analysis For The Discrimination Of Inorganic Soil Particles, Anna S. Duggar

Dissertations, Theses, and Capstone Projects

Soil, that complex mixture of minerals, organic particles, chemicals, and anthropogenic materials, is ubiquitous and easily transferred, which gives it forensic relevance. Forensic soil analysis has traditionally included the identification and comparison of both organic and inorganic components, the inorganic portion being most commonly examined by light microscopy and other instrumental techniques. Predominantly, the inorganic materials in soil are naturally-occurring minerals, contributed as grains from the surrounding bedrock, which gives a soil its regional character. That parent material then undergoes physical, chemical, and anthropogenic changes producing wide geographic variation within a single region. This variation forms the basis for potential …

Forensic Analysis Of Fiber Dyes Via Surface-Enhanced Raman Spectroscopy, Mircea A. Comanescu

Dissertations, Theses, and Capstone Projects

Fibers are a common piece of evidence found at crime scenes that may become a link between the scene and a suspect, or allow for the reconstruction of certain crime events. Although a big portion of fibers are still white cottons, the advancement of commercial fiber production and dyeing in the past century led to an increase in types of synthetic fibers and dye applications that can be found and used in forensic analyses. Nonetheless, the fiber evidentiary value is not fully explored, as for the most part, the separation and analysis of the dye on the fiber is not …

The Advanced Spectroscopic Analysis Of Organic Gunshot Residue And Explosives, Jennifer M. Leonard

Dissertations, Theses, and Capstone Projects

With the prevalence of shooting cases and terrorist attacks/or threats that plague the current state of the criminal justice system, it is of paramount importance to be able to detect, identify and interpret the presence of gunshot residue or explosives material. This concern is seen in law enforcement agencies and the media throughout the United States and abroad.

Currently, the typical method of analyzing gunshot residue in most crime laboratories serves to identify the inorganic constituents of the primer residue, namely lead, barium and antimony. However, it is possible that the organic matter from the propellant could provide different information …

Qualitative And Quantitative X-Ray Diffraction Analysis For Forensic Examination Of Duct Tapes, Rebecca E. Bucht

Dissertations, Theses, and Capstone Projects

Duct tapes are an increasingly important class of forensic evidence. This research has studied the value of using x-ray diffraction (XRD) to extend the ability of evidence examiners to gain additional information about a duct tape specimen.

Duct tapes are composed of five different layers. Starting from the non-adhesive side, these layers are the release coating, backing, scrim, primer and adhesive. The release coating assists in reducing unwind tension and preventing the tape from sticking to itself when on a roll. The backing layer serves as a support for the adhesive, and is usually based on polyethylene. The scrim is …