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Full-Text Articles in Evidence

Optimizing Collection Of Trace Biological Samples From Vehicle Headrests, Kevin Tang, Jesse Ramirez, John Bond, Jocelyn Weart, Yvette Delatorre, Ian Fitch, Steven Lee May 2017

Optimizing Collection Of Trace Biological Samples From Vehicle Headrests, Kevin Tang, Jesse Ramirez, John Bond, Jocelyn Weart, Yvette Delatorre, Ian Fitch, Steven Lee

Themis: Research Journal of Justice Studies and Forensic Science

Tape-lifting and swabbing are two methods commonly used for collecting biological samples in the United Kingdom and United States to investigate vehicle crimes. Determining the optimal collection method may lead to an increase in generating DNA profiles and crime-solving. The objective of this study is to evaluate the efficiency of adhesive tape and the double-swab collection methods for investigating vehicle crimes with possible touch DNA samples. Two experiments were conducted to evaluate the use of tape-lifts and swabs on spiked common vehicle fabric materials. The efficiency of recovery between the two collection methods was performed using qPCR. The results from ...


Forensics’ Fight: A Need For Aggressive Strategies Against Confirmation Bias, Madison Mcgowan May 2017

Forensics’ Fight: A Need For Aggressive Strategies Against Confirmation Bias, Madison Mcgowan

Themis: Research Journal of Justice Studies and Forensic Science

In 2009, the National Academy of Sciences produced a lengthy report illuminating significant weaknesses present within the forensic community. One complex fault found in forensics was conformation bias. Since it is within human nature to make decisions based on contextual information, assumptions, and pre-held opinions, confirmation bias is an issue that will continue to persist. Therefore, stronger efforts must be made to recognize and abate the problem of bias within the field of forensics in order to preserve the notion that forensic science exists to serve principles of both truth and justice. Accordingly, this paper argues for the fight against ...


Physical Match: Unique Fracture Patterns In Wooden Popsicle Sticks, Yiu Ming Sunny Lau May 2017

Physical Match: Unique Fracture Patterns In Wooden Popsicle Sticks, Yiu Ming Sunny Lau

Themis: Research Journal of Justice Studies and Forensic Science

Physical match (or physical fit) evidence was considered reliable in court for years, until the Daubert case, which required standardized scientific methodology on all forensic evidence. Physical matching faces the same criticism as other forms of physical evidence (specifically, that it lacks a scientific foundation). Physical matching is based on the idea that when an object is fractured, the shape of each fragment is unique and it is not possible to recreate a fragment that is identical to any other. In this study, fifty wooden popsicle sticks were broken in half, the pieces were mixed, and then reconstructed using physical ...


Minimum Education Requirements For Crime Scene Investigators, Araseli Saldivar May 2017

Minimum Education Requirements For Crime Scene Investigators, Araseli Saldivar

Themis: Research Journal of Justice Studies and Forensic Science

The initial crime scene investigation is critical since it is the primary step in the investigative process; therefore, individuals assigned to process a scene should be highly educated. Improperly educated (or uneducated) crime scene investigators (CSIs) can mishandle evidence during an investigation, affecting the outcome of cases. The minimum education requirement for CSIs should transition from a high school diploma—the current requirement—toward a bachelor’s degree. The importance of acquiring a college-level education is observed in a study conducted on crime scene examiners in Australia. To determine the educational requirement for CSIs in the United States, information was ...


Neuroscience In Forensic Contexts: Ethical Concerns, Stephen J. Morse Feb 2017

Neuroscience In Forensic Contexts: Ethical Concerns, Stephen J. Morse

Faculty Scholarship at Penn Law

This is a chapter in a volume, Ethics Challenges in Forensic Psychiatry and Psychology Practice, edited by Ezra E. H. Griffith, M.D. and to be published by Columbia University Press. The chapter addresses whether the use of new neuroscience techniques, especially non-invasive functional magnetic resonance imaging (fMRI) and the data from studies employing them raise new ethical issues for forensic psychiatrists and psychologists. The implicit thesis throughout is that if the legal questions, the limits of the new techniques and the relevance of neuroscience to law are properly understood, no new ethical issues are raised. A major ethical lapse ...


Approximate Bayesian Computation In Forensic Science, Jessie H. Hendricks Jan 2017

Approximate Bayesian Computation In Forensic Science, Jessie H. Hendricks

The Journal of Undergraduate Research

Forensic evidence is often an important factor in criminal investigations. Analyzing evidence in an objective way involves the use of statistics. However, many evidence types (i.e., glass fragments, fingerprints, shoe impressions) are very complex. This makes the use of statistical methods, such as model selection in Bayesian inference, extremely difficult.

Approximate Bayesian Computation is an algorithmic method in Bayesian analysis that can be used for model selection. It is especially useful because it can be used to assign a Bayes Factor without the need to directly evaluate the exact likelihood function - a difficult task for complex data. Several criticisms ...