Evidence analysis and processing

THC isomers, also known as THC analogs or semi-synthetic cannabinoids, are structurally related to Δ9-tetrahydrocannabinol (Δ9-THC) and have similar toxicity and impairing effects. A recent study indicated that Δ8-THC use was around 27% of marijuana use, based on detection and ratios of cannabinoid metabolites in workplace drug testing. Other analogs of interest include hexahydrocannabinol (HHC) and THC-O. THC isomers are generally perceived as legal and are also seen in states with legal marijuana.

The pubic symphysis joint on the pubic bone is frequently used in anthropology to estimate age-at-death in late adolescent and adult individuals. This webinar will provide a background on the age indicator, as well as a review of the anatomical features used in the age estimation methods based on this joint. The primary focus of the webinar is to help participants better interpret the written phase descriptions in pubic symphysis age estimation methods.

This webinar was hosted by the NIJ Forensic Technology Center of Excellence on January 11, 2023.

Forensic anthropologists face the challenge of sorting remains from commingled assemblages. This webinar examines how chemical signatures of bone can complement physical reassociation strategies. Laser-induced breakdown spectroscopy (LIBS) offers rapid, visually non-destructive analysis that acquires chemical information from bone. Statistical evaluation of chemical profiles taken across 1284 bones from 45 individuals reveals that physicochemical variation exists between individuals and, consequently, can be used to classify the bones.

The Transition Analysis 3 (TA3) age-at-death estimation method was developed as part of an international research project supported by National Institute of Justice (NIJ) award #2014-DN-BX-K007. This presentation provides a brief history of the TA3 project from its beginnings in the late 1990s to its current status two decades later. Participants learn about the iterative process used to identify traits and develop definitions and are introduced to the TA3 trait manual and generic data collection form.

This webinar will explore the prevalence of strangulation in sexual assault cases, including considerations for evidence collection and supporting victims. This webinar was hosted by the NIJ Forensic Technology Center of Excellence on April 14, 20222

This presentation briefly discusses the current state of skeletal sex estimation in forensic anthropology. The primary focus of this presentation is on the MorphoPASSE: Morphological Pelvis and Skull Sex Estimation database and program for skeletal sex estimation. The presentation details the revised trait descriptions and scoring procedures, with examples, and demonstrates how to use the MorphoPASSE graphical user interface and interpret the output.

The National Institute of Justice’s Terrestrial LiDAR Scanning (TLS) Working Group was convened to create consensus-based best practices that standardize and improve the use of TLS in criminal justice applications. This webinar is intended to serve as a general overview of the technology, its use in scene documentation and reconstruction, and key takeaways of the resulting best practice guidelines.

This webinar was hosted by the Forensic Technology Center of Excellence on  May 3, 2022.

With the rise of illicit fentanyl, fentanyl analogues, synthetic cathinones, xylazine, and other substances adulterating many traditional street drugs, users often have no idea what they are consuming, leading to overdose and death.  This further complicates toxicology testing and death determination.  This presentation will cover interesting postmortem case studies from Ohio, Denver, and Miami from the scene perspective through autopsy and toxicology testing.

Scientists from three participating laboratories - University of Central Florida (UCF), Center for Forensic Science Research and Education (CFSRE), and InnoGenomics (IGT) - presented results obtained from mock sexual assault samples using the SpermX method and their in-house differential extraction method. All three laboratories processed identical sets of female:male mixture swabs at various ratios in triplicate and presented their experiences and insights from this study.

The Forensic Technology Center of Excellence recently published a collection of five articles as a Special Issue in Forensic Science International (FSI): Synergy. These articles are known collectively as the Human Factors in Forensic Science Practice Sourcebook.  The sourcebook is intended to educate forensic science practitioners and managers on the ways human factors can impact forensic science practice both positively and negatively and to expand the discussion beyond issues of bias.

Hair evidence collected as part of a forensic investigation has the potential to provide valuable source information through DNA analysis of its root. This webinar discusses the process of utilizing Hematoxylin staining in forensic casework as an indicator of hair root DNA suitability. The presenters demonstrate the process of staining hair roots with Hematoxylin, as well as provide visual examples of stained hair roots.

Fractography is a tool for studying material failure. Analysis of cracks and fractures can reveal information about how, why, and where a fracture initiated and how a crack traveled, providing insight into the cause of failure. This webinar provides a basic introduction to forensic fractography of bone, which represents a new model for skeletal trauma that emphasizes understanding the cause of material failure rather than simply classifying fracture patterns.

This webinar was hosted by the NIJ Forensic Technology Center of Excellence on November 2, 2022.

This webinar will review the features and advantages of the Idaho State Police Forensic Services’ freely available sexual assault kit evidence tracking system.

This webinar was hosted by the NIJ Forensic Technology Center of Excellence on April 7, 2022.

This webinar is designed to provide a peek behind the curtain of cosmetics, specifically those applied to the face. The presenter will provide an overview of common cosmetic ingredients, including the typical usage levels and their purpose in these products. The presenter will also discuss various analytical approaches and limitations to the analysis of cosmetic products and their individual components.

This webinar was hosted by the NIJ Forensic Technology Center of Excellence on February 17, 2022. 

The FBI Laboratory conducted a comprehensive study known as the National Footwear Database Evaluation. The purpose of the study was to determine the feasibility of developing and implementing a national footwear database system to generate criminal intelligence for law enforcement and serve as a tool for forensic science researchers. This webinar will highlight the team's findings, conclusions, and recommendations. T

his webinar was hosted by the NIJ Forensic Technology Center of Excellence on February 15, 2022.

The widespread use of handheld smartphones and other devices capable of recording audio and video means that user generated recordings (UGRs) are increasingly presented as evidence in criminal investigations. Combined with other recordings from law enforcement systems, home surveillance systems, etc., the availability of UGRs may offer important audio forensic insights. Forensic handling of UGRs requires best practices for assessing authenticity and integrity of the recorded information.

This webinar describes a simple and systematic method for comparing fracture fits using standardized qualitative and quantitative criteria. An extensive database of nearly 9,000 samples of duct tapes, automotive polymers, and textiles is used to estimate performance rates and strengthen the scientific foundations of fracture fit determinations. Also, the consistency of results from inter-laboratory studies shows the utility and reliability of the proposed approach.