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Forensic sciences

Cannabinoid Conundrums Webinar Series Expert Panel

August 2023

As evident by the Cannabinoid Connundrums webinar series, the rapidly changing world of cannabinoids offers many conundrums. To tackle some of these questions, Dr. Ruth Winecker led a panel discussion with Dr. Ed Cone, Dr. Nathalie Desrosiers, Mr. Justin Poklis, and Mr. Nelson Santos. This diverse slate of thought leaders includes experts in analytical chemistry, forensic toxicology, clinical research, and drug chemistry. This webinar was hosted by the NIJ Forensic Technology Center of Excellence on August 3, 2023. 

Cannabinoid Pharmacology: Three Decades of Controlled Human Cannabinoid

August 2023

Controlled drug administration studies are valuable tools for acquiring a detailed understanding of the pharmacodynamic and pharmacokinetic profiles of cannabinoids. ∆9-tetrahydrocannabinoid (THC) is the primary psychoactive cannabinoid in cannabis with the potential to negatively impact cognitive and psychomotor performance and workplace safety. These studies establish behavioral and subjective effect profiles while simultaneously collecting pharmacokinetics data.

Bridging Generational Gaps in the Laboratory

March 2023

This webinar addresses a common cross-cultural issue experienced every day in the crime laboratory and within the greater criminal justice community, the generation gap. Simply defined as the different outlooks or opinions between individuals of different generations, this complex topic can create division within a workforce or, if understood, can elevate personnel to achieve organizational goals.

All Is Not Pot That’s Green: An Overview of THC Isomers

June 2023

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.

Age Estimation from the Pubic Symphysis: Back to Basics

January 2023

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.

Advances in Chemical Sorting of Commingled Remains Compressed

November 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.

Using Risk Management to Optimize Forensic Laboratory Operations

June 2022

The use of risk management has been historically absent from the management of forensic science laboratories. While ISO 31000 (Risk Management Principles and Guidelines) and ISO 9001 (Quality Management System) emphasized risk management, it was not until ISO/IEC 17025: 2017 highlighted its importance that forensic science managers began to take note. Even since its inclusion in ISO/IEC 17025, there remains a misunderstanding on what risk management is and how it can be used to improve laboratory operations.

Trauma Informed Investigations for Sexual Assault Cases

April 2022

This webinar will highlight the importance of conducting a victim-centered, trauma-informed investigative interview for sexual assault cases. Trauma-informed investigative interviews lay the foundation for improved victim engagement with the criminal justice system and increased ability to resolve sexual assault cases.

This webinar was hosted by the NIJ Forensic Technology Center of Excellence on April 26, 2022

Transition Analysis 3 Age at Death Estimation: Past, Present, and Future

December 2022

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.

Skeletal Sex Estimation and Practitioner Use of MorphoPASSE final

October 2022

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.

Intro and Basics of Statistics for Forensic Toxicology

May 2024

This session provides an overview of the fundamental principles of statistics as encountered and applied in forensic toxicology. Various elements of statistics are often utilized or relied upon by scientists to describe produced results and to demonstrate if forensic instruments or processes are “working” or “in-control”. Here we establish the basic terminology for the principles of statistical analysis. Participants will begin to be better equipped to interpret and analyze forensic toxicology data accurately and effectively. 

Let’s Talk About Stats

July 2024

In this fireside chat, session six of the the Foundational Statistics for Forensic Toxicology series, panelists include practitioners and experts in forensic toxicology, and subject matter experts for the application of statistics in forensic toxicology. Join us in a dynamic and engaging session to explore common frustrations and challenges experienced in the laboratory, providing participants with valuable insights and practical solutions.

Calculation of Type A Data from Control Data for Measurement Uncertainty

July 2024

Session five of the Foundational Statistics for Forensic Toxicology series will incorporate concepts from earlier sessions and focus on the practical application of control data in estimating Measurement Uncertainty (MU). Rather than a discussion about how to calculate the MU, this session provides practical examples to demonstrate the key elements of the statistical process. Participants will learn how to incorporate control data into MU estimation by leveraging statistical techniques aimed at quantifying the uncertainty associated with measurement processes.

Distributions & Standard Deviation

May 2024

This second session in the  Foundational Statistics for Forensic Toxicology series explores various distributions commonly encountered in forensic toxicology (normal, rectangular, etc.). Participants will learn about the characteristics of these distributions and how they manifest in toxicological data. Also, this session covers statistical measures that can describe and compare distributions, including variance, standard deviation, and relative standard deviation.

Statistical Tests and Hypothesis Testing

May 2024

This third session of the Foundational Statistics for Forensic Toxicology series explores hypothesis testing, a fundamental concept in statistical analysis, and its applications in forensic toxicology. Participants will gain an understanding of the different types of statistical tests, their respective applications, and how they can be utilized to uncover meaningful insights from toxicological data. 

Use of Controls and Other Control Chart Elements

June 2024

In this fourth session of the Foundational Statistics for Forensic Toxicology series, we address common challenges, misconceptions, and questions encountered in day-to-day forensic toxicology laboratory settings related to statistics. Participants will gain insights into the practical application of statistical concepts and terminology in quality control and control charting, including trends and outliers. Furthermore, participants will learn about data interpretation, distinguishing between results that occur due to statistical significance and those the occur due to random variation.

Foundational Statistics for Forensic Toxicology

This six-part webinar series provides a fundamental knowledge base in statistics before advancing into more complex concepts. This series aims to address common questions that arise in forensic toxicology and to increase both the attendees’ confidence of what they know and the awareness of what they have yet to learn. Commonly encountered data types and both descriptive and inferential statistics will be defined and discussed...

Terrestrial LiDAR Scanners: Guidelines for Use in Criminal Justice Applications

May 2022

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.

Things Are Not What They Seem A Collection of Interesting Case Studies

May 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.

Interlaboratory Comparison of SpermX and Conventional Differential Extractions

August 2022

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.

Human Factors in Forensic Science Practice

June 2022

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 Root Staining – What Can Hematoxylin Do for Your Laboratory?

August 2022

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.

Forensic Fractography of Bone A New Model for Skeletal Trauma Analysis

November 2022

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.