Evidence analysis and processing

The NIJ Forensic Science Research and Development Symposium is an open meeting where attendees can learn about NIJ-funded research across a variety of forensic science areas. 

This workshop explores the impact inconsistent drug analysis reporting has on public health and public trust. The value and implementation of the Global Uniform Analysis and Reporting of Drug-Related Substances (GUARDS) innovative methodology in over 200 instruments across United States Drug Enforcement Administration (DEA) laboratories are presented, as well as the efforts of other labs of the U.S. Customs and Border Protection (CBP) and Illinois State Police.

Of recent, forensic toxicology laboratories have been grappling with the emergence of tetrahydrocannabinol isomers within biological specimens. Traditional methodologies are often inadequate in the separation of Δ9-tetrahydrocannabinol and Δ8-tetrahydrocannabinol, which are the most common isomers identified in forensic testing.

Following a multi-month course of data collection using simulated human gravesites, Ground-Penetrating Radar (GPR) researcher Jordan Mullikin will discuss the advantages and disadvantages of GPR for the detection of unmarked graves. Additionally, this webinar will explore Light Detection and Ranging (LiDAR) technology for the same purpose and investigate the potential integration of both technologies for optimal detection of clandestine graves within the law enforcement and forensic communities.

Numerous crime laboratories have witnessed a surge in gun-related evidence submissions, leading to an increased demand for DNA testing and entry into the National Integrated Ballistic Information Network (NIBIN) for firearms-related investigations. Simultaneously, the forensic value of firearms analysis has substantially grown, owing to advancements in DNA technology and the expansion of the NIBIN database. Consequently, several forensic labs have established dedicated units specifically focused on comprehensive firearms analysis.

With the passage of the 2018 Agricultural Improvement Act (Farm Bill), forensic laboratories have been tasked with differentiating seized cannabis samples as either hemp or marijuana. The new legislation declassified hemp as a Schedule 1 drug substance and defined it as cannabis containing 0.3 % or less of decarboxylated-Δ9-THC (total Δ9-THC). The National Institute of Standards and Technology (NIST) has been working to help forensic laboratories with these challenging measurements through the development of extraction protocols and analytical methods.

Dr. Julie L. Valentine introduces the application of touch DNA in sexual assault cases through a case study. A literature review on touch DNA is summarized to provide contextual information and research on touch DNA analysis findings in groping sexual assault cases is discussed. The webinar concludes with recommendations for multidisciplinary partners to collect, submit, and analyze evidence in sexual assault cases for touch DNA.

This webinar was hosted by the NIJ Forensic Technology Center of Excellence on April 18, 2023.

Part I: GeoFOR is a free web-based collaborative forensic taphonomic application and database that utilizes geospatial technology and machine learning to deliver data-driven postmortem interval estimations to better facilitate identification and reconstruct events around the time of death. This presentation describes the geoFOR application and its potential for advancing the field of forensic science.  

While forensic DNA analysis can identify an individual(s) at a crime scene, it cannot identify the biological source from which that DNA was obtained – e.g. blood, saliva, or semen. Identification of the biological source of DNA can provide important contextual information for forensic investigations as well as evidence in court. Nearly all current methods used for body fluid identification are presumptive. Here we present a new proteomic mass spectrometry method for the confirmatory identification of blood, saliva, and semen.

It is well-known that bloodstain pattern analysis (BPA) on textiles is difficult and subject to many errors or misinterpretations. In this webinar, we probe the reason for this and suggest useful information that a bloodstain pattern analyst may be able to extract from the observed bloodstains. The data set demonstrates the roles of drop volume and impact speed in bloodstain formation on textiles.

This webinar was hosted by the NIJ Forensic Technology Center of Excellence on December 12, 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. 

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.