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These data are part of NACJD's Fast Track Release and are distributed as they were received from the data depositor. The files have been zipped by NACJD for release, but not checked or processed except for the removal of direct identifiers. Users should refer to the accompanying readme file for a brief description of the files available with this collection and consult the investigator(s) if further information is needed.

The general and original hypothesis to be explored in this study was that multi-slice computed tomography (CT) imaging of decedents in whom elder abuse was suspected or reported might enhance the work of the medical examiner by providing novel information not readily available at conventional autopsy and/or by ruling out the need for complete conventional autopsy in cases in which abuse findings were negative, thereby providing: time and cost efficiencies, additional evidentiary support in the form of state-of-the-art images, and, in some cases, compassionate support for families whose religions or cultures required more rapid and/or noninvasive techniques.

No quantitative or qualitative data are available with this study. The data are comprised of the images taken from the autopsies of 57 decedents.

The overall goal of this project was to answer the question of how often non-identifiable fingermarks occur on naturally loaded handgun ammunition and what range of associative values can be expected. This is a potential new source of evidence, as current forensic science practices set these fingermarks aside, leaving them unexamined. The project was successful, with highly significant findings showing that non-identifiable fingermarks with strong associative value are found frequently on loaded handgun ammunition. Utilization of this new source of evidence will require adjustment of long-standing forensic examination practices and balancing the level of effort required with the utility of the resulting associations. To do this one important follow-on step is replacing the labor-intensive research laboratory methods applied in this project with more efficient technologies available in forensic laboratories.

The project produced datasets that include images of 415 non-identifiable fingermarks in .tif format, and corresponding images with annotation of fingermark minutiae in .jpg format. The accompanying spreadsheets contain summary information for each of 1263 rounds of ammunition (number of identifiable and non-identifiable fingermarks found, the number of annotated minutiae for the marks, the handgun type - semi-automatic vs. revolver - and the caliber class), as well as the results from each of the handguns sampled.

Most footwear evidence in the United States is evaluated on the basis of class characteristics, without regard for individualizing information. Unfortunately, it is very difficult to assess the strength of a class characteristic match due to lack of data about the frequency of class characteristics within a population. This project addresses the lack of data through the development of equipment and software which can automate the data collection process. The data include images taken with the prototype shoe scanner on a college campus located in Ames, Iowa.

For additional information, see the project's final report prepared for the National Institute of Justice.

This 2020 study was funded by the National Institute of Justice to advance knowledge about the microscopical methods used to examine materials commonly found in commercial and improvised low explosives. To achieve this, researchers developed reference documentation and an "Atlas of Unburned, Partially Burned, and Fully Burned Low Explosive and Related Materials" for the characterization, comparison, and identification of such materials. This data collection includes 57 files with images and descriptive captions documenting methods of microscopical analysis for a variety of chemically reacted, improvised low explosives and related residues. Details on the optical and physical properties, information regarding chemical solubility, recrystallization, microcrystal and microchemical spot tests, melting points, potential decomposition products, references, and photomicrographs of these materials are included as a PDF table. Additional information on this research can be found on the McCrone Research Institute website.

A 2016 needs assessment conducted by the National Institute of Standards and Technology's Organization of Scientific Area Committees for Forensic Science (NIST/OSAC) Crime Scene Investigation (CSI) Subcommittee identified the decontamination of crime scene equipment as a gap that must be addressed. Currently, there are no widely accepted standard operating procedures (SOP) and/or best practices for crime scene investigators to follow regarding equipment decontamination. Furthermore, to date, there has been no peer-reviewed published research to assess the effectiveness of the different decontamination methods that are currently employed by crime laboratories and law enforcement agencies involved in crime scene investigations. Ineffective decontamination of crime scene equipment has the potential to lead to cross-contamination between scenes as well as secondary transfer to evidence after contact with equipment. With increased sensitivity of current DNA analysis protocols, the ineffective decontamination of CSI equipment has implication for wrongful convictions due to potential secondary DNA transfer.

To address this gap, and in response to the NIST/OSAC needs assessment, RTI International (RTI) performed a comprehensive evaluation of several decontamination methods on commonly used CSI equipment to provide the community with evidence-based recommendations of effective decontamination protocols. RTI identified reusable CSI equipment that is most likely to be contaminated with biological material after use at a crime scene based on literature searches, crime laboratory SOP reviews, and discussions with crime scene practitioners. Seven types of crime scene-related equipment were used to determine the extent of the effectiveness of nine frequently used decontamination methods. The total amount of DNA remaining on the equipment after a controlled decontamination was quantified using Quantifiler Trio DNA Quantification Kit and processed for short tandem repeat markers (STRs) with GlobalFiler. Quantifiler Trio includes a degradation index (DI) that provides an estimation of the quality of DNA in potentially degraded samples.

The research team sought to create a methodology and software that allows for identification of deceased individuals based on iris patterns, with computer- and human-driven components. Using a dataset of post-mortem and peri-mortem iris images (acquired in near infrared and visible light) representing 259 cases, the research team engineered a software package, PMExpert, that incorporated three post-mortem specific iris matching algorithms. To understand what features humans believe to be useful in post-mortem iris matching, participants analyzed pairs of post-mortem samples, classified them as those originating from the same or different eyes, and annotated features supporting the decision.

Iris Images:

After the curation of all data collected by the Dutchess County Medical Examiner's Office, NY, iris images from 259 cases were selected for the final dataset release, and for analyses carried out in this project. This data corpus consists of 5,770 NIR and 4,643 RGB images, including images for one peri-mortem case with corresponding post-mortem samples after demise.

Human Examination Data:

The researchers conducted an experiment to collect annotation data on what humans believe to be distinctive features useful for post-mortem iris matching. Initial participants were recruited through the University of Notre Dame to complete study tasks in-person on-site. Due to the COVID-19 pandemic, the study design was later modified to be an online experiment recruiting participants through Amazon Mechanical Turk.

This data acquisition took place in two rounds:

1. The first round was the initial collection of annotation data wherein participants had no prior knowledge of the task or previous decisions.
2. The second round, called the verification step, is where the annotations collected in the first round were presented to future participants for them to either agree with or disagree with along with supporting annotations.

Software Package:

A software tool called PMExpert was created to provide a simple unified interface for all recognition methods, allowing them to be used in an operational setting.

PMExpert consists of two main components: a command line interface (CLI) and a graphical user interface (GUI). Both components are meant to allow examiners to use post-mortem iris recognition methods on images that are collected in their routine operations, offering not only similarity scores and decisions, but also additional information to equip examiners to make their final decision.

This project evaluated whether DNA contamination can mimic the characteristics of low copy number (LCN), aged, damaged, and degraded DNA samples. Massive Parallel Sequencing/Next Generation Sequencing (MPS/NGS) was used to see if specific patterns of nucleotide damage is present with surface DNA contamination that has been aged and/or exposed to varying concentrations of sodium hypochlorite (bleach) and ultraviolet (UV). The project included two phases.

• Phase 1.0: Understand the process and rate of degradation and damage of applied touch DNA contamination on human skeletal remains and evidence tape. Five time intervals (ranging from 0 days to 1 year), three bleach treatments, and three UV treatments were tested. Two additional handlers (cumulative) created a scenario of minor contributors often encountered in forensic scenarios.
• Phase 2.0: Understand the utility and degradation of the skin microbiome associated with touch DNA. This included determining if unique forensic signatures can be identified and compared, especially on bone substrates that may have their own microbiome signature.

The Ignitable Liquids Reference Collection (ILRC) and Substrate databases contain separate compilations of data from reference materials that is intended for use by forensic analysts to conduct fire debris analysis. The ILRC, Substrate, and Fire Debris databases were redesigned and made available on a single website to enhance usability in casework and research. This project also investigated the construction of digital fire debris data by mixing ignitable liquid and substrate(s) digital data. Total ion chromatograms and total ion spectra of in silico fire debris were created from data in the Ignitable Liquids Reference Collection and Substrate databases. In silico mixing provides the ability to develop large data sets for machine learning.

The overall goal of this project was to understand the degradation characteristics of mRNA molecules in dried body fluid stains such that the relationship between degradation and the passage of time could be explored and used to develop a forensic tool to estimate the age of the stain (i.e., determine the time since deposition, TsD). Research has demonstrated that RNA degradation correlates with the passage of time in dried stains and have defined degradation kinetics for multiple mRNA transcripts present in dried blood, semen, and saliva stains. The current study collected detailed degradation kinetics for multiple transcripts in stains stored in real world environments with varying conditions of temperature, relative humidity, and sunlight exposure. Results suggest it may be possible to model degradation kinetics mathematically and develop an algorithm useful for estimating TsD in biological evidence recovered from crime scenes.

Fingermark identification remains one of the most important and unambiguous approaches to place perpetrators at crime scenes. While a great number of forensic techniques for the visualization of latent marks already exist, they all suffer from one or more shortcomings such as: limited applicability with regard to the age of a mark or the nature of the surface it was deposited on ("substrate"); the requirement of expensive laboratory equipment and special training; and the potential to alter or even destroy evidence, or at least leave a visible record of their application.

The goal of this project was to develop and validate novel fingermark lifters, which allow instantaneous, on-the-spot visualization of marks. The underlying detection principle used with these lifters is based on the reaction of either pH-sensitive or amine-reactive substances - immobilized on suitable solid supports such as membranes - with chemicals contained in fingermark residues (e.g., lactic acid, amino acids, proteins, and amino sugars). The exposure of appropriate reagents to such an environment causes a change in their spectroscopic properties, which can be seen, depending on the type of reagent, either under ambient or luminescent light conditions.

This study examines the radicalization of Western women to extremist violence, both through the creation of a moral-situational-action risk model and the examination of their responses to various types of online propaganda. The Moral-Situational-Action Risk Model for Extremist Violence (MSA-RMEV) was developed using situational action theory from criminology and violence risk practice literature. The MSA-RMEV revolves around three domains reflective of propensity, mobilization, and capacity building, geared towards providing a violence risk assessment that can assist the intelligence community in preventing future acts of violence.

A sample of women who self-identified as conservative, liberal, and Muslim were exposed to jihadist, alt-right, and alt-left online propaganda. Physiological responses and self-report assessments were recorded. Eye-gaze, pupil dilation, galvanic skin response, heart rate, and facial emotions were documented, along with women's judgment of their emotional, cognitive, and arousal states, while viewing propaganda.

Based on their results, women were categorized as high-risk, medium-risk, or low-risk for violence. Additionally, numerous variables were created to identify participant's beliefs and behavior related to radicalization. Beliefs included religiosity, political affiliation, the presence of moral emotions, sacred values, developmental maturity, and militant thinking. Behaviors included group affiliations, extent of involvement in extremist activities, and presence on social media platforms such as Facebook, Reddit, and Twitter. Demographic variables such as age, marital status, number of children, race, ethnicity, country of origin, and educational status were included.