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Few studies have explored aggregated DNA analysis findings from sexual assault kits (SAKs) and predictive features of developing useful DNA information related to the foreign contributor(s). Information gleaned from evaluating DNA analysis findings have significant practice and policy implications for both forensic medical examiners/sexual assault nurse examiners and forensic scientists. Results from this innovative study were obtained by tracking SAKs from evidence collection, data from sexual assault medical forensic examinations, through DNA analysis results, and data from publicly funded laboratories.

This study does not include data files. It includes 13 Python files used for statistical analysis.

This data collection contains data from the 2020 Census of Publicly Funded Forensic Crime Laboratories (CPFFCL). The CPFFCL collected data on organizational characteristics, functions, budget, staffing, workload, resources, and quality assurance practices of publicly funded forensic crime laboratories operating in the U.S. and serving federal, state, and local jurisdictions. The CPFFCL includes crime labs that employed one or more full-time scientists who possess a minimum of a bachelor's degree in chemistry, physics, biology, criminalistics, forensic science or a closely related field and whose principal functions are examining physical evidence in criminal matters and providing reports and testimony to courts of law with respect to such evidence. Private laboratories were excluded from the CPFFCL. Laboratories may operate independently or as part of a larger system. Respondents to the CPFFCL could choose to respond as individual labs or as one system. A total of 423 individual labs, constituting 326 standalone labs and multilab systems, received the questionnaire. A total of 382 (90%) individual labs responded to the 2020 CPFFCL and 293 (90%) standalone labs and multilab systems responded. For the 2020 study, data were collected from July 2021 to February 2022.

The Bureau of Justice Statistics (BJS) first surveyed forensic crime laboratories in 1998, focusing solely on agencies that performed DNA analysis. The National Institute of Justice (NIJ) funded the 1998 study as part of its DNA Laboratory Improvement Program. The BJS' National Study of DNA Laboratories was repeated in 2001. An expanded version of the data collection, called the Census of Publicly Funded Forensic Crime Laboratories, was first conducted among all forensic crime laboratories in 2002.

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.

This study examined arrestee DNA laws (laws that allowed testing of arrestees DNA pre-adjudication), their implementation in the field and their subsequent effects on agency operations as well as their success in aiding investigations in the 28 states that have these laws. The study investigated five specific questions:

1. What states have passed legislation authorizing the collection of DNA from arrestees?
2. How do the laws and policies regarding collecting DNA from arrestees differ by state?
3. How have the courts ruled on these new laws?
4. How have arrestee DNA laws been implemented in each state?
5. What has been the impact of requiring DNA collection from arrestees on state crime laboratories and other involved agencies?
6. What evidence is available to determine the effects of collecting DNA from arrestees on public safety or other criminal justice outcomes?

To answer these questions, researchers used a mixed methods data collection plan, including reviewing relevant statutes and case law, interviewing state and federal Combined DNA Index System (CODIS) laboratory staff and other forensic experts, and collecting descriptive data from state laboratories.

This study examined the laws, policies, and practices related to juvenile DNA collection, as well as their implications for the juvenile and criminal justice systems. DNA evidence proved valuable in solving crimes, which motivated a concerted effort to expand the categories of offenders who provided DNA samples for analysis and inclusion in the Combined DNA Index System (CODIS), the Federal Bureau of Investigation (FBI)-operated national database.

State requirements for DNA collection, which initially focused on adult offenders convicted of sexual or violent offenses, expanded to include other categories of convicted felons, convicted misdemeanants, arrestees, and juveniles. In 30 states, certain categories of juveniles handled in the juvenile justice system must now provide DNA samples. The study was designed to explore the practice and implications of collecting DNA from juveniles and addressed the following questions:

1. How have state agencies, juvenile justice agencies and state laboratories implemented juvenile DNA collection laws?
2. What were the number and characteristics of juveniles with profiles included in CODIS?
3. How have juvenile profiles in CODIS contributed to public safety or other justice outcomes?
4. What improvements to policies and practices needed to be made?

To examine these questions, researchers at the Urban Institute: (1) systematically reviewed all state DNA statutes; (2) conducted semi-structured interviews with CODIS lab representatives in states that collect DNA from juveniles to understand how the laws were implemented; (3) collected and analyzed descriptive data provided by these labs on the volume and characteristics of juvenile profiles in CODIS; (4) conducted semi-structured interviews with juvenile and criminal justice stakeholders in five case study states; and (5) convened a meeting of federal officials and experts from the forensic and juvenile justice committees to explore the broader impacts of juvenile DNA collection.

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.

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 investigated the use and value of digital evidence (DE) to create an evidence base for more efficient and effective DE management and processing. Researchers aimed to assess existing laboratory protocols and better understand the scientific rationale underpinning existing laboratory processes with the ultimate goal of assisting law enforcement agencies and crime laboratories in eliminating backlogs, optimizing available resources, and decreasing justice delays. The data deposited with ICPSR include the Crime Laboratories Survey Data, which describe the processes used by crime laboratories to manage and analyze DE, and the Law Enforcement Agencies Survey Data, which includes information on methods and processes for DE seizure, management, and analysis, and data about coordination between law enforcement agencies and associated crime laboratories.

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.

The Pilot Study of State and Federal Digital Evidence Laboratories data collection contains data collected in 2015 as part of the Census of Publicly Funded Forensic Crime Laboratories (CPFFCL). The CPFFCL examined the forensic services provided by publicly funded crime labs across the nation and the resources devoted to completing the work.

To capture more information about an emerging forensic science discipline known as digital evidence, the Bureau of Justice Statistics (BJS) expanded the scope of the 2014 CPFFCL from previous data collections to include a separate pilot study of state and federal agencies that solely analyzed digital evidence in support of criminal investigations and prosecutions. These agencies obtained digital and multimedia evidence in various formats, including audio, video, and graphical images from computers, cell phones, cameras, and other electronic devices. The traditional CPFFCL definition of a crime lab limited the information collected about digital evidence since some agencies only handle this type of evidence and employ forensic experts with training in computer science or information technology as opposed to natural sciences such as chemistry and biology.

The census collected detailed information on laboratory staff, budgets, workloads, and backlogs in requests for forensic services. The census also provides data on lab accreditations, proficiency tests, and other quality assurances.

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.

This project had four goals/areas of examination.

1. Examine the current state of the National Integrated Ballistic Information Network (NIBIN) implementation nationally and at partner sites.
2. Examine the impediments and facilitators of successful implementation of NIBIN.
3. Understand the extent to which NIBIN helps identify suspects and increase arrests for firearms crimes.
4. Understand best practices for the implementation of NIBIN at agencies and for criminal investigations.

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

This collection includes data gathered through three separate study designs. The first study called for tracking cases and forensic evidence through local criminal justice processes for five offenses: homicide, sexual assault, aggravated assault, robbery and burglary. Two sites, Denver, Colorado, and San Diego, California, participated in the study. Demographic data were collected on victims (Victim Data n = 7,583) and defendants (Defendant Data n = 2,318). Data on forensic evidence collected at crime scenes included DNA material (DNA Evidence Data n = 1,894), firearms evidence (Ballistics Evidence Data n = 488), latent prints (Latent Print Evidence Data n = 766), trace evidence (Other Impressions Evidence Data n = 49), and drug evidence (Drug Evidence Data n = 43). Comparisons were then made between open and closed cases from the participating sites. Two smaller studies were conducted as part of this grant. The second study was an analysis of an experiment in the Miami-Date, Florida Police Department (Miami-Data County Data n = 1,421) to determine whether clearance rates for no-suspect property crimes could be improved through faster processing of DNA evidence. The third study was a survey of 75 police departments across the nation (Crime Labs Survey Data) to obtain information on the organizational placement, staffing and responsibilities of crime lab units.

In the current study, roughly 170 single source samples and 32 two-person mixture samples were tested using both the integrated Quantiplex®-high resolution melt (HRM) assay and Quantifiler™ Trio-HRM assay, then the entire HRM datasets were exported for prediction modeling using both linear discriminate analysis (LDA) and support vector machine (SVM) algorithms in R Studio software. For proof-of-concept, only 8 different genotypes, including a genotype of "mixture", were represented (for each locus) in testing. A portion of the samples tested were used to "train" the software and the remaining sample data was used as unknowns (or "validation") samples for prediction. When samples were tested in the Quantiplex®-HRM assay, an overall accuracy of 87.88 percent was exhibited, correctly classifying 87.5 percent of single source samples as such and 90 percent of mixture samples. Similarly, when samples were tested in the Quantifiler™ Trio-HRM assay an overall accuracy of 79.2 percent was exhibited, with 89.2 percent of single source samples accurately classifying and 43.8 percent of mixtures accurately classifying. Additionally, quantification values obtained from the integrated assays as well as the quality metrics such as the slope, R2, and y-intercept, were not significantly different than those obtained in the standard assays.

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.

Seeking to measure the usage of Familial DNA Searching (FDS) to aid in criminal investigations, this study utilized a multi-phase, mixed methods approach to obtain data on FDS policies and practices in the United States. This study includes data from the National Survey of CODIS Laboratories, which was compiled after two expert roundtables, a literature and policy scan of practice, cost modeling, and state case studies.

The study includes one SPSS data file: FDS_National_Survey_of_CODIS_Labs_Data.sav