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Showing 1 – 41 of 41 results.

Curated

Assessment of Sexual Assault Kit (SAK) Evidence Selection Leading to Development of SAK Evidence Machine-Learning Model (SAK-ML Model), California, Idaho, Utah, 2010-2022 (ICPSR 39161)

Released/updated on: 2025-06-26

Geographic coverage: United States, California, Utah, Idaho

Time period: 2010-01-01--2022-01-01, 2015-01-01--2020-01-01, 2013-01-01--2020-01-01

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.

Curated

Children's Out-of-Court Statements: Effects of Hearsay on Jurors' Decisions in Sacramento County, California, and Maricopa County, Arizona, 1994-1997 (ICPSR 2791)

Released/updated on: 2006-03-30

Geographic coverage: United States, California, Arizona

Time period: 1994-01-01--1997-01-01

The goal of this project was to investigate the effects of children's out-of-court hearsay statements on jurors' perceptions of witness credibility and defendant guilt. To accomplish this goal, three studies were conducted. The studies represented a series of increasingly ecologically valid investigations: mock jurors' perceptions of children's live and hearsay statements about a mock crime (Study 1), mock jurors' perceptions of real child sexual abuse victims' hearsay statements (Study 2), and actual jurors' perceptions of real child sexual abuse victims' hearsay statements (Study 3). In these contexts, "hearsay statements" are the repetition of a child's out-of-court statements in a court trial, either via a videotaped recording of the child's testimony in a forensic interview with a social worker or as described by an adult (the social worker or a police officer) who interviewed the child. The three studies permitted researchers to examine factors that jurors use to evaluate the reliability of children's hearsay evidence. The mock crime in Study 1 was touching the child on the stomach, nose, or neck. Jurors were instructed to consider those acts as if they were battery against a child. In Study 1, elaborate mock trials concerning the above mock crime were conducted under three trial conditions: (1) the child testified live in court, (2) a videotape of a simulated forensic interview with the child was presented, or (3) adult hearsay was presented (i.e., a social worker testified about what the child had said in the simulated forensic interview). A total of 370 mock jurors participated in Study 1, which was conducted in Sacramento County, California. In Study 2, videotapes of actual forensic interviews from real child sexual abuse cases were incorporated into mock trials instead of having live child testimony. The last two trial conditions in Study 2 were the same as those for Study 1, except that a police officer provided the adult hearsay testimony instead of a social worker. For Study 2, 170 mock jurors served on 15 main juries, which were held in Sacramento County, California. For both Studies 1 and 2, pre- and post-deliberation questionnaires were completed by mock jurors to ascertain their views on the credibility of the child and adult testimonies, the importance of various pieces of evidence, and the guilt of the defendant. Demographic questionnaires were also filled out before the mock trials. In Study 3, real jurors from actual child sexual abuse trials were surveyed regarding their judgments of child and adult testimonies. The three trial conditions that were present in Studies 1 and 2 (live child testimony, videotaped testimony, and adult hearsay testimony) were also experienced by the Study 3 participants. These jurors also indicated the importance of various types of evidence and provided demographic data. A total of 248 jurors representing 43 juries from Sacramento County, California, and Maricopa County, Arizona, participated in Study 3. This collection includes aggregated data prepared from the Study 3 data to provide mean values for each of the 42 juries, as calculated from the individual juror responses. Data for one jury were eliminated from the aggregated data by the principal investigators. Variables from the demographic questionnaire for Studies 1 and 2 include trial condition, respondent's age, gender, marital status, occupation, ethnic background, religious orientation, and highest grade attained in school, if the respondent supported the death penalty, if the respondent was ever a victim of crime, number of children the respondent had, if the respondent was a United States citizen, if the respondent's native language was English, and if he or she had ever been a police officer, a convicted felon, a lawyer, or a judge. The pre-deliberation questionnaire for Study 1 asked jurors if they felt that the defendant was guilty, and how confident they were of the defendant's guilt or innocence. Jurors were also asked to assess the accuracy of various facts as given in the social worker's interview of the child and the child's statements in the taped interview, and what the likelihood was of the child's being influenced by the social worker, prosecutor, and/or defense attorney. Questions about the trial included the juror's assessment of the defendant, the social worker, and the research assistant. Jurors were also asked about the influence of various factors on their decisions regarding whether to believe the individuals in the case. Jurors' open-ended comments were coded on the most important factors in believing or doubting the child or the social worker, the most important evidence in the case, and whether anything could have been done to make the trial more fair. Post-deliberation questions in Study 1 included whether the defendant was guilty, how confident the juror was of the defendant's guilt or innocence regarding various charges in the case, and the final verdict of the jury. Questions similar to those in Study 1 were asked in the pre-deliberation questionnaire for Study 2, which also included respondents' opinions of the police officer, the mother, the doctor, and the use of anatomical dolls. The Study 2 post-deliberation questionnaire included questions on whether the defendant was guilty, how confident the juror was of the defendant's guilt or innocence, and the juror's assessment of the social worker's videotaped interview and the police officer's testimony. Variables from the Study 3 juror survey include the county/state where the trial was held, the juror's age, gender, ethnic background, and highest grade attained in school, if the juror supported the death penalty, if he or she was ever a victim of crime, and the amount of contact he or she had with children. Questions about the trial include the number of children the defendant was charged with abusing, the main child's age and gender, if a videotape was shown at trial, who interviewed the child on the videotape, the impact of seeing the videotape on the juror's decision to believe the child, the number of children who testified at the trial, and if the child was involved in a custody dispute. Additional questions focused on the defendant's relationship to the main child, who the first person was that the child told about the abuse, if the main child testified in court, the most important evidence in the case in the opinion of the juror, the jury's verdict, and how fair the juror considered the trial. Finally, jurors were asked about the influence of various factors on their decision to believe or doubt the individuals in the case. Data in Study 3 also include coded open-ended responses to several questions. Variables provided for the Study 3 aggregated data consist of the calculated mean values for each of the 42 juries for most of the variables in the Study 3 juror survey data.

Curated

Collecting DNA at Arrest: Policies, Practices, and Implications, in 28 States, 2005-2012 (ICPSR 34682)

Released/updated on: 2016-09-28

Geographic coverage: North Carolina, Vermont, Oklahoma, Tennessee, Alabama, Arkansas, Utah, South Carolina, Colorado, Missouri, Alaska, North Dakota, Arizona, South Dakota, Minnesota, California, Kansas, Florida, New Jersey, Michigan, New Mexico, Illinois, Texas, Connecticut, Louisiana, Ohio, Virginia, Maryland

Time period: 1997-01-01--2011-01-01

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:

What states have passed legislation authorizing the collection of DNA from arrestees?
How do the laws and policies regarding collecting DNA from arrestees differ by state?
How have the courts ruled on these new laws?
How have arrestee DNA laws been implemented in each state?
What has been the impact of requiring DNA collection from arrestees on state crime laboratories and other involved agencies?
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.

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Detection and Identification of Hair Dyes by Surface-Enhanced Raman Spectroscopy (SERS), 2021-2026 (ICPSR 39772)

Released/updated on: 2026-03-25

Time period: 2021-01-01--2026-01-01

The primary goal of this project is to develop and deploy Surface-Enhanced Raman Spectroscopy (SERS) as a confirmatory, rapid, and minimally destructive tool for the forensic analysis of colorants directly on human hair at a crime scene.

There are several datasets associated with this study that are available for download.

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Development of Microscopical Methods for the Systematic Analysis of Chemically Reacted, Improvised Low Explosives and Related Residues, Chicago, Illinois, 2020-2023 (ICPSR 39116)

Released/updated on: 2025-05-29

Geographic coverage: United States, Chicago, Illinois

Time period: 2020-01-01--2023-01-01

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.

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Efficiency in Processing Sexual Assault Kits in Crime Laboratories and Law Enforcement Agencies, United States, 2013-2014 (ICPSR 36747)

Released/updated on: 2018-11-29

Geographic coverage: United States

Time period: 2013-01-01--2014-01-01

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 study presents a research-informed approach to identify the most efficient practices for addressing un-submitted sexual assault kits (SAKs) that accrue in U.S. law enforcement agencies (LEAs) as well as untested SAKs pending analysis in crime laboratories. The study examined intra- and interagency dynamics associated with SAK processing efficiency in a linked sample of crime laboratories. SAK outputs and inputs were assessed for laboratories that conduct biological forensic analysis and LEAs that submit SAK evidence to these laboratories. Production functions were estimated to examine effects of labor and capital inputs, in addition to policies, management systems, and cross-agency coordination on efficiency. Six jurisdictions were recruited for site visits, and qualitative methods were used to understand how LEAs, laboratories, and prosecutors implement practices that affect efficiency.

This study contains 7 data files including:

Crime Lab_Raw.dta (n=147; variables =242)
Crosswalk File.dta (n=2337; variables=2)
lab_analysis_sample_2017-04-06.dta (n=132; variables=92)
LEA Communication LCAs.dta (n=321; variables=15
merged_analysis_file_JH2017-04-30.dta (n=273; variables=117)
policy Class probabilities_LABS.dta (n=139; variables=19)
SAK LAB COMMUNICATION LCA.dta (n=134; variables=15)

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Estimating the Prevalence of Wrongful Convictions, Virginia, 1973-1987 (ICPSR 36836)

Released/updated on: 2021-09-15

Geographic coverage: United States, Virginia

Time period: 1973-01-01--1987-01-01

This study extends research on wrongful convictions in the United States and the factors associated with justice system errors that lead to the incarceration of innocent people. Among cases where physical evidence produced a DNA profile of known origin, 12.6 percent of the cases had DNA evidence that would support a claim of wrongful conviction. Extrapolating to all cases in our dataset, the investigators estimate a slightly smaller rate of 11.6 percent. This result was based on forensics, case processing, and disposition data collected on murder and sexual assault convictions in the 1970s and 1980s across 56 circuit courts in the state of Virginia. To address limitations in the amount and type of information provided in forensic files that were reviewed in the Urban Institute's prior examination of these data, the current research includes data collected through a review of all publicly available documents on court processes and dispositions across the 714 convictions, which the investigators use to reassess prior estimates of wrongful conviction.

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Evaluating the Impact of a Specialized Domestic Violence Police Unit in Charlotte, North Carolina, 2003-2005 (ICPSR 20461)

Released/updated on: 2008-07-01

Geographic coverage: North Carolina, Charlotte, United States

Time period: 2003-01-01--2005-01-01

The specific goals of this project were (1) to assess the selection criteria used to determine the domestic violence cases for intensive intervention: what criteria are used, and what differentiates how cases are handled, (2) to track the outcomes through Charlotte-Mecklenburg Police Department (CMPD), Mecklenburg domestic violence court, and the Mecklenburg jail for the different methods of dealing with the cases, and (3) to provide an assessment of the relative effectiveness of a specialized domestic violence unit vis-a-vis normal patrol unit responses in terms of repeat calls, court processing, victim harm, and repeat arrests. The population from which the sample was selected consisted of all police complaint numbers for cases involving domestic violence (DV) in 2003. The unit of analysis was therefore the domestic violence incident. Cases were selected using a randomized stratified sample (stratifying by month) that also triple-sampled DV Unit cases, which generated 255 DV Unit cases for inclusion. The final sample therefore consists of 891 domestic violence cases, each involving one victim and one suspect. Within this final sample of cases, 25 percent were processed by the DV Unit. The data file contains data from multiple sources. Included from the police department's computerized database (KBCOPS) are variables pertaining to the nature of the crime, victim information and suspect information such as suspect and victim demographic data, victim/offender relationship, highest offense category, weapon usage, victim injury, and case disposition status. From police narratives come such variables as victim/offender relationship, weapon use (more refined than what is included in KBCOPS data), victim injury (also a more refined measure), and evidence collected. Variables from tracking data include information regarding the nature of the offense, the level/type of harm inflicted, and if the assault involved the same victim in the sample. Variables such as amount of jail time a suspect may have had, information pertaining to the court charges (as opposed to the charges at arrest) and case disposition status are included from court and jail data.

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Evaluation of Digital Evidence Processing Efficiencies in Publicly Funded Crime Laboratories, United States, 2020-2023 (ICPSR 38998)

Released/updated on: 2025-12-16

Geographic coverage: United States

Time period: 2020-01-01--2023-01-01

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.

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Evaluation of the Bureau of Justice Assistance Sexual Assault Kit Initiative, United States, 2018 (ICPSR 37897)

Released/updated on: 2022-03-30

Geographic coverage: United States

Since 2015, the Bureau of Justice Assistance (BJA) has funded sites to engage in reforms intended to improve the national response to sexual assault cases. The goals of this initiative are to (1) create a coordinated community response that ensures just resolution to unsubmitted sexual assault kit (SAK) cases through a victim-centered approach and (2) build jurisdictions' capacity to prevent the development of conditions that lead to high numbers of unsubmitted sexual assault kits. Site efforts to address these issues include agencies such as law enforcement, prosecution, forensic laboratories, and victim advocacy service organizations. Westat was awarded a contract by the National Institute of Justice (NIJ) to assess components of BJA's Sexual Assault Kit Initiative (SAKI). The study includes (1) an evaluability assessment of 17 sites to determine their readiness for an evaluation, (2) a process evaluation and system reform assessment of the 17 sites, (3) a feasibility assessment of using case level data for an outcome evaluation, and analysis of a subset of unsubmitted SAK cases to identify how characteristics of incidents, offenders, and victims are associated with case processing decisions and outcomes, and (4) development of a long-term outcome evaluation plan.

Two sources of data are archived with NAJCD: (1) coded qualitative data from primarily on-site interviews the Westat Team conducted in 2018 with stakeholders from 17 of the fiscal year (FY) 2015 SAKI grantees and 2 private lab facilities and 2) quantitative case-level data from the 2 FY 2015 SAKI grantees on SAKI cases associated with previously unsubmitted sexual assault kits that were determined to contain foreign DNA or biological evidence through laboratory testing. The interview data file contains coded data from 172 interviews the research team conducted with one or more agency representatives regarding their organization's goals, strategies, and activities for processing sexual assault kits, and associated lessons learned, challenges, and expected outcomes. The quantitative case-level data file includes case-level information on 576 sexual assault kits determined to have DNA and associated cases included in the 2 sites' SAKI inventories. The case-level data captures information on case or offense-level information (e.g., date of offense, date offense reported to police, number of victims and suspects involved, investigation and prosecution activities), victim-level information (e.g., victim age, sex, race, participation in investigation), and suspect-level information (e.g., suspect's age, race, sex, criminal history).

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Evaluation of the Phoenix, Arizona, Homicide Clearance Initiative, 2003-2005 (ICPSR 26081)

Released/updated on: 2011-07-05

Geographic coverage: United States, Phoenix, Arizona

Time period: 2003-07-01--2005-06-30

The purpose of the study was to conduct a process and outcome evaluation of the Homicide Clearance Project in the Phoenix, Arizona Police Department. The primary objective of the Homicide Clearance Project was to improve homicide clearance rates by increasing investigative time through the transfer of four crime scene specialists to the homicide unit. In 2004, the Phoenix Police Department received a grant from the Bureau of Justice Assistance providing support for the assignment of four crime scene specialists directly to the department's Homicide Unit. Responsibilities of the crime scene specialists were to collect evidence at homicide scenes, prepare scene reports, develop scene diagrams, and other supportive activities. Prior to the project, homicide investigators were responsible for evidence collection, which reduced the time they could devote to investigations. The crime scene specialists were assigned to two of the four investigative squads within the homicide unit. This organizational arrangement provided for a performance evaluation of the squads with crime scene specialists (experimental squads) against the performance of the other squads (comparison squads). During the course of the evaluation, research staff coded information from all homicides that occurred during the 12-month period prior to the transfers (July 1, 2003 - June 30, 2004), referred to as the baseline period, the 2-month training period (July 1, 2004 - August 31, 2004), and a 10-month test period (September 1, 2004 - June 30, 2005). Data were collected on 404 homicide cases (Part 1), 532 homicide victims and survivors (Part 2), and 3,338 records of evidence collected at homicide scenes (Part 3). The two primary sources of information for the evaluation were investigative reports from the department's records management system, called the Police Automated Computer Entry (PACE) system, and crime laboratory reports from the crime laboratory's Laboratory Information Management System (LIMS). Part 1, Part 2, and Part 3 each contain variables that measure squad type, time period, and whether six general categories of evidence were collected. Part 1 contains a total of 18 variables including number of investigators, number of patrol officers at the scene, number of witnesses, number of crime scene specialists at the scene, number of investigators collecting evidence at the scene, total number of evidence collectors, whether the case was open or closed, type of arrest, and whether the case was open or closed by arrest. Part 2 contains a total of 37 variables including victim characteristics and motives. Other variables in Part 2 include an instrumental/expressive homicide indicator, whether the case was open or closed, type of arrest, whether the case was open or closed by arrest, number of investigators, number of patrol officers at the scene, number of witnesses, and investigative time to closure. Part 3 contains a total of 46 variables including primary/secondary scene indicator, scene type, number of pieces of evidence, total time at the scene, and number of photos taken. Part 3 also includes variables that measure whether 16 specific types of evidence were found and the number of items of evidence that were collected for 13 specific evidence types.

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Eyewitness Identification: A Systematic Investigation of Lineup Composition and Fairness, United States, 2019-2022 (ICPSR 38761)

Released/updated on: 2025-06-26

Geographic coverage: United States

Time period: 2019-01-01--2022-01-01

The major objective of this project was to investigate photo array composition in order to improve eyewitness identification procedures. Photo array composition involves the fillers, or known-innocent individuals that police add to a photo array so that the perpetrator/suspect (referred to as the "target" in experimental design) does not stand out. An unbiased (fair) photo array contains fillers that match the description of the suspect provided by one or more eyewitnesses. In contrast, in a biased photo array, the suspect stands out from the fillers. Another popular procedure used by police is the showup, when the suspect is presented without any fillers. This project involved all three of these procedures.

This collection contains raw and aggregated data from 12 sets of experiments that investigated different aspects of eyewitness identification, including fair vs. biased lineups, lineup size, distinctive facial features, target-filler similarity, impact of sleep on eyewitness accuracy, memory strength, number of suspects presented, impact of courtroom instructions and expert expertise, and speed and confidence of eyewitness identification. Each experiment set followed a similar general design, with variations based on the purpose and hypotheses of the specific study. United States-based adult participants recruited via SurveyMonkey were asked to complete an online experiment in which they would be presented with a crime vignette and a suspect facial image (created from a faces database), given a distractor task, and then asked to select the suspect from a lineup and rate the confidence level of their decision.

The data were provided to ICPSR in Excel workbook format (41 data files, 3 codebooks) and are available for download as a zipped package. ICPSR has not modified the files from the format in which they were supplied. Data files are organized into subfolders that are named with a short content descriptor and citation of the relevant publication. Unless noted, data files contain a "codes" sheet that explains the variables and experimental condition groups. Articles and theses/dissertations that used each dataset are available under Data-related Publications. Please refer to the ICPSR README for more information.

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Forensic Evidence and Criminal Justice Outcomes in Sexual Assault Cases in Massachusetts, 2008-2012 (ICPSR 35205)

Released/updated on: 2017-03-30

Geographic coverage: Massachusetts

Time period: 2008-01-01--2012-01-01

This project had three goals. One, to provide a more detailed description of injury evidence and biological evidence in sexual assault cases, including their timing relative to arrests. A second goal was to examine the relationship of forensic evidence to arrests. A third goal was to examine injury evidence and biological evidence in certain types of cases in which it may have had greater impact. To achieve these goals, the researchers created analysis data files that merged data from the Massachusetts Provided Sexual Crime Report, forensic evidence data from the two crime laboratories serving the state and data on arrests and criminal charges from 140 different police agencies.

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Forensic Evidence and the Police, 1976-1980 (ICPSR 8186)

Released/updated on: 2006-01-18

Geographic coverage: United States, Chicago, Illinois, Missouri, Peoria, Kansas City (Missouri), California, Oakland

Time period: 1976-01-01--1980-01-01

This data collection focuses on adult cases of serious crime such as homicide (and related death investigations), rape, robbery, aggravated assault/battery, burglary, and arson. Data are included for Peoria, Illinois, Chicago, Illinois, Kansas City, Missouri, and Oakland, California. The data consist of police, court, and laboratory records from reports submitted by police personnel during investigations of suspected criminal offenses. The primary source of information was police case files. Prosecutor and court files were reviewed for information regarding the disposition of suspects who were arrested and formally charged. Crime laboratory reports include information concerning the evidence submitted and the examiner's worksheets, notes, and final results. There are eight files in this dataset. Each of the four cities has one file for cases with physical evidence and one file for cases in which physical evidence was not collected or examined.

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Forensic Evidence in Homicide Investigations, Cleveland, Ohio, 2008-2011 (ICPSR 36202)

Released/updated on: 2018-02-13

Geographic coverage: United States, Ohio, Cleveland

Time period: 2008-01-01--2011-01-01

The objective of this study was to determine how homicide investigators use evidence during the course of their investigations. Data on 294 homicide cases (315 victims) that occurred in Cleveland between 2008 and 2011 was collected from investigative reports, forensic analysis reports, prosecutors and homicide investigators, provided by the Cleveland Ohio Police Department, Cuyahoga County Medical Examiner's Office, and Cuyahoga County Clerk of Courts.

The study collection includes 1 Stata data file (NIJ_Cleveland_Homicides.dta, n=294, 109 variables).

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Impact of Forensic Evidence on Arrest and Prosecution (IFEAP) in Connecticut, United States, 2006-2009 (ICPSR 36695)

Released/updated on: 2018-04-09

Geographic coverage: Connecticut

Time period: 2006-01-01--2009-01-01

This research was conducted in two phases. Phase one analyzed a random sample of approximately 2,000 case files from 2006 through 2009 that contain forensic analyses from the Connecticut State Forensic Science Laboratory, along with corresponding police and court case file data. As with Peterson, et al. (2010), this research had four objectives: 1) estimate the percentage of cases in which crime scene evidence is collected; 2) discover what kinds of forensic are being collected; 3)track such evidence through the criminal justice system; and 4)identify which forms of forensic evidence are most efficacious given the crime investigated.

Phase two consisted of a survey administered to detectives within the State of Connecticut regarding their comparative assessments of the utility of forensic evidence. These surveys further advance our understanding of how the success of forensic evidence in achieving arrests and convictions matches with detective opinion.

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Impact of Forensic Evidence on the Criminal Justice Process in Five Sites in the United States, 2003-2006 (ICPSR 29203)

Released/updated on: 2010-10-27

Geographic coverage: Indiana, United States, Los Angeles, California, Fort Wayne, South Bend, Evansville, Indianapolis

Time period: 2003-01-01--2006-01-01

The purpose of the study was to investigate the role and impact of forensic science evidence on the criminal justice process. The study utilized a prospective analysis of official record data that followed criminal cases in five jurisdictions (Los Angeles County, California; Indianapolis, Indiana; Evansville, Indiana; Fort Wayne, Indiana; and South Bend, Indiana) from the time of police incident report to final criminal disposition. The data were based on a random sample of the population of reported crime incidents between 2003 and 2006, stratified by crime type and jurisdiction. A total of 4,205 cases were sampled including 859 aggravated assaults, 1,263 burglaries, 400 homicides, 602 rapes, and 1,081 robberies. Descriptive and impact data were collected from three sources: police incident and investigation reports, crime lab reports, and prosecutor case files. The data contain a total of 175 variables including site, crime type, forensic variables, criminal offense variables, and crime dispositions variables.

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Improving Evidence Collection Through Police-Prosecutor Coordination in Baltimore, 1984-1985 (ICPSR 9290)

Released/updated on: 2006-01-18

Geographic coverage: Baltimore, United States, Maryland

Time period: 1984-01-01--1985-01-01

The purpose of this data collection was to investigate the effects of changes in police evidence procedures and the effects of providing feedback to officers on felony case charge reductions or dismissals due to evidentiary problems. The data were designed to permit an experimental assessment of the effectiveness of two police evidence collection programs implemented on April 1, 1985. One of these was an investigative and post-arrest procedural guide. The other was an individualized feedback report prepared by prosecutors for police officers. The officer file includes information on each officer's sex and race, length of police service, and assignment changes during the study period. Data on the offender and the case files include time of arrest, information on arresting officer, original investigating officer and principal investigating officer, offense and victim characteristics, arrestee characteristics, available evidence, case processing information, and arrestee's criminal history.

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Improving the Investigation of Homicide and the Apprehension Rate of Murderers in Washington State, 1981-1986 (ICPSR 6134)

Released/updated on: 2006-01-12

Geographic coverage: United States, Washington

Time period: 1981-01-01--1986-01-01

This data collection contains information on solved murders occurring in Washington State between 1981 and 1986. The collection is a subset of data from the Homicide Investigation Tracking System (HITS), a computerized database maintained by the state of Washington that contains information on murders and sexual assault cases in that state. The data for HITS are provided voluntarily by police and sheriffs' departments covering 273 jurisdictions, medical examiners' and coroners' offices in 39 counties, prosecuting attorneys' offices in 39 counties, the Washington State Department of Vital Statistics, and the Uniform Crime Report Unit of the Washington State Association of Sheriffs and Police Chiefs. Collected data include crime evidence, victimology, offender characteristics, geographic locations, weapons, and vehicles.

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Improving the Production and Use of Forensic Science, 5 U.S. counties, 2006-2009 (ICPSR 36727)

Released/updated on: 2022-03-16

Geographic coverage: Allegheny County, Bexar County, United States, Sedgwick County, Texas, Sacramento County, California, Kansas, King County, Washington, Pennsylvania

Time period: 2006-01-01--2009-01-01

This study collection sought to thoroughly understand the creation, testing, and use of forensic science in five jurisdictions across the country. A random sample was selected of recent criminal cases in the following jurisdictions and tracked from investigation to adjudication to understand how forensic evidence functions:

Sacramento County, CA: 990 cases
Segwick County, KS: 936 cases
Allegheny County, PA: 978 cases
Bexar County (San Antonio), TX: 936 cases
King County, WA: 892 cases

The Principal Investigator sought answers to the following seven primary research questions:

How often is forensic evidence collected and analyzed and how is it used pre-arrest?
What are the outcomes of forensic evidence testing?
What is the effect of forensic evidence on arrest and charging?
How does forensic evidence affect the plea-bargaining process?
What effect does forensic evidence have on conviction and sentencing outcomes?
Does the turnaround time for analysis of forensic evidence have any impact on case disposition?
Does the institutional configuration of the crime laboratory have any effect on its productivity?

Data for the following types of forensic testing are included in this data collection: hair, fibers, glass, paint, gas chromatography / mass spectrometry (GC/MS), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy / energy dispersive x-ray spectroscopy (SEM/EDX), physical match, drug identification, toxicology, serology, combined DNA index system (CODIS), DNA short tandem repeat (Y-STR), blood pattern, test fire, and comparison scope.

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Influence of Eyewitness Memory Factors on Plea Bargaining Decisions by Prosecution and Defense Attorneys in California, 2010-2011 (ICPSR 32181)

Released/updated on: 2012-07-31

Geographic coverage: United States, California

Time period: 2010-01-01--2011-01-01

The purpose of the study was to assess how the strength of eyewitness evidence affects plea bargaining decisions by prosecutors and defense attorneys. Surveys were administered to 93 defense attorneys and 46 prosecutors from matched counties in California. On the questionnaire, each participant was asked four background questions and read four versions of a crime scenario in which two specific eyewitness factors -- (a) same- versus cross-race identification and (b) prior contact or not -- were experimentally manipulated in a factorial design. The scenarios described a store robbery in which identification by one eyewitness was the only evidence against the defendant. After reading each scenario, attorneys were asked to respond to five questions in light of the facts presented. The study contains 28 variables including background data on the study participants and responses to questions relating to four crime scenarios that differ in terms of the details of the eyewitness evidence.

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Injury Evidence, Forensic Evidence and the Prosecution of Sexual Assault, United States, 2005-2011 (ICPSR 36608)

Released/updated on: 2018-04-23

Geographic coverage: United States

Time period: 2005-01-01--2011-01-01

This project explored the use and impact of injury evidence and biological evidence through a study of the role of these forms of evidence in prosecuting sexual assault in an urban district attorney's office in a metropolitan area in the eastern United States. The research questions addressed in this summary overview were as follows:

How frequent were different forms of injury evidence and biological evidence in the sample?
Is the presence of injury evidence and biological evidence correlated with the presence of other forms of evidence?
Which types of cases and case circumstances are more likely to yield injury evidence and biological evidence?
Do the presence of injury evidence and biological evidence predict criminal justice outcomes, taking into account the effects of other predictors?
In what ways do prosecutors use injury evidence and biological evidence and what is their appraisal of their impact on case outcomes?

The collection contains 1 SPSS data file, DataArchiveFile_InjuryEvidenceForensicEvidenceandthe ProsecutionofSexualAssault4-7-17.sav (n=257; 417 variables).

The qualitative data files were excluded from deposit with ICPSR and are not available as part of this data collection at this time.

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Jurors' Judgments About Forensic Identification Evidence, Arizona, 2011-2014 (ICPSR 36169)

Released/updated on: 2021-08-31

Geographic coverage: United States, Arizona

This data file describes three different experiments that were designed to examine how differences in the way forensic scientific evidence is communicated affects jurors.

In each experiment, participants consisted of jury-eligible community members in Maricopa County, Arizona. Groups of participants attended a research session in which they were shown a 35-40-minute videotapes of one of two mock criminal trials (one, a rape case, centers around bitemark evidence, and the other, an attempted murder, centers around fingerprint evidence). Within each trial the content of a forensic scientist's testimony was manipulated. These manipulations involved: 1) whether the technique used by the forensic scientist was "high tech" or "low tech," 2) the amount of experience possessed by the forensic scientist, 3) whether the technique used by the forensic scientist had been scientifically validated, 4) whether the forensic scientist conceded that an error was possible, and 5) whether any exculpatory evidence was present at the crime scene.

Immediately following the trial, each individual participants completed a questionnaire in which they gave their individual impressions of the strength of the case. Following that, the group of participant would deliberate and attempt to reach a unanimous verdict. Finally, each individual participant completed an additional questionnaire that again measured perceptions of the case along with individual difference measures and demographics.

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National Prosecutors Survey, 1990 (ICPSR 9579)

Released/updated on: 2005-11-04

Geographic coverage: United States

Time period: 1988-01-01--1990-01-01

This survey queried chief prosecuting attorneys of state prosecutorial districts (district attorneys, commonwealth attorneys, etc.) about the prosecution of felony cases within their jurisdictions during 1989-1990. Questions regarding the prefiling, filing, and pretrial stages of felony prosecution asked about policies limiting the time for plea negotiations, the role of the grand jury, how felony cases were screened, and the amount of time that usually elapsed before the prosecutor was notified of persons arrested for a felony. Prosecutors were also asked to report the percentage of court case filings by grand jury indictment, by information following a preliminary hearing, or by other means, and the percentage of felony cases processed by a court of general jurisdiction, a felony court, or other court(s). The trial stage of felony prosecution was covered by questions about the conduct of voir dire examination of prospective jurors, limits on time allowed to commence trial, the number of permitted peremptory challenges, who was responsible for notifying government witnesses to appear in court, whether the prosecution had the right to request a jury trial, whether the jurisdiction's felony court discouraged motions on trial date that would delay trial, and whether the felony court normally granted a continuance on trial date to permit additional time for plea negotiations. Questions on felony sentencing and appeals asked whether the prosecutor was usually present at felony sentence proceedings, whether the judge usually ordered a presentence report, whether victim information was requested or provided by the court, whether the prosecutor normally recommended a type or duration of sentence to be imposed, whether police, victims, or witnesses were notified of the disposition of felony cases, whether the prosecutor was involved in various types of appellate work, and whether the prosecutor had any right of appeal from rulings on motions, from sentences, and from determination of guilt or innocence. General information gathered by the survey includes the number of jurisdictions contained in the prosecutorial district, the number of attorneys and investigators employed in the sampled jurisdiction and in the prosecutorial district as a whole, the length of the prosecutor's term of office, the number of law enforcement agencies that brought arrests into the jurisdiction's court, how much of the prosecutor's felony caseload was assigned on a vertical basis, the kinds of nonfelony matters the prosecutor had responsibility for or jurisdiction over (e.g., family and domestic relations, mental commitments, environmental protection, traffic, etc.), whether the office of prosecutor was an elective position, and whether it was a full- or part-time position. Other general items include whether any felony defendants were provided an attorney on the grounds of indigency, whether, in criminal cases involving both state and federal jurisdiction, the prosecutor would ordinarily be cross-designated to represent the prosecutor in both courts, whether the prosecutor's office contained a "career criminal" unit, whether the state's attorney general was entitled to try cases in the jurisdiction's felony court, which types of criminal history data normally were of practical value in felony prosecution, and who supervised the probationer in most cases of adult felons sentenced to probation.

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National Prosecutors Survey, 1992 (ICPSR 6273)

Released/updated on: 2005-11-04

Geographic coverage: United States

Time period: 1991-07-01--1992-06-30

This survey queried chief prosecuting attorneys of state prosecutorial districts (district attorneys, commonwealth attorneys, etc.) about the prosecution of felony cases within their jurisdictions during 1991 and 1992. Some items included in an earlier survey, NATIONAL PROSECUTORS SURVEY, 1990 (ICPSR 9579), were repeated, covering topics such as new methods of prosecution, new kinds of evidence, use of criminal history data, general workload statistics, funding, plea negotiations, sentencing of intermediate sanctions, relationships with victims and other persons aiding prosecution, criminal defense of indigents, and the use of lower courts and grand juries. New areas of concern in 1992 included staffing, turnover, recruitment, new kinds of felonies, problem cases, scientific evidence, computerization, staff training, drug testing, and the personal risks associated with the role of prosecutor. Demographic data include sex, race, and ethnic composition of current staff members.

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National Prosecutors Survey, 1994 (ICPSR 6785)

Released/updated on: 2005-11-04

Geographic coverage: United States

Time period: 1994-01-01--1994-12-31

The National Survey of Prosecutors is a biennial survey of chief prosecutors in state court systems. A chief prosecutor is an official, usually locally elected and typically with the title of district attorney or county attorney, who is in charge of a prosecutorial district made up of one or more counties, and who conducts or supervises the prosecution of felony cases in a state court system. Prosecutors in courts of limited jurisdiction, such as municipal prosecutors, were not included in the survey. The survey's purpose was to obtain detailed descriptive information on prosecutors' offices, as well as information on their policies and practices. The data collection instrument was based on questions that were included in the NATIONAL PROSECUTORS SURVEY, 1992 (ICPSR 6273), and also added queries on topics of current concern, including: cross-designation of state prosecutors to try cases in federal court, juvenile transfers to criminal court, personal liability insurance for prosecutors, and involvement with community-based drug abuse programs. Variables include whether certain categories of felony prosecution, such as gangs, hate crimes, domestic violence, stalking, fraud, or child abuse or abduction were handled, whether DNA evidence, videotape, expert or child witnesses, polygraph tests, or wiretap evidence were used in trials, types of intermediate sanctions used, including house arrest, electronic monitoring, work release, substance abuse rehabilitation or therapy, community service, and fines or restitution, information on problem cases, personal risks associated with the role of the prosecutor, civil actions against prosecutors, criminal defense of indigent offenders, staffing, workload, funding, whether the defendant's criminal history was used in trials, juvenile matters, relationships with victims and other persons aiding prosecution, computerization, and community leadership. The unit of analysis is the district office.

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National Prosecutors Survey, 1996 (ICPSR 2433)

Released/updated on: 2005-11-04

Geographic coverage: United States

Time period: 1996-01-01--1996-12-31

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National Prosecutors Survey, 2005 (ICPSR 4600)

Released/updated on: 2007-02-23

Geographic coverage: United States

Time period: 2005-01-01--2005-12-31

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National Prosecutors Survey [Census], 2001 (ICPSR 3418)

Released/updated on: 2005-11-04

Geographic coverage: United States

The National Survey of Prosecutors is a survey of chief prosecutors in state court systems. It was previously conducted in 1990, 1992, 1994, and 1996 (ICPSR 9579, 6273, 6785, 2433 respectively). For 2001, instead of a survey of chief prosecutors, a census of all 2,341 chief prosecutors who handled felony cases in state courts of general jurisdiction was conducted. A chief prosecutor is an official, usually locally elected and typically with the title of district attorney or county attorney, who is in charge of a prosecutorial district made up of one or more counties, and who conducts or supervises the prosecution of felony cases in a state court system. Prosecutors in courts of limited jurisdiction, such as municipal prosecutors, were not included in the survey. The census' purpose was to obtain detailed descriptive information on prosecutors' offices, as well as information on their policies and practices. Variables cover staffing, funding, special categories of felony prosecutions, caseload, juvenile matters, work-related threats or assaults, the use of DNA evidence, and community-related activities, such as involvement in neighborhood associations. The unit of analysis is the district office.

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National Prosecutors Survey [Census], 2007 (ICPSR 33202)

Released/updated on: 2012-05-14

Geographic coverage: United States

Time period: 2007-01-01--2007-12-31

The 2007 Census of State Court Prosecutors marked the second BJS survey of all prosecutors' offices in the United States. The first census, conducted in 2001, included the 2,341 offices in operation at that time. The second census included the 2,330 state court prosecutors' offices operating in 2007. Neither census included offices of municipal attorneys or county attorneys, who primarily operate in courts of limited jurisdiction. State court prosecutors serve in the executive branch of state governments and handle felony cases in state courts of general jurisdiction. By law, these prosecutors are afforded broad discretion in determining who is charged with an offense and whether a case goes to trial. The chief prosecutor, also referred to as the district attorney, county attorney, commonwealth attorney, or state's attorney, represents the state in criminal cases and is answerable to the public as an elected or appointed public official. The Office of the United States Attorney for the District of Columbia is the only federal prosecutor included in the census. This unique office is responsible for prosecution of serious local crimes committed in the District and also for prosecution of federal cases, whether criminal or civil.

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National Survey of Eyewitness Identification Procedure in Law Enforcement Agencies, 1994-2012 (ICPSR 34274)

Released/updated on: 2014-03-07

Geographic coverage: United States

Time period: 1994-01-01--2012-01-01

The data results from a study conducted by the Police Executive Research Forum (PERF) designed to obtain the first nationwide assessment of the state of the criminal justice field regarding eyewitness identification procedures used by law enforcement agencies. PERF designed and conducted a survey of 619 police departments across the United States. The study focused on the departments training and policy when conducting eyewitness identification; particularly the study examined the use of "blind" administrators and the use of simultaneous or sequential presentation to the witness. The number of lineup members, witness instructions, police training, number of witness viewings and recording of the witness statements were also examined. A pilot test of the survey was conducted prior to the study.

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Nature and Patterns of Homicide in Eight American Cities, 1978 (ICPSR 8936)

Released/updated on: 2005-11-04

Geographic coverage: United States, Chicago, Tennessee, California, New Jersey, Pennsylvania, Illinois, Texas, Missouri, Newark, Memphis, Dallas, St. Louis, Philadelphia

This dataset contains detailed information on homicides in eight United States cities: Philadelphia, Newark, Chicago, St. Louis, Memphis, Dallas, Oakland, and "Ashton" (a representative large western city). Detailed characteristics for each homicide victim include time and date of homicide, age, gender, race, place of birth, marital status, living arrangement, occupation, socioeconomic status (SES), employment status, method of assault, location where homicide occurred, relationship of victim to offender, circumstances surrounding death, precipitation or resistance of victim, physical evidence collected, victim's drug history, victim's prior criminal record, and number of offenders identified. Data on up to two offenders and three witnesses are also available and include the criminal history, justice system disposition, and age, sex, and race of each offender. Information on the age, sex, and race of each witness also was collected, as were data on witness type (police informant, child, eyewitness, etc.). Finally, information from the medical examiner's records including results of narcotics and blood alcohol tests of the victim are provided.

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Pilot Study of State and Federal Digital Evidence Laboratories, [United States], 2014 (ICPSR 37055)

Released/updated on: 2018-10-18

Geographic coverage: United States

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.

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Post-Conviction DNA Testing and Wrongful Conviction Data from Sexual Assault and Homicide Cases in Virginia, 1973-1988 (ICPSR 34306)

Released/updated on: 2013-08-29

Geographic coverage: United States, Virginia

Time period: 1973-01-01--1988-01-01

This study examined the results of new DNA testing of old physical evidence from 634 sexual assault and homicide cases resulting in 715 convictions that took place in Virginia between 1973 and 1988. The research team conducted a retrospective study using data collected from the Virginia Department of Forensic Science files, visits to three Virginia county courthouses, and the COUNTY STATISTICS FILE 1 (CO-STAT): [UNITED STATES] (ICPSR 8314) to estimate the rate at which defendants are wrongly convicted and to identify case attributes associated with such wrongful convictions.

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Prosecution and Defense Strategies in Domestic Violence Felonies in Iowa, 1989-1995 (ICPSR 2811)

Released/updated on: 2006-03-30

Geographic coverage: Iowa, United States

Time period: 1989-01-01--1995-01-01

This study consisted of an in-depth analysis of the trial strategies used by the prosecution and the defense in domestic violence-related felony cases. The research objectives of this study were (1) to catalog the evidentiary constraints in domestic violence-related cases -- specifically, the types of character evidence and prior acts of defendants allowed during trial, (2) to show how the prosecution presented its case in domestic violence trials by identifying the key prosecution themes and strategies, (3) to present the specific evidence used by the prosecution to prove the elements of a case, and (4) to describe the themes and strategies used by the defense to counter the prosecution's case. Researchers focused on the admission of evidence of other acts of violence, known as "context" evidence, which characterized the violent relationship between the defendant and victim. The design involved a qualitative analysis of felony trial transcripts in Iowa from 1989 to 1995, in which the defendant and victim were involved in a domestic relationship. Part 1, Coded Transcript Data, contains the coded themes from the text analysis program. Background information was gathered on the length and type of relationship at the time of the incident, and the substance abuse and criminal histories of the defendant and the victim. Incident variables include current case charges, type of trial, description of physical injuries, whether hospitalization was required, type of weapon used, and whether the defendant or the victim owned a firearm. Other variables describe prosecution and defense strategies regarding evidence, identity, credibility, the nature of the relationship between the defendant and the victim, the intentions of the defendant, and how the police handled the case. Demographic variables include the race of the defendant and the ages of the defendant and the victim. Parts 2-40 consist of the actual court transcripts.

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The Role and Impact of Forensic Evidence on the Criminal Justice System, 2004-2008 [United States] (ICPSR 33462)

Released/updated on: 2017-03-30

Geographic coverage: San Diego, United States, Colorado, Denver, California, Florida, Miami

Time period: 2004-01-01--2006-01-01, 2005-01-01--2008-01-01

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.

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Search and Seizure Data, 1963 (ICPSR 7539)

Released/updated on: 1992-02-16

Time period: 1960-01-01--1963-01-01

This data collection contains information gathered about search and seizure policies and practices in a 1963 survey administered to one police chief, prosecutor, trial court judge, defense attorney, and American Civil Liberties Union (ACLU) official in each of the 50 states. Respondents answered questions about the practices of various criminal justice decision-makers in the handling of search and seizure evidence since the 1961 Supreme Court decision requiring all states to exclude illegally seized evidence from courtroom proceedings. Questions were also asked concerning the knowledge and values of the respondents, and the use of civil and legal action to deter illegal searches. The file also contains non-survey demographic data about the characteristics of each state.

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Sexual Assault Kit Backlog Study, Los Angeles, California, 1982-2010 (ICPSR 33841)

Released/updated on: 2013-11-20

Geographic coverage: United States, Los Angeles, California

Time period: 1982-01-01--2010-01-01

The study addressed the growing problem of untested sexual assault kits that have been collected and stored in law enforcement agencies' storage facilities and forensic laboratories throughout the nation. Project researchers randomly collected a 20 percent sample of the 10,895 backlogged sexual assault cases (cases with untested sexual assault kits) at the Los Angeles Police Department (LAPD) and Los Angeles Sherriff's Department (LASD) to be tested and to evaluate the scientific results achieved by private testing laboratories. After sorting through files and eliminating many due to time constraints, case count fluctuations throughout the course of the data collection, the inability to locate every case file, and removing cases due to the suspects' age, the researchers collected and coded sexual assault case information on 1,948 backlogged cases from 1982 to 2009. Data were also collected on 371 non-backlogged sexual assault cases with sexual assault kits that were tested between January 1, 2009 and August 1, 2010. Data collection focused on the respective agencies' crime laboratory files and the DNA reports submitted by outside private testing laboratories. Data collection tools for this project focused on key descriptive, investigative, critical event times/dates, physical evidence, and analytical tests performed on the evidence. Records yielded information on DNA profiles and related Combined DNA Index System (CODIS) submission activity. Criminal justice case disposition information was also collected on a total of 742 cases including a sample of 371 backlogged cases and the 371 non-backlogged cases to examine the impact of evidence contained in sexual assault kits on criminal justice disposition outcomes. The resulting 2,319 case dataset, which is comprised of 1,948 backlogged cases and 371 non-backlogged cases, contains 377 variables relating to victim, suspect, and crime characteristics, laboratory information and testing results, CODIS information, and criminal justice dispositions.

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Testing the Efficacy of the SANE-SART Programs in Kansas, Massachusetts, and New Jersey, 1997-2001 (ICPSR 20341)

Released/updated on: 2008-10-01

Geographic coverage: United States, Massachusetts, Kansas, New Jersey

Time period: 1997-01-01--2001-01-01

The purpose of the study was to explore the impact of interventions by Sexual Assault Nurse Examiners/Sexual Assault Response Teams (SANE/SART) on the judicial process. The goal was to test the efficacy of SANE/SART programs as a tool in the criminal justice system. The American Prosecutors Research Institute and Boston College tested the hypotheses that SANE/SART exams increase arrest and prosecution rates. The researchers collected case information from SANE/SART, police, and prosecution files in three jurisdictions: Monmouth County (Freehold), New Jersey, Sedgwick County (Wichita), Kansas, and Suffolk County (Boston), Massachusetts. At each study site, the project team randomly selected up to 125 sexual assault cases in which there was a SANE or SART intervention and 125 cases in which there was no SANE/SART intervention from cases that were opened and closed between 1997 and 2001. Comparisons were sought between SANE/SART cases (both SANE only and SANE/SART combined) and non-SANE/SART cases to determine if the intervention predicted the likelihood of certain criminal justice system outcomes. These outcomes included identification/arrest of a suspect, the filing of charges, case disposition, type of penalty, and length of sentence. In addition, researchers collected information on a number of other variables that could impact or mitigate the effect of SANE/SART interventions and case outcomes. The researchers abstracted information from case files maintained by SANE programs, police incident/arrest reports, and prosecution files during intensive five-day site visits. Three standardized records abstraction forms were developed to collect data: (1) the incident form was designed to collect data from police reports and the prosecution files about the actual sexual assault, (2) the case abstraction form was designed to collect prosecution data and case outcome data from the prosecutors' case files, and (3) the SANE/SART data collection form collected information from the SANE/SART files about the SANE/SART intervention. Specific information regarding the evidence collected during the victim's exam, nature of the assault, evidence/forensic kits collected, victim's demeanor, weapon(s) used, number of assailants, and the victim/offender relationship were collected.

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Towards Commercialization: Preliminary Developmental Validation of a High Resolution Melt Curve Mixture Prediction Assay and SVM Tool, Virginia, 2020-2022 (ICPSR 39133)

Released/updated on: 2024-08-28

Geographic coverage: United States, Virginia

Time period: 2020-01-01--2022-01-01

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.

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Verification and Evaluation of a miRNA Panel for Body Fluid Identification Using DNA Extracts, United States, 2019-2021 (ICPSR 38391)

Released/updated on: 2024-05-29

Geographic coverage: United States

Time period: 2019-01-01--2021-12-31

Although human identification through DNA analysis has reached a level of maturity in the Forensic Science field with regards to the sophistication of the techniques and confidence in the results, the equally important question of body fluid identification has lagged behind, and could still be considered to be in a rudimentary state. Current crime scene and in-laboratory methods utilize detection methods that exploit the properties of each biological fluid (e.g. phenolphthalin or TMB testing for blood, amylase detection for saliva, and urease tests for urine), but validated confirmatory techniques are largely limited to microscopic methods (i.e. identification of spermatozoa) or immunological methods, as seen in the widely used immunochromatographic commercial tests for blood, semen, and other biological fluids.

Thus, while there is widespread confidence in the DNA profile generated, there is often significantly less assurance in the identity of the body fluid that the DNA profile was developed from. It is common during trials for attorneys to categorically accept the STR analysis, but probe the forensic scientist on the source of the DNA that generated the profile. Because of this dichotomy, significant efforts have been made over the past fifteen years in order to develop forensic serological techniques of a more discriminatory nature.

Of late, there has been some work in the forensic science field in regards to exploring microRNAs (miRNAs) for a molecular-based, forensic body fluid identification method. MiRNAs are small structures that are 19-23 nucleotides long and regulate cellular processes through interactions with mRNA by regulating gene expression through translational suppression or cleavage of a targeted mRNA. miRNAs are highly conserved among organisms, indicating their importance in regulating biological processes. As such, some miRNAs can be consistently expressed in all human tissues, and others can be tissue-specific Because of the potential for tissue specificity, their small size and consequent inherent stability, miRNAs have been the subject of recent research interest as a potential forensic body fluid identification technique. They are found in extracellular fluids, and thus the application of unique miRNAs for forensically relevant body fluids is a distinct possibility.