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Showing 1 – 8 of 8 results.
Curated

Effects of "United States vs. Leon" on Police Search Warrant Practices, 1984-1985 (ICPSR 9348)

Released/updated on: 2006-01-12
Geographic coverage: United States
This data collection examines the impact of the Supreme Court decision in "UNITED STATES VS. LEON" on police search warrant applications in seven jurisdictions. For this collection, which is one of the few data collections currently available for the study of warrant activities, data were gathered from search warrant applications filed during a three-month period before the Leon decision and three months after it. Each warrant application can be tracked through the criminal justice system to its disposition. The file contains variables on the contents of the warrant such as rank of applicant, specific area of search, offense type, material sought, basis of evidence, status of informants, and reference to good faith. Additional variables concern the results of the warrant application and include items such as materials seized, arrest made, cases charged by prosecutor, type of attorney, whether a motion to suppress the warrant was filed, outcomes of motions, appeal status, and number of arrestees.
Curated

Evaluating the Use of Iris Recognition Technology in Plumsted Township, New Jersey, 2002-2003 (ICPSR 4210)

Released/updated on: 2013-06-28
Geographic coverage: United States, New Jersey
Time period: 2002-10-01--2003-07-01
This study was conducted from October 2002 through July 2003 as a process and impact evaluation of iris recognition technology named T-PASS (Teacher-Parent Authorization Security System) used in three New Egypt schools in New Jersey. The research team observed the use of the iris scanners, both informally (Dataset 1) and formally (Dataset 2), using systematic social observation methods, collected "official" data on school visitation patterns (Dataset 3), and administered surveys to parents and teachers (Datasets 4-7). The various data collection methods were intended to shed light on two key issues: what was the experience of the schools in implementing iris recognition technology, and what was the overall impact of the technology. Specific variables included in the study are demographic variables on survey respondents (parents and teachers), perceptions of safety and problems in the schools and surrounding neighborhoods, and comparisons of the T-PASS system to alternative entry systems such as the buzzer and swipe card methods.
Curated

Homicide Investigations in Los Angeles, California: An Analysis of Solved and Unsolved Cases, 1990-2010 (ICPSR 39255)

Released/updated on: 2025-01-30
Geographic coverage: United States, Los Angeles, California
Time period: 1990-01-01--2010-01-01

In 2018 Justice and Security Strategies, Inc. (JSS) recieved funding from the National Institute of Justice (NIJ) to code and analyze detailed homicide data collected by the Los Angeles Police Department (LAPD). The data in this study were compiled from the LAPD's digitized homicide casefiles, or Murder Books, stored at the Homicide Library. These digitized casefiles included relevant information from the chronological log of detective activity, crime scene log, first responder statements and officer reports, incident history from the CAD and 911 tapes, Los Angeles Fire Department medical service report, death/autopsy report, suspect arrest report, evidence reports, follow-up reports, investigator final report, search warrants, crime scene sketches, crime scene notes, scientific evidence analysis, witness statements and notes, suspect interview notes, and case status information. A total of 4,111 Murder Books detailing homicides from four of 21 LAPD area stations in South Los Angeles between 1990 to 2010 were digitally scanned and preserved for posterity. Through a grant from the National Institute of Justice, JSS researchers 'tagged' the data to facilitate sharing these Murder Books among detectives in the South Bureau. These 'tags' also serve to encode features and outcomes from the Murder Book case files.

The data archived from this project consist of the digital database of the tagged Murder Books. There are two files included in this project. The victim file contains information about both the incident (obtainable from unique incident numbers) and information about the victim (victim number associated with each incident). The suspect file contains information about the suspects associated with each incident and can be linked to the original incident through the incident number.

Curated
Restricted

LAPD's TEAMS II: The Impact of a Police Integrity Early Intervention System, Los Angeles, California, 2000-2015 (ICPSR 36574)

Released/updated on: 2018-09-17
Geographic coverage: United States, Los Angeles, California
Time period: 2000-01-01--2015-01-01

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 research was an evaluation of the Los Angeles Police Department's (LAPD) Training Evaluation and Management System II (TEAMS II) Early Intervention System conducted by Justice and Security Strategies, Inc. TEAMS II was designed to identify officers at-risk for engaging in future problematic behavior. This system was mandated as part of the Consent Decree (Section II) that was formally entered into on June 15, 2001 between the U.S. Department of Justice and the LAPD. Justice and Security Strategies, Inc. research staff worked with the Information Technology Bureau to obtain and analyze TEAMS II data, conducted informal interviews with officers, sergeants, civilians, command staff, and technologists involved with TEAMS II, and worked with the TEAMS II contractors to examine and provide recommendations.

The data collection includes 3 Stata data files. The concentration analysis dataset (TEAMS-Concentration-Analysis-FINAL-v2.dta) with 143 variables for 15,710 cases, the regression-discontinuity dataset (TEAMS-Regression-Discontinuity-FINAL.dta) with 98 variables for 297,779 cases, and the time series dataset (TEAMS-Time-Series-FINAL.dta) with 43 variables for 192 cases. Demographic variables included as part of this data collection include officer age, gender, ethnicity, education level, and total number of officers employed by demographics.

Curated

Linking Theory to Practice: Examining Geospatial Predictive Policing, Denver, Colorado, 2013-2015 (ICPSR 37299)

Released/updated on: 2020-02-26
Geographic coverage: United States, Colorado, Denver
Time period: 2013-01-01--2015-12-31

This research sought to examine and evaluate geospatial predictive policing models across the United States. The purpose of this applied research is three-fold: (1) to link theory and appropriate data/measures to the practice of predictive policing; (2) to determine the accuracy of various predictive policing algorithms to include traditional hotspot analyses, regression-based analyses, and data-mining algorithms; and (3) to determine how algorithms perform in a predictive policing process.

Specifically, the research project sought to answer questions such as:

  • What are the underlying criminological theories that guide the development of the algorithms and subsequent strategies?
  • What data are needed in what capacity and when?
  • What types of software and hardware are useful and necessary?
  • How does predictive policing "work" in the field? What is the practical utility of it?
  • How do we measure the impacts of predictive policing?

The project's primary phases included: (1) employing report card strategies to analyze, review and evaluate available data sources, software and analytic methods; (2) reviewing the literature on predictive tools and predictive strategies; and (3) evaluating how police agencies and researchers tested predictive algorithms and predictive policing processes.

Curated

Modern Policing and the Control of Illegal Drugs: Testing New Strategies in Oakland, California, and Birmingham, Alabama, 1987-1989 (ICPSR 9962)

Released/updated on: 2005-11-04
Geographic coverage: California, Alabama, Oakland, Birmingham
Time period: 1987-01-01--1989-01-01
These data were collected in Oakland, California, and Birmingham, Alabama, to examine the effectiveness of alternative drug enforcement strategies. A further objective was to compare the relative effectiveness of strategies drawn from professional- versus community-oriented models of policing. The professional model emphasizes police responsibility for crime control, whereas the community model stresses the importance of a police-citizen partnership in crime control. At each site, experimental treatments were applied to selected police beats. The Oakland Police Department implemented a high-visibility enforcement effort consisting of undercover buy-bust operations, aggressive patrols, and motor vehicle stops, while the Birmingham Police Department engaged in somewhat less visible buy-busts and sting operations. Both departments attempted a community-oriented approach involving door-to-door contacts with residents. In Oakland, four beats were studied: one beat used a special drug enforcement unit, another used a door-to-door community policing strategy, a third used a combination of these approaches, and the fourth beat served as a control group. In Birmingham, three beats were chosen: Drug enforcement was conducted by the narcotics unit in one beat, door-to-door policing, as in Oakland, was used in another beat, and a police substation was established in the third beat. To evaluate the effectiveness of these alternative strategies, data were collected from three sources. First, a panel survey was administered in two waves on a pre-test/post-test basis. The panel survey data addressed the ways in which citizens' perceptions of drug activity, crime problems, neighborhood safety, and police service were affected by the various policing strategies. Second, structured observations of police and citizen encounters were made in Oakland during the periods the treatments were in effect. Observers trained by the researchers recorded information regarding the roles and behaviors of police and citizens as well as police compliance with the experiment's procedures. And third, to assess the impact of the alternative strategies on crime rates, reported crime data were collected for time periods before and during the experimental treatment periods, both in the targeted beats and city-wide.
Curated

Testing and Evaluating Body Worn Video Technology in the Los Angeles Police Department, California, 2012-2018 (ICPSR 37467)

Released/updated on: 2021-04-28
Geographic coverage: United States, Los Angeles, California
Time period: 2015-08-01--2015-09-01, 2016-06-01--2016-08-01, 2012-01-01--2017-01-01

This research sought to evaluate the implementation of body worn cameras (BWCs) in the Los Angeles Police Department (LAPD). Researchers employed three strategies to evaluate the impact of BWCs in the department: 1) two-wave officer surveys about BWCs, 2) two-wave Systematic Social Observations (SSOs) of citizen interactions from officer ride-alongs, and 3) a time series analysis of existing LAPD data of use of force and complaint data.

The officer surveys were conducted in the Mission and Newton divisions of the LAPD before and after BWCs were implemented. The survey instrument was designed to measure perceptions of BWCs across a variety of domains and took approximately 20 minutes to complete. Researchers attended roll calls for all shifts and units to request officer participation and administered the surveys on tablets using the Qualtrics software. The pre-deployment survey was administered in both divisions August and September 2015. The post-deployment surveys were conducted with a subset of officers who participated in the pre-deployment surveys during a two-week period in the summer of 2016, approximately nine months following the initial rollout of BWCs.

The SSO data was collected in the Mission and Newton divisions prior to and following BWC implementation. The pre-administration SSOs were conducted in August and September 2015 and the post-administration SSOs were conducted in June and August, 2016. Trained observers spent 725 hours riding with and collecting observational data on the encounters between officers and citizens using tablets to perform field coding using Qualtrics software. A total of 124 rides (71 from Wave I and 53 from Wave II) were completed between both Newton and Mission Divisions. These observations included 514 encounters and involved coding the interactions of 1,022 citizens, 555 of which were deemed to be citizens who had full contact, which was defined as a minute or more of face-time or at least three verbal exchanges.

Patrol officers (including special units) for ride-alongs were selected from a master list of officers scheduled to work each day and shift throughout the observation period. Up to five officers within each shift were randomly identified as potential participants for observation from this master list and observers would select the first available officer from this list. For each six-hour observation period, or approximately one-half of a shift, the research staff observed the interactions between the assigned officer, his or her partner, and any citizens he or she encountered. In Wave 2, SSOs were conducted with the same officers from Wave 1.

The time series data were obtained from the LAPD use of force and complaint databases for each of the 21 separate patrol divisions, a metropolitan patrol division, and four traffic divisions of the LAPD. These data cover the time period where BWC were implemented throughout the LAPD on a staggered basis by division from 2015 to 2018. The LAPD operates using four-week deployment periods (DPs), and there are approximately 13 deployment periods per year. These data span the period of the beginning of 2012 through the 2017 DP 12. These data were aggregated to counts by deployment period based on the date of the originating incident. The LAPD collects detailed information about each application of force by an officer within an encounter. For this reason, separate use of force counts are based on incidents, officers, and use of force applications. Similarly, the LAPD also collects information on each allegation for each officer within a complaint and public complaint counts are based on incidents, officers, and allegations.

Curated

Violence Against Police: Baltimore County, Maryland, 1984-1986 (ICPSR 9347)

Released/updated on: 1997-09-11
Geographic coverage: United States, Maryland
Time period: 1984-01-01--1987-03-31
This data collection examines individual and situational characteristics of nonfatal assaults on police officers in the Baltimore County Police Department. In the assault data, variables include: (1) information on the officer such as age, race, sex, height, weight, education, rank, assignment, years of experience, weapon, and injury sustained, (2) information on the offender(s) such as age, race, sex, height, weight, weapon, injury sustained, and arrest status, and (3) information on the actual situation and incident itself, such as type of call anticipated, type of call encountered, type of location, numbers of persons present (by role, e.g., assaulter, nonassaulter, complainant, etc.), type of initial officer action, actions of suspect before assault, sobriety/drug use by suspects, and final disposition. The calls for service data were collected to provide an indication of the frequency of various types of calls. In these data, variables include time of call, initial call category, disposition code, and sheet ID.
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