Downloaded the data from the Williamette University website.
Downloaded the county and state level data on December 6, 2023.
Downloaded the municipality level data on December 7, 2023.
Law Enforcement Management and Administrative Statistics (LEMAS)
Downloaded the LEMAS data from the Inter-university Consortium for Political and Social Research (ICPSR) website on February 8, 2024.
Law Enforcement Officers Killed in Action (LEOKA)
Downloaded “Jacob Kaplan’s Concatenated Files: Uniform Crime Reporting Program Data: Law Enforcement Officers Killed and Assaulted (LEOKA)” from the Inter-university Consortium for Political and Social Research (ICPSR) website on September 14, 2023.
Montgomery County Open Data
Downloaded the data from the dataMontgomery website on December 4, 2023.
National Incident-Based Reporting System (NIBRS)
Downloaded the 2022 data from the Inter-university Consortium for Political and Social Research (ICPSR) website on April 26, 2024.
Prince George’s County Open Data
Downloaded the data from the Prince George’s County Open Data Portal website on December 4, 2023.
Recidivism of Prisoners Released in 24 States in 2008: A 10-Year Follow-Up Period (2008–2018)
Downloaded the data from the Bureau of Justice Statistics (BJS) website on April 26, 2024.
Recidivism of Prisoners Released in 34 States in 2012: A 5-Year Follow-Up Period (2012–2017)
Downloaded the data from the Bureau of Justice Statistics (BJS) website on April 26, 2024.
Survey of Inmates in State and Federal Correctional Facilities (SISFCF)
Downloaded the 2004 data from the Inter-university Consortium for Political and Social Research (ICPSR) website on April 26, 2024.
Survey of State Criminal History Information Systems (SSCHIS)
Downloaded the 2020 full report from the Bureau of Justice Statistics (BJS) website on April 26, 2024.
Uniform Crime Report (UCR)
UCR data encompassing the years 1936-1959 provided by Bryan Stuart at the Federal Reserve Bank of Philadelphia on March 8, 2023.
Contains data from 1936-1959 for the District, 1940-1959 for Alexandria City, and 1941-1959 for Arlington County.
Downloaded “Jacob Kaplan’s Concatenated Files: Uniform Crime Reporting Program Data: Offenses Known and Clearances by Arrest” from the Inter-university Consortium for Political and Social Research (ICPSR) website on August 1, 2023 for years 1960-2021.
United States Sentencing Commission Federal Sentencing Statistics Reports
Obtained the data from the United States Sentencing Commission website on December 6, 2023.
For each year, selected DC District, Maryland, Virginia, and West Virginia.
US Bureau of Labor Statistics Occupational Employment and Wage Statistics (BLS OEWS)
Downloaded data from the U.S. Bureau of Labor Statistics Occupational Employment and Wage Statistics website at the metropolitan and nonmetropolitan area level from May of each year from 1999 through 2022 on February 1, 2024.
US Census Bureau’s County Intercensal Datasets
Downloaded “The 1970 to 1979 Population Estimates of the U.S., States, and Counties” data from the United States Census Bureau website on December 11, 2023.
County level data.
US Census Bureau’s County Intercensal Tables
Downloaded the “County Totals” data from the United States Census Bureau website on December 11, 2023.
County level data.
US Census Bureau’s County Population Totals and Components of Change
Downloaded the “Annual Estimates of the Resident Population for Counties” data for District of Columbia, Maryland, Virginia, and West Virginia, from the United States Census Bureau website on December 11, 2023.
County level data.
US Census Bureau’s Population Estimates Program (PEP)
Obtained the PEP data using the API provided on the United States Census Bureau website on December 11, 2023.
This was accomplished using the R package “RJSONIO”.
County and state level data.
US Census Bureau’s State and County Intercensal Tables
Downloaded the “Time Series of Intercensal Estimates for Counties by State” data for District of Columbia, Maryland, Virginia, and West Virginia, from the United States Census Bureau website on December 11, 2023.