A Guide to International and U.S. Statistics Sources: Crime Statistics

Corrections, Courts & Sentencing, Crime Type, Employment & Expenditure, Federal, Law Enforcement, and Victims.

"DPIC produces groundbreaking reports on issues such as arbitrariness, costs, innocence, and racial disparities. DPIC also releases an annual year-end report highlighting significant developments and trends." [About the DIPC]

The Gun Violence Archive is an online archive of gun violence incidents collected from over 2,000 media, law enforcement, government and commercial sources daily in an effort to provide near-real time data about the results of gun violence. GVA in an independent data collection and research group with no affiliation with any advocacy organization.
Data back to 2014.
See also: Tool from The Guardian which maps 2015 data down to the tract level.

This site may be blocked by malware detectors for phishing. You may not want to use it, but I'm leaving it here for now.
"Mass shootings, detailed. The Violence Project’s Mass Shooter Database contains extensive details about public mass shootings in the US and their perpetrators, weapons, and victims, with a goal of “finding pathways to prevention.” The database, funded by a National Institute of Justice grant, covers 170+ shootings between 1966 and early 2020. Examples of the variables include: the perpetrator’s employment status, known prejudices, and experience with mental illness; the victims’ relationship to the perpetrator and estimated years of life they lost; and the firearms’ make, model, and method of acquisition." [Description from Jeremy Singer-Vine's "Data is Plural" newsletter.

A portal to a variety of US criminal justice statistics and publications. See: Open Data

Analyzing traffic stop data from across the country.

Transactional Records Access Clearinghouse (TRAC), an organization associated with Syracuse University that gathers, performs research, and distributes data about the activities of the federal enforcement and regulatory agencies. U.S. Customs Service, Federal Bureau of Investigation (FBI), Dept. of Homeland Security (DHS), Internal Revenue Service (IRS), Drug Enforcement Agency (DEA), the Bureau of Alcohol, Tobacco and Firearms (ATF), and the Immigration and Nationalization Serivce (INS).

The Office of Research and Data collects data from documents submitted by the courts in each case in which a defendant is sentenced. From that data, the Commission prepares and disseminates public reports on a wide variety of sentencing issues.

Note: Latest statistics are from 2021. Jail admissions ~ Jail incarceration ~ Pretrial jail incarceration ~ Prison incarceration for counties and states.

"As part of a new initiative, the Sunlight Foundation has begun amassing an inventory of public and privately-produced criminal justice data.
The spreadsheet on this page is a work in progress ..."