The CJARS data platform is built on individual-level records created in the normal course of the criminal justice system, such as arrest reports, court case processing, and correctional records. These data are harmonized into a common national format in order to support tracking individuals over the sequence of their criminal justice events and across jurisdictional boundaries. As a resources for those interested in the projects and its data infrastructure, please review the CJARS data documentation for more information on the project, its data holdings, and its data harmonization process.
The records are collected through multiple channels: accessing publicly available databases online, purchasing public information through Freedom of Information Act mechanisms, and engaging agencies directly with data use agreements (DUAs).
CJARS currently hosts data from a number of states and local jurisdictions, some with decades of comprehensive historical archives. At the state level, these are typically correctional population and court records. Data on arrests, bookings, and jail sentences usually must be collected at the substate level.
Currently, CJARS holds over 1.7 billion lines of raw data, with the largest portion of data coming from data use agreements.