BERKELEY, Calif. – A new set of interactive data tools is providing Californians with an unprecedented look inside the state’s prison system. Developed by the California Policy Lab in partnership with the state’s Committee on the Revision of the Penal Code, the California Prison Population Data Dashboards make ten years of state prison data accessible to anyone online.

The dashboards, located at www.californiaprisondata.org, enable users to explore trends in California’s prison population by various factors, including race, gender, age, offense type, and county of conviction.

According to committee chair Michael Romano, the tool represents the first time that detailed data about who goes to prison, for what crimes, and for how long, has been made readily available to the public.

A New Era of Transparency

Researchers say the project reflects years of effort to make criminal justice data more accessible and transparent. The dashboard data is directly drawn from the California Department of Corrections and Rehabilitation (CDCR) and will be updated twice a year to include new information on admissions, releases, and the current population.

Before this release, researchers and journalists often had to file public records requests or use specialized software to obtain similar data.

Features and Insights

The dashboards contain three major interactive sections: current population, admissions since 2015, and releases since 2015. Users can filter data to view sentence lengths, offense categories, demographic breakdowns, and details about sentence enhancements.

A Collaborative Effort

Mia Bird, Assistant Professor of Public Policy at UC Berkeley and one of the project’s lead researchers, said the CDCR has supported the project by providing data directly to the committee under a special data-sharing arrangement authorized by the governor’s office. Bird said CDCR has been an enormous source of support.

“They have been fantastic,” she said.

This is a special data-sharing arrangement because the committee is tasked by the governor’s office to provide research to the legislature. It’s a streamlined process compared to the normal research request process. They have been incredibly generous with their time as we try to match their business rules, and it’s been a really productive collaborative process.”

Numbers Help When Evaluating Reforms

Bird’s team is already using the data to assess the real-world effects of reforms such as Proposition 57, which expanded parole opportunities for people convicted of nonviolent crimes. Bird said her team is studying how the measure has affected recidivism and overall prison populations.

Future Work

The California Policy Lab and the Committee on the Revision of the Penal Code are also collaborating with Stanford Law School to develop a complementary dataset that will enable even deeper analysis.

The dashboards are live and available to the public. Bird encouraged users to explore the site and share feedback to help improve future versions.

For more information or to explore the data, visit www.californiaprisondata.org.