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PHILADELPHIA (March 11, 2020) – District Attorney Larry Krasner on Wednesday announced a private-public research collaboration aimed at studying the short- and long-term impacts of prosecutorial decision-making on individuals, families, and communities in Philadelphia.

The District Attorney’s Office (DAO) will collaborate with researchers at the University of Pennsylvania (Penn), with support from Arnold Ventures (AV) and the Chan Zuckerberg Initiative (CZI), to assess how policies and practices of administrations present and past have influenced incarceration rates, community safety, and other key criminal justice metrics.

The criminal legal system’s power to control people’s liberty, movement, wealth, and even time and manner of death is fearsome – and too often wielded with little to no accountability. Our movement to make the criminal legal system fair, just, and effective for every community demands a more transparent and accountable exercise of that power,” District Attorney Krasner said. Philadelphia voters elected me in historic numbers because they rightly demand that this enormous power be shared with the public. I am thankful to our partners – including Penn, Arnold Ventures, and CZI – for providing the Philadelphia District Attorney’s Office with financial and technical support for our effort to dismantle the black box’ model of prosecutors’ offices in order to build a more fair, just, and effective criminal legal system.”

The anticipated contributions to the three-year research collaboration break down as follows:

CZI: $3.5 million
AV: $3.5 million
Total funding: $7 million ($2.5M to Penn, $4.5M to DAO)

Research collaboration grant funding will support more than 12 new DAO positions over three years, and includes support of researchers and personnel based at Penn. The Penn research team will be led by Professor Greg Ridgeway, chair of the Department of Criminology, and Professor Aurélie Ouss, Jerry Lee Assistant Professor of Criminology.

Several Penn researchers will be embedded at the DAO so that they may more easily work with DAO personnel to understand the system and to validate DAO data. These individuals will be subject to the same strict laws and regulations governing information use and information sharing as all DAO employees. Other Penn researchers will not be embedded and will have access to de-identified information only. All Penn researchers will also be separately bound by the university’s privacy and data handling procedures and best practices, which are detailed here: https://​irb​.upenn​.edu/. AV and CZI may receive only aggregated data and reports regarding the research progress, and will not have access to any information about individual cases or people.

This research partnership builds on existing progress and brings together experts from across the field to deepen understanding of how prosecutor decisions ripple across communities in Philadelphia. Reports, analyses, and findings produced through this partnership will be used to help the DAO strengthen and expand a culture of decision-making informed by empirical evidence, rather than disproven assumptions about policies and practices that must be reformed.

Internally, the collaboration will be sited within the DAO DATA Lab, which in late 2019 released a first-of-its-kind public-facing dashboardfor the public to monitor the local justice system in real time.

We firmly believe that the only way to change the criminal justice system is to measure it: the size of the system, how cases move through the system, and how the system affects the lives of all Philadelphians,” DAO Director of Analytics Michael Hollander said. We are excited to bring transparency and accountability to the criminal justice system and to better understand how decisions made by our ADAs every day impact the long-term health and welfare of our city. Our partnership with Penn will allow us to bring smart, effective change to the criminal justice system in Philadelphia and support similar efforts throughout the country.”

This unprecedented research effort will help the Philadelphia DAO reduce the time it takes for policies to be studied and learned from, and position us to emerge as the most researchable prosecutor’s office in the country,” DAO DATA Lab Director Oren Gur, Ph.D., said. This type of project is possible because of the commitment of District Attorney Krasner to scientific inquiry, the deep desire among Philadelphians to be able to hold systems accountable, and the unique partnership between our office, AV, CZI, and Penn, which will support research, technological infrastructure, and accountability. We’re privileged to support the broader movement to reassess the role of prosecutors in this era of criminal justice reform.”

This three-year research collaboration will support DAO efforts to:

  • Better understand the connection between charging and sentencing decisions and outcomes such as recidivism and desistance, housing access, employment, and public safety in Philadelphia.
  • Test and assess the efficacy of approaches to prosecutorial decision-making via research analysis by the Penn team, which will lead the effort in accordance with the University’s data and privacy best practices and standards.
  • Share learnings from the partnership with the broader community of organizations committed to public safety and improving criminal justice outcomes.

Research and findings from this partnership will be published throughout the three-year term of the project.

Independent, external analysis of the impact of prosecutorial policies, like the independent, external analysis we hope to see from the University of Pennsylvania’s role in this partnership, could help movements for justice hold our criminal legal system accountable as we work to end mass incarceration,” said Hannah Sassaman, policy director at Movement Alliance Project (formerly Media Mobilizing Project). We look forward to seeing that analysis and continuing to work to wind down mass incarceration in Philadelphia.”

Larry Krasner committed to more transparency in the operations of the District Attorney’s Office, and this project is the next logical step in that process,” said Sara Mullen, associate director of the ACLU of Pennsylvania. The kind of data that will be provided will give the people of Philadelphia a clearer understanding of how the DA’s office functions, how it serves the community, and where it falls short. Public officials are accountable to the people, and we hope that this tool will create a culture of public accountability.” 


The Philadelphia District Attorney’s Office is the largest prosecutor’s office in Pennsylvania, and one of the largest in the nation. It serves the more than 1.5 million citizens of the City and County of Philadelphia, employing 600 lawyers, detectives, and support staff. The District Attorney’s Office is responsible for prosecution of approximately 40,000 criminal cases annually.