Public Safety Lab

With the support of the Global Institute of Advanced Study, the Public Safety Lab has been launched to apply the tools of data science and social science to the project of producing better public safety outcomes.

For example, many relatively minor offenses are easy to detect and interdict. Many more serious offenses are much harder to detect and interdict. As a consequence we may overpunish relatively minor offenses, and underpunish more serious offenses. The Public Safety Lab works with both jurisdictions and publicly accessible data to identify strategies that minimize both overpunishment and underpunishment.

The Public Safety Lab’s Jail Data Initiative focuses on the problem of overincarceration, which has received considerable attention of late. The focus of this attention, however, has largely been on state and federal prison systems. Often overlooked are local jails. In any given year, approximately 11 million Americans will be detained in a county jail, often because they lack the funds to post bail, or even because they lack the funds to pay their fines. Yet we know little about county jail practices, including which counties are systematically jailing defendants pre-trial and/or post-fine, and about the consequences of these practices. It is possible that longer periods of pre-trial detention, for example, actually increase recidivism, and/or escalate petty offending into more serious offending. Through the generous support of Arnold Ventures, our data science team is crawling daily county jail rosters and criminal case records in over 1,000 counties. Using these data we will be able both to identify counties that are systematically jailing defendants pre-trial and/or post-fine, and to estimate the impacts of these practices on recidivism.

The Public Safety Lab’s Prosecutorial Reform Initiative focuses on the vital role played by prosecutors in the criminal justice system. After an arrest, prosecutors have numerous choices to make regarding whether and how to pursue prosecution of an offense. In many jurisdictions, prosecutors use this discretion to pursue prosecutions of subfelony violations to the full extent of the criminal law. In these jurisdictions, cases involving subfelony offenses typically consume a large share of law enforcement, prosecutorial, and judicial resources. Yet it is unclear whether the aggressive prosecution of subfelony offenses actually reduces offender recidivism; the practice may actually result in increased recidivism, and/or the escalation of minor offending into more serious offending. Some prosecutors’ offices, however, are pursuing reforms that implement alternatives to prosecution, or that reduce charging, bail recommendation, and/or sentence recommendation practices for defined categories of subfelony offenses. Working with multiple district attorneys’ offices, we are investigating the impacts of these reforms on offender recidivism.

Descriptions of our other projects may be found on the lab’s website, www.publicsafetylab.org.

Project members:

Principal Investigator: Anna Harvey (NYU)

Amanda Agan (Rutgers)

Mike Cafarella (University of Michigan)

Chris Dawes (NYU)

Sanford Gordon (NYU)

Dean Knox (Princeton)

Jonathan Mummolo (Princeton)

Murat Mungan (George Mason University)

Daniel Neill (NYU)

Olga Russakovsky (Princeton)

Brandon Stewart (Princeton)

Hye Young You (NYU)