Keynote: Megan T. Stevenson

Algorithmic Risk Assessment in the Hands of Humans

Abstract: We evaluate the impacts of adopting algorithmic risk assessments as an aid to judicial discretion in felony sentencing. We find that judges' decisions are influenced by the risk score, leading to longer sentences for defendants with higher scores and shorter sentences for those with lower scores. However, despite explicit instructions that risk assessment was supposed to lower prison populations, there was no net reduction in incarceration. Nor do we detect any public safety benefits from its use. We document racial disparities both in the risk score and in its application: judges are more likely to follow the leniency recommendations associated with the risk score for White defendants than for Black. However, sentencing in Virginia was already quite racially disparate and risk assessment use neither exacerbated nor ameliorated the differences. Risk assessment did, however, increase relative sentences for young defendants. We explore several theories around human-machine interaction to better understand our results: conflicting objectives, learning through use, adopters versus nonadopters, and ineffective use of information. Paper the presentation is based on.

Megan Stevenson is an economist and criminal justice scholar. She has conducted empirical research in various areas of criminal justice reform, including bail, algorithmic risk assessment, misdemeanors and juvenile justice. Her research on bail was cited extensively in a landmark federal civil rights decision, O'Donnell v. Harris, and has received widespread media coverage. She was the 2019 winner of the Oliver E Williamson prize for best article, chosen among all articles published in the Journal of Law, Economics, & Organization within the previous three years. She publishes in both law reviews and economic journals, including the Stanford Law Review, the Washington University Law Review, the Minnesota Law Review, the Boston College Law Review, the Boston University Law Review, the Review of Economics and Statistics, and the Journal of Law, Economics, & Organization.

Prior to joining the law faculty at UVA, Stevenson was an assistant professor of law at George Mason University's Antonin Scalia Law School (2017-2020) and a fellow at the Quattrone Center for the Fair Administration of Justice at the University of Pennsylvania Law School (2015-17). She holds a Ph.D. in agricultural and resource economics from the University of California, Berkeley. Her teaching areas include criminal law, evidence-based criminal justice reform, statistics for lawyers and economics for lawyers.