Joan Petersilia was an empirical researcher who pointed to clear-eyed data rather than emotions in a field often dominated by public fear and sentiment.

Over the course of a career spanning 40 years she not only published a wealth of groundbreaking research but also gained the trust of policymakers who eagerly sought her help in solving some of the toughest challenges facing America’s bloated and complicated criminal justice system. She was on speed-dial for two California governors and countless state, county, and city officials—advising on the implementation of California’s innovative “realignment” program to alleviate the state’s extreme prison overcrowding, seeking ways to end the revolving door back to prison, and more. Her work was ultimately recognized in 2014 when she received the Stockholm Prize in Criminology, the Nobel Prize of the field.

Petersilia, the Adelbert H. Sweet Professor of Law, Emerita, at Stanford passed away on Monday, September 23, 2019 from ovarian cancer one year after retiring for health reasons. She was 68. She is survived by her husband Steve Thomas, two sons Jeff and Kyle Petersilia, two sisters Margaret Ann Johnson and Jeanne Ramme Sydenstricker, several nieces and nephews—and hundreds of colleagues and former students who counted her not only as a mentor and collaborator but as a friend.

“The word ‘transformational’ gets overused, but it applies perfectly to Joan’s role at Stanford. At a time when mass incarceration had become the key civil rights and social justice issue of our time, she was already the nation’s leading expert on sentencing and corrections.  So when we persuaded this great non-lawyer to make the leap to a law school, she brought with her profound expertise and deep wisdom on a subject so crucial to our law students and to the faculty as well,” says Robert Weisberg, JD ’79, the Edwin E. Huddleson, Jr. Professor of Law, who co-directed the Stanford Criminal Justice Center (SCJC) with Joan for 10 years. “Almost instantly she became a ‘pied piper’ to law students, convincing them they could become apprentice social scientists and could deliver constructive lessons about reform directly to policymakers. She built bridges between the academic world and the day-to-day world of police, prosecutors, parole and probation officers, and prison wardens, and she taught her students to traverse those bridges.”

“Joan was a giant intellect whose contributions to improving our criminal justice system are immense and will thankfully survive us all. I was honored to know and work with her.” says former California Governor Jerry Brown.

“For all of her brilliance and achievements, she stood out most of all for her genuineness, warmth, and generosity of spirit. The national and international worlds of criminology will also be mourning and celebrating Joan, but we at Stanford Law School can both proudly and gratefully claim to be the place where she did some of her greatest work,” says Jenny Martinez, Richard E. Lang Professor of Law and Dean of Stanford Law School. “At a personal level, she leaves a giant hole in our community because she was such a cherished colleague and friend.”

“Joan was one of kind.  Her work was deeply compassionate, but at the same time scrupulously objective and nonpartisan. No one knew more, or cared more intensely, about what actually happened to people convicted of crimes in the United States. No one thought harder or with greater sophistication about how to make prisons, jails, parole, and probation work better and more humanely,” says David A. Sklansky, Stanley Morrison Professor of Law at Stanford, who joined the SCJC team that included Petersilia, Weisberg, and executive director Debbie Mukamal in 2014.

After receiving her graduate degree in sociology, Petersilia began her career at the RAND Corporation, where she was director of the Criminal Justice Program, publishing landmark works including Crime and Public Policy (a series, now in its fourth edition, that she edited with renowned political scientist James Q. Wilson), Community Corrections, and California’s Correctional Paradox of Excess and Deprivation.

“Joan and I joined RAND at just about the same time, in the early 1970s,” says Deborah R. Hensler, the Judge John W. Ford Professor of Dispute Resolution at Stanford Law School. “The early 1970s at RAND offered exciting opportunities for empirical research on domestic policy issues but opportunities for women to assume leadership positions were far more limited. It was a great tribute to Joan’s analytic expertise, communication skills, managerial instincts, and interpersonal style that RAND appointed her the director of its Criminal Justice Program.”

While at RAND, Petersilia finished her doctorate in criminology at the University of California, Irvine, and in 1992 became a member of the faculty, where she taught PhD students in the School of Social Ecology and was the founding director of UCI’s Center for Evidence-Based Corrections. She published When Prisoners Come Home in 2003—and her work came to the attention of California’s then-governor, Arnold Schwarzenegger. She served as a special advisor to him, helping to reorganize juvenile and adult corrections and working with the California State Legislature to implement prison and parole reform.

Petersilia first came to Stanford Law School in 2005 as a visiting professor teaching California’s Prison Reform and Crime & Punishment in Calif.: Advocacy & Reform. She joined the faculty in 2009 and quickly found her way to the SCJC, becoming a faculty co-director.

Petersilia’s expertise was put to the test when in 2011 California passed some of the most innovative criminal justice reform in the country. The U.S. Supreme Court’s 2011 decision Brown v. Plata put immediate pressure on California by ordering the prison system’s population reduced by approximately 30,000 (to 137.5 percent of its capacity) by 2013. The state’s response to that pressure was AB 109. Signed into law by Governor Brown in the spring of 2011, it shifted responsibility for certain lower-level offenders from state to county authority, “realigning” the prison population.

Petersilia was soon asked to help in studying the effects of realignment, so she enlisted Stanford Law students to research the issues  through a practicum, which looked at Santa Clara County’s efforts to implement the new legislation. The practicum’s clients were then- California attorney general, Kamala Harris, and the California Department of Corrections and Rehabilitation. “Joan was a trusted advisor, and I will remember her brilliance, integrity, and warmth. Her advice and insights on advancing the field of criminal law when I was attorney general of California were invaluable and will serve me the rest of my career. California and the country is in her debt,” says Harris, now a U.S. senator, recalling her time working with Petersilia.

“Scholars and policy leaders know of Joan’s massive contributions to the field of criminal law, of course. But thousands and thousands more across the country, who may not know her name, are freer and safer because of her work,” says Michael Romano, JD ’03, founding director of the Stanford Law Three Strikes Project.

“As one of the founding mothers of de-carceration in California, Joan deservedly commanded respect from Republicans and Democrats, crime victims and inmate advocates,” says Keith Humphreys, Esther Ting Memorial Professor at Stanford, who shared research interests and a commitment to doing applied research with Petersilia. “Joan taught her students that before anything else happens—investigation, arrest, charges, trial, sentencing—there is always a victim, who like the accused has rights that the system is obligated to uphold.”

People close to Petersilia know how dedicated she was to her sons, both of whom have developmental disabilities. But few know that she put her scholarly skills to use in helping them too. She was active in the area of law and the developmentally disabled, particularly in the 1980s and 1990s when mainstreaming from state facilities into community-based homes raised a number of troubling issues. Indeed, for years, Petersilia was the pre-eminent, and often only, scholar working with The ARC of the U.S. (the largest national community-based organization advocating for and with people with intellectual and developmental disabilities (I/DD)).

Petersilia pulled away from that research in about 2005 after her direct work with policymakers dramatically increased. Alison Morantz, the James and Nancy Kelso Professor of Law and founding director of the Stanford Intellectual and Developmental Disabilities Law and Policy Project (SIDDLAPP), picked up the baton from Petersilia last year, turning her own empirical scholarship toward research in this area. Says Morantz, “I learned that before Joan came to Stanford, she blazed a trail as the first—and to this day, the leading—expert on the treatment of people with I/DD in the criminal justice system.”

But it was teaching students that Petersilia was most passionate about.

“She wanted them to understand the myriad viewpoints and issues arising from the criminal justice system so she took them to visit state prisons and local jails, specialty courts, and juvenile detention facilities and invited formerly incarcerated people, victims of crime, probation officers, parole board members, and other stakeholders to share their perspectives in her classes. Perhaps most importantly, though, Joan was deeply kind and caring. She supported those around her with an infectious enthusiasm,” says Mukamal.

“She insisted on evidence-based practices, and her research demonstrated why criminal justice systems failed when guided not by data, but by people’s punitive instincts and prejudices,” says Maggie Filler, JD ’12, now a civil rights attorney at the MacArthur Justice Center and in the law clinic at Northwestern Law School in Chicago.

“Joan was more than a professor to me. She was an educator and a life-long learner who modeled what pursuing your passions with inquisitiveness and healthy skepticism really looks like,” says Angela McCray, JD ’13, now general counsel at Entangled Group in New York, who worked with Petersilia and the SCJC to launch and run Project ReMADE to help formerly incarcerated individuals succeed in starting businesses of their own.

“I have advocated for the rights of prisoners on death row, children sentenced to die in prison, and, now, detained immigrants, and my work every day can be traced back to those first eye-opening classes with Joan,” says Mark Feldman, JD ’14, senior attorney at the Capital Area Immigrants’ Rights (CAIR) Coalition.

“There are three things in particular that make me feel so deeply lucky to have worked with Joan. First, she was an inspiring teacher and mentor. Second, she created meaningful opportunities for students to participate in incredibly sophisticated ‘real-world’ work. Third, she created a community for criminal justice students to connect,” says Jessica Greenlick Snyder, JD ’13, an attorney with the Federal Public Defender’s Office in Portland, Oregon.

David Ball, JD ’06, associate professor of law at Santa Clara University School of Law and co-chair of the Corrections Committee of the American Bar Association’s Criminal Justice Section, recalls Petersilia as a mentor. “She changed the course of my life. There is comfort, too, in the ripple effect of her life that she may not have even realized—the way I teach my law and policy classes, the way her influence shaped my approach to—and desire to be engaged with—policy.”

“She was a giant in the field. She was also a giant in my life. She helped me see that with a little passion and hard work, a lawyer like me could have a tremendous effect on criminal justice policy,” says John Butler, JD ’14, associate director at the Center for Court Innovation in New York. “It is because of her that I pursued criminal justice policy as a career. I am smarter, better, and more thoughtful thanks to her love and guidance.” SL