Associate Justice Mariano-Florentino Cuéllar

Justice Mariano Florentino Cuellar

[Left the bench effective October 31, 2021]

Justice Cuéllar began serving on California’s highest court in January 2015. Previously, he was the Stanley Morrison Professor of Law, Professor (by courtesy) of Political Science, and Director of the Freeman Spogli Institute for International Studies at Stanford University. A fellow of the American Academy of Arts and Sciences, Cuéllar is a scholar of public law, complex organizations, and institutions whose research explores problems in administrative law and legislation, cyberlaw and artificial intelligence, public health and safety, and international affairs. As Director of the Freeman Spogli Institute, Cuéllar led Stanford’s principal institution for the study of international affairs, with centers and programs focused on governance and development, international security, health and environmental policy, and education. He grew the Institute’s faculty, launched university-wide initiatives on global poverty and cyber security, expanded nuclear security research, and increased support for undergraduate and graduate students. 

In the Obama administration, Justice Cuéllar led the White House Domestic Policy Council’s teams responsible for civil and criminal justice, public health, and immigration, as well as its efforts to repeal the military’s Don’t Ask/Don’t Tell policy and enact bipartisan public health, food safety, and sentencing reform legislation (2009-2010). He also led the Presidential Transition Task Force on Immigration (2008-2009), and co-chaired the U.S. Department of Education’s Equity and Excellence Commission (2011-2013). He serves on the boards of Harvard University (the President & Fellows of Harvard College), the Hewlett Foundation, and the American Law Institute, and chairs the boards of the Center for Advanced Study in the Behavioral Sciences and Stanford Seed. Within the California judiciary, he led the statewide Language Access Implementation Task Force (2015-2019) to improve services for California’s millions of limited-English speakers. 

A naturalized U.S. citizen born in northern Mexico, he attended a public high school in California’s Imperial Valley before graduating from Harvard and Yale Law School, and receiving a Ph.D in political science from Stanford. He began his legal career at the U.S. Treasury Department and clerked for Chief Judge Mary Schroeder of the U.S. Court of Appeals for the Ninth Circuit. He is married to Judge Lucy H. Koh of the U.S. District Court for the Northern District of California.