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Associate Justice, State of California Supreme Court

Mariano-Florentino Cuéllar

Justice Cuéllar began serving on the Supreme Court of California 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 political economy whose work explores problems in administrative law and legislation, cyberlaw and artificial intelligence, public health and safety law, 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 cybersecurity to support the creation of new research centers; expanded the Institute’s research on nuclear security, health, and education; 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 successful 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 chairs the boards of the Center for Advanced Study in the Behavioral Sciences and Stanford Seed and is a member of the Harvard Corporation (President & Fellows of Harvard College), the Hewlett Foundation Board of Directors, and the Council of the American Law Institute. 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.