Carey earned his bachelor's degree at Harvard University, then worked on the legislative staff of Senator John F. Kerry before pursuing his Ph.D. in political science at the University of California, San Diego. He spent five summers as a commercial salmon fisherman in Kasilof, Alaska, before resigning himself fully to academia. Before coming to Dartmouth, Carey held faculty appointments at the University of Rochester and at Washington University in St. Louis. He served as chair of Dartmouth's Department of Government from 2009-2015, and as associate dean of faculty for the social sciences division from 2019-2024. Carey has also taught at the Catholic University of Chile, at Harvard, and at the Fundacion Juan March in Madrid, Spain. He has consulted on the design and reform of electoral systems in Canada, Nepal, Afghanistan, Jordan, Tunisia, Yemen, South Sudan, Israel, Mexico, Bolivia, El Salvador, and the Philippines.
Carey's research and teaching focus on representation and elections, Latin American politics, and U.S. politics. He teaches classes on comparative politics, elections, threats to democracy, and foreign aid. He has written or co-authored six books, including Campus Diversity: The Hidden Consensus (2020), Legislative Voting & Accountability (2009) and Presidents and Assemblies: Constitutional Design and Electoral Dynamics (1992), as well as over 100 journal articles, book chapters, essays, and reports. Since 2020, his research has been published in Science Advances, Nature Human Behavior, PNAS-Nexus, the Quarterly Journal of Political Science, the British Journal of Political Science, Electoral Studies, Political Behavior, and other journals.
Carey's research has been supported by the National Science Foundation, the Hewlett Foundation, the Democracy Fund, the Packard Foundation, and other sources. In 2012, he was elected to the American Academy of Arts and Sciences. In 2014, his 1992 book with Matthew Shugart, Presidents and Assemblies, was given the George Hallet H. Award from the American Political Sciences Association, for a lasting contribution to the understanding of representation and electoral systems.
In 2017, Carey co-founded Bright Line Watch, which monitors democratic performance, erosion, and resilience in the United States. BLW's reports and its surveys of the general public and of academic experts provide an authoritative account of the state of American democracy and public support for it, and are regularly covered in the national press. All BLW data are publicly available and BLW's work contributes to university curricula via the Democratic Erosion Consortium.
Carey's wife, Lisa Baldez, is also a Professor of Government at Dartmouth. Their sons, Joe and Sam, are proud Dartmouth alumni. Joe ('15, Economics) is a Major and an aviator in the United States Marine Corps. Sam ('18, Mathematics) is a lead consultant with Celonis, a process mining firm.