Jan is Roger Williams Straus Professor of Social Sciences and Professor of Politics at Princeton University. He works mainly in democratic theory and the history of modern political thought; he also has a research interest in the relationship between architecture and politics, as well as the normative implications of the current structural transformations of the public sphere. Publications include Constitutional Patriotism (2007) and What is Populism? (2016), which has been translated into more than twenty languages. 2019 saw the publication of Furcht und Freiheit: Für einen anderen Liberalismus, which won the Bavarian Book Prize. He is also a columnist for the Guardian in the US and writes regularly for the London Review of Books.

At THE NEW INSTITUTE Jan was involved in the program "The Future of Democracy".