Cass Sunstein is Robert Walmsley University Professor of law and ​​founder and director of the Program on Behavioral Economics and Public Policy at Harvard Law School. He is author of numerous books, including #Republic: Divided Democracy in the Age of Social Media (Princeton University Press, 2018); Law and Leviathan: Redeeming the Administrative State (Harvard University Press, 2020); and Impeachment: A Citizen's Guide (Penguin Books, 2019).