Cass R. Sunstein (b. 1954) is a prominent liberal law professor at the University of Chicago.
His 2001 book, Republic.com, argued that the Internet threatens democracy because it allows citizens to isolate themselves within groups that share their own views and experiences, and thus cut themselves off from any information that might challenge their beliefs, a phenomenon often known by the term cyberbalkanization .
His latest book, The Second Bill of Rights: FDR's Unfinished Revolution and Why We Need It More than Ever, discusses the little-known Second Bill of Rights proposed by President Franklin Delano Roosevelt.
Sunstein is a contributing editor to The New Republic. He has been romantically linked to Chicago philosopher Martha Nussbaum.