Cass Robert Sunstein (born 21 September 1954) is an American legal scholar, particularly in the fields of constitutional law, administrative law, environmental law, and law and behavioral economics. He is also The New York Times best-selling author of The World According to Star Wars (2016) and Nudge (2008). He was the Administrator of the White House Office of Information and Regulatory Affairs in the Obama administration from 2009 to 2012.