Mr. Sunstein, a prolific academic with wide-ranging interests, may be best known for advancing a field known as "law andbehavioraleconomics" that seeks to shape lawand policy around the way research shows people actually behave.
In an interview with The Wall Street Journal last year, Mr. Sunstein said Mr. Obama was intrigued by "law andbehavioraleconomics" as an approach to regulation that would avoid ideological extremes.