PhD, Duke University, 1991. Professor of law, Duke Law faculty, Duke University, Durham NC, May 2012 - and 7/1989-6/2010. Deputy assistant attorney general, Office of Legal Counsel, U.S. Department of Justice, 1993-2000. Professor, George Washington University Law School, 8/2010-4/2012. Professor of Law, 5/1988-4/1989; Associate Professor, 6/1984-5/1988, University of Iowa