In his latest book, Republic of Debtors: Bankruptcy in the Age of American Independence (winner 2003 SHEAR Book Prize; 2004 J. Willard Hurst Prize, awarded by Law and Society Association; and 2003 Littleton-Griswold Prize, awarded by the American Historical Association), Mann explores the legal, social, economic, moral, political and intellectual implications of debt and failure in the early American republic, revealing how problems of money, credit, and debt implicated questions of commerce and agriculture, nationalism and federalism, dependence and independence, even slavery and freedom.

Mann has been the keynote speaker at the annual conference of the Australia and New Zealand Law and History Society, and the annual convention of the National Association of Consumer Bankruptcy Attorneys. His four teaching awards include three at Penn: the A. Leo Levin Award for Excellence in an Introductory Law Course; the Harvey Levin Memorial Award for Excellence in Teaching at the law school; and the university-wide Christian R. and Mary F. Lindback Foundation Award for Distinguished Teaching.

Mann is married to Elizabeth Warren, who is the Leo Gottlieb Professor of Law at Harvard Law School.