Tax Policy and the Economy, Volume 15 2001 HKS Authors See citation below for complete author information. Jeffrey Liebman Director of the Taubman Center for State and Local Government Malcolm Wiener Professor of Public Policy David Ellwood Isabelle and Scott Black Professor of Political Economy; Harvard University Distinguished Service Professor Citation Ellwood, David, and Jeffrey Liebman. "The Middle Class Parent Penalty: Child Benefits in the U.S. Tax Code." Tax Policy and the Economy, Volume 15. Ed. James M. Poterba. MIT Press, 2001.