David Dow is a law professor at the University of Houston Law Center and Litigation Director of the Texas Defender Service. His latest book The Autobiography of an Execution (Amazon) was just published last week.
Prof. Dow also had an excellent article in the Houston Law Review: The Last Execution: Rethinking the Fundamentals of Death Penalty Law, 45 Hous. L. Rev. 963 (2008) (pdf).