Lochner v. New York (1905), which pitted a conservative activist judiciary against a reform-minded legislature, remains one of the most important and most frequently cited cases in Supreme Court history. In this concise and readable guide, Paul Kens shows us why the case remains such an important marker in the ideological battles between the free market and the regulatory state.

Paul Kens is a professor of political science and history at Texas State University-San Marcos. He frequently writes on subjects involving legal history, constitutional history, and the history of law in the American West. His books include Lochner v. New York: Economic Regulation on Trial and Justice Stephen Field: Shaping Liberty from the Gold Rush to the Gilded Age.