Under what conditions can US courts contribute to policy change? This article shows how a case study can be used to test and develop a theory of judicial policy making answering this question. In The Hollow Hope (1991, 2008), Gerald Rosenberg theorizes that judicial policy making is constrained by the limited nature of constitutional rights, the lack of judicial independence, and the judiciary's inability to implement its rulings. Ninth Circuit injunctions protecting the Northern Spotted Owl and orders to manage ecosystems in the Pacific Northwest invalidate and help reformulate Rosenberg's theory. These rulings show how judicial interpretations of statutes, regulations, precedent, and facts allow judicial policy making if these interpretations are accepted by the legal and political culture when Congress and the presidency are too divided to override them. The owl rulings also show how statutes facilitate the implementation of judicial rulings, a point not developed by Rosenberg, while additionally providing further evidence for Rosenberg's specification of conditions allowing implementation.