The 2005 U.S. Supreme Court decision Kelo v New London allows using eminent domain to transfer property from one private party to another when it serves a broadly defined public purpose such as economic development. This paper examines the effect of this doctrine on the size of state and local governments. In the leviathan model, constitutional constraints are needed to control government expansion. The Kelo decision removes one such constitutional constraint on how state and local governments gain command over privately owned resources. The empirical results show that the breadth of eminent domain power affects the size of the public sector; states that explicitly empower their local governments to use eminent domain for private economic development have larger state and local public sectors than those that do not.