Opening with the case of United States v. Campbell, a case from the Court of Appeals for the Eleventh Circuit involving a real estate broker charged with money laundering, this chapter offers two stories. The first, involving a fictional king named Rex, illustrates the extent to which criminal law theorists (and citizens more generally) disagree about what justice requires across a range of rules governing the imposition of state punishment. In light of such disagreement, how is Rex to decide what, as a matter of justice, the criminal law should be? The second story, involving an imaginary island named Anarchia, illustrates how state authority provides an important good—authoritatively resolving reasonable disagreements among free and equal democratic citizens about the requirements of justice—and explains why those subject to a democratic state’s authority are morally bound to conform their conduct to the law resolving those disagreements. It then argues that a democratic state’s authority to resolve disagegreements among its citizens over the demands of justice is nonetheless limited authority. A democratic state has wide authority, but not unlimited authority. The actus reus and mens rea requirements limit the authority of a democratic state to ascribe guilt.