It is a bedrock principle of American criminal law that the authority to try and punish someone for a crime arises from the crime’s connection to a particular place. Thus, we assume that a person who commits a crime in some location— say, Philadelphia—can be arrested by Philadelphia police for conduct deemed criminal by the Pennsylvania legislature, prosecuted in a Philadelphia court, and punished in a Pennsylvania prison. The idea that criminal law is tied to geography in this way is called the territoriality principle. This idea is so familiar that it usually goes unstated.

This Article foregrounds and questions the territoriality principle. Drawing on a broad and eclectic set of sources, it argues that domestic criminal law is less territorial than conventional wisdom holds. Although the territoriality principle is central to criminal law ideology, territorialism is a norm in decline. In reality, over the past century, new doctrines and enforcement practices have unmoored criminal law from geographic boundaries. The result is a criminal legal system in which borders are negotiable and honored in the breach.

Scholars have largely overlooked the deterritorialization of domestic criminal law, but the decline of the territoriality principle has striking implications. It undermines constitutional doctrines and academic theories built on the classic account of criminal law. It upsets foundational conceptual distinctions that structure public law. And it raises normative questions about just how far criminal laws should reach. This Article grapples with those questions and argues that borders are an underenforced constraint on the police power.