A political interpretation of vagueness doctrine

What conduct can be punished as a crime, and who can proscribe such crimes? American constitutional law appears to say little about either question. To be sure, punishment must be for past conduct,1 previously proscribed,2 and some conduct is protected by fundamental rights.3 Yet constitutional law says little more about what conduct can be punished.4 It does not, as some theorists have proposed, restrict crimes to acts harming or threatening a legal interest.5 Moreover, unlike the many countries requiring legislative criminalization,6 the United States has no constitutional requirement that criminal offenses be defined by one branch of government. Thus, the Constitution does not preclude criminalization by state courts,7 or executive agencies.8 In this Article, however, we will argue that there is a doctrine of American constitutional law that imposes a practical limit on what kinds of conduct can be criminalized, and on who can make that decision: The doctrine of unconstitutional vagueness, requiring that criminal prohibitions be specific enough to provide notice to those who must obey them and to cabin the discretion of those who enforce them.9.