The peculiar harshness of modern American justice has led to a vigorous scholarly debate about the roots of mass incarceration and its divergence from humanitarian sentencing norms prevalent in other Western democracies. Even though the United States reached virtually world-record imprisonment levels between 1983 and 2010, the Supreme Court never found a prison term to be “cruel and unusual punishment” under the Eighth Amendment. By countenancing extreme punishments with no equivalent elsewhere in the West, such as life sentences for petty recidivists, the Justices’ reasoning came to exemplify the exceptional nature of American justice. Many scholars concluded that punitiveness had become its defining norm.
Yet a quiet revolution in Eighth Amendment jurisprudence, a wave of reforms, and other social developments suggest that American penal philosophy may be inching toward norms—dignity, proportionality, legitimacy, and rehabilitation—that have checked draconian prison terms in Europe, Canada, and beyond. In 2010, the Supreme Court began limiting the scope of life imprisonment without parole for juveniles in a series of landmark Eighth Amendment cases. Partly drawing upon the principles in these decisions, twenty-two states have abolished life without parole categorically for juveniles, providing them more protections than under the Eighth Amendment. The narrow focus on the differences between juveniles and adults in the aftermath of these reforms obscured American law’s increasing recognition of humanitarian norms that are hardly age-dependent—and strikingly similar to those in other Western democracies. Historiography sheds light on why the academy has largely overlooked this relative paradigm shift. As America faced mass incarceration of an extraordinary magnitude, research in recent decades has focused on divergence, not convergence.
This Article advances a comparative theory of punishment to analyze these developments. In the United States and throughout the West, approaches toward punishment are impermanent social constructs, as they historically tend to fluctuate between punitive and humanitarian concerns. Such paradigm shifts can lead to periods of international divergence or convergence in penal philosophy. Notwithstanding the ebb and flow of penal attitudes, certain long-term trends have emerged in Western societies. They encompass a narrowing scope of offenders eligible for the harshest sentences, a reduction in the application of these sentences, and intensifying social divides about their morality. Restrictions on lifelong imprisonment for juveniles and growing social polarization over mass incarceration in the United States may reflect this movement. However, American justice appears particularly susceptible to unpredictable swings and backlashes. While this state of impermanence suggests that the reform movement might reverse itself, it also demonstrates that American justice may keep converging toward humanitarian sentencing norms, which were influential in the United States before the mass incarceration era.
Two patterns regarding the broader evolution of criminal punishment ultimately stand out: cyclicality and steadiness of direction. The patterns evoke a seismograph that regularly swings up or down despite moving steadily in a given direction. American justice may cyclically oscillate between repressive or humanitarian aspirations, and simultaneously converge with other Western democracies in gradually limiting or abolishing the harshest punishments over the long term.