Whether ACCA's residual clause is unconstitutionally vague under the Fifth Amendment's Due Process Clause.
Holding
Yes. The residual clause is void for vagueness because it denies fair notice and invites arbitrary enforcement.
Reasoning
Due process forbids criminal laws so vague that ordinary people lack fair notice of what the law punishes or that they authorize arbitrary enforcement. That rule applies not only to statutes defining crimes but also to statutes that fix criminal sentences. Because the residual clause could increase a defendant's punishment from a maximum of 10 years to a minimum of 15 years and potentially life, it had to satisfy this constitutional requirement.
Under ACCA's categorical approach, courts do not examine the defendant's actual conduct in committing the prior offense. They instead identify the crime's imagined “ordinary case” and decide whether that abstraction presents a serious potential risk of physical injury. The Court concluded that the statute gave judges no reliable method for determining what the ordinary version of an offense looks like or how its possible consequences should be assessed.
The clause also failed to specify how much risk was enough. Courts had to measure an imagined ordinary case against burglary, arson, extortion, and crimes involving explosives, but those listed offenses themselves vary greatly in their ordinary forms and levels of danger. Combining uncertainty about how to estimate risk with uncertainty about the required degree of risk produced intolerable unpredictability.
The Court's own residual-clause decisions confirmed the problem. James used an analogy to completed burglary; Chambers relied on a Sentencing Commission report; Sykes invoked common sense and statistics; and Begay required similarity in kind as well as risk. These shifting, ad hoc tests did not yield a generally applicable standard for the many state and federal offenses potentially subject to ACCA.
Lower-court decisions likewise revealed disagreement not merely at the margins, but about the basic inquiry itself. Courts differed over whether to consider the likelihood that a conspiracy would be completed, how a police officer would respond to a minor battery, and what age differences to assume in statutory-rape cases. That persistent conflict showed that the residual clause had become a judicial morass rather than a workable legal rule.
The existence of some plainly dangerous offenses did not save the clause. A provision may be vague even if certain conduct plainly falls within its language; otherwise, statutes invalidated for terms such as “unjust or unreasonable” prices or “annoying” conduct could have survived based on obvious examples. The constitutional defect was the clause's failure to provide a principled standard across its applications.
The ruling did not cast doubt on ordinary statutes that apply qualitative risk standards to a defendant's real-world conduct on a particular occasion. The distinctive flaw here was the need to apply an uncertain risk standard to a judicially constructed, idealized ordinary case of a prior crime.