The vagueness of the residual clause of the Armed Career Criminal Act of 1984 rests in large part on its operation under the categorical approach. The categorical approach is the framework the U.S. Supreme Court has applied in deciding whether an offense qualifies as a violent felony under the Armed Career Criminal Act. Under the categorical approach, a court assesses whether a crime qualifies as a violent felony in terms of how the law defines the offense and not in terms of how an individual offender might have committed it on a particular occasion. For purposes of the residual clause, then, courts were to determine whether a crime involved a serious potential risk of physical injury by considering not the defendant's actual conduct but an idealized ordinary case of the crime. The Court's analysis in Johnson thus cast no doubt on the many laws that require gauging the riskiness of conduct in which an individual defendant engages on a particular occasion. The residual clause failed not because it adopted a "serious potential risk" standard but because applying that standard under the categorical approach required courts to assess the hypothetical risk posed by an abstract generic version of the offense.
Federal law made the possession of a firearm by a felon a crime punishable by a prison term of up to 10 years. However, the Armed Career Criminal Act of 1984 increased that sentence to a mandatory 15 years to life if the offender had three or more prior convictions for a "serious drug offense" or a "violent felony." The definition of "violent felony" included the so-called residual clause, covering any felony that "otherwise involves conduct that presents a serious potential risk of physical injury to another.” In Johnson v. United States, the Supreme Court of the United States held that the residual clause was unconstitutional under the void-for-vagueness doctrine.
Petitioner Welch was sentenced under the Armed Career Criminal Act before Johnson was decided. On direct review, the United States Court of Appeals for the Eleventh Circuit affirmed his sentence, holding that Welch's prior Florida conviction for robbery qualified as a "violent felony" under the residual clause. After his conviction became final, Welch sought collateral relief under 28 U.S.C.S. §2255, which the district court denied. The Eleventh Circuit then denied Welch a certificate of appealability. Three weeks later, the Court decided Johnson. Welch sought retroactive application of Johnson to his case.
Should Johnson v. United States apply retroactively to a prisoner's case on collateral review?
The Court held that Johnson v. United States changed the substantive reach of the Act and was therefore a substantive decision. It was not a procedural decision, as it affected the reach of the underlying statute rather than the judicial procedures by which the statute was applied. As a new substantive rule, it had retroactive effect in cases on collateral review. The Teague balance did not depend on whether the underlying constitutional guarantee was procedural or substantive, but instead on whether the new rule itself had a procedural or substantive function. It was not necessary for the new rule to limit Congress' power in order to be substantive. The case was remanded.