McNeil v. United States presents an interesting question. Assume a person is convicted of a state offense in 2005 that has a certain punishment. In 2006, the state law is changed, and results in a lesser punishment. In 2010 the same person is convicted of a federal offense. The earlier offense triggers the Armed Career Criminal Act. Which version of the state act should inform the ACCA calculation? The 2005 version in effect at the time of commission of the crime? Or the 2006 version, in effect at the time of the sentencing. The Court went with the former. While there was a lengthy discussion about how the statute is phrased (in the present tense, not the past tense), here is a key paragraph from Justice Thomas’ majority opinion.

It cannot be correct that subsequent changes in statelaw can erase an earlier conviction for ACCA purposes. A defendant’s history of criminal activity—and the culpabil-ity and dangerousness that such history demonstrates—does not cease to exist when a State reformulates its criminal statutes in a way that prevents precise transla-tion of the old conviction into the new statutes. Congressbased ACCA’s sentencing enhancement on prior convic-tions and could not have expected courts to treat thoseconvictions as if they had simply disappeared. To the contrary, Congress has expressly directed that a prior violent felony conviction remains a “conviction” unless ithas been “expunged, or set aside or [the] person has beenpardoned or has had civil rights restored.” 18 U. S. C. §921(a)(20); see also Custis v. United States, 511 U. S. 485, 491 (1994) (explaining that §921(a)(20) “creates a clear negative implication that courts may count a conviction that has not been set aside”).

In other words, when someone is convicted of an offense, the offense, and resultant punishment, is effectively chiseled in stone unless it is expressly expunged. Future changes to the law cannot change that simple fact.

From a practical perspective, it makes little sentence for two people in identical circumstances to receive different punishments based on whether the sentencing was before, or after the state law was changed.

In addition, McNeill’s interpretation would make ACCA’s applicability depend on the timing of the federalsentencing proceeding. McNeill cannot explain why twodefendants who violated §922(g) on the same day and who had identical criminal histories—down to the dates on which they committed and were sentenced for their prior offenses—should receive dramatically different federal sentences solely because one’s §922(g) sentencing hap-pened to occur after the state legislature amended the punishment for one of the shared prior offenses. In con-trast, the interpretation we adopt permits a defendant to know even before he violates §922(g) whether ACCA would apply.