Notable statutory interpretation embrace of a basic offense/offender distinction for elements and sentencing factors

As long-time readers or hard-core sentencing fans may know, when I was first trying to make sense of Blakely, I was drawn to distinguishing between offense conduct and offender characteristics in the application of Apprendi's "bright-line rule."  I first developed this idea in my Conceptualizing Blakely article, advanced it in a StanfordLaw Review article, and further unpacked it (with Stephanos Bibas) in Making Sentencing Sensible article in the Ohio State Journal of Criminal Law.  As explained in Conceptualizing Blakely, I believe an offense/offender distinction helps give conceptual content to the prior conviction exception, better links the Apprendi rule to the express text of the Constitution, and resonates with the distinctive institutional competencies of juries and judges.

As detailed in this post right after the Supreme Court's 2007 Sixth Amendment ruling in Cunningham v. California, Justice Kennedy's dissenting opinion in Cunningham praised an offense/offender distinction as providing a "principled rationale" for the application of the Apprendi rule: "The Court could distinguish between sentencing enhancements based on the nature of the offense, where the Apprendi principle would apply, and sentencing enhancements based on the nature of the offender, where it would not."  But Justice Kennedy was writing in dissent and footnote 14 of Justice Ginsburg's majority opinion in Cunningham  asserts that "Apprendi itself ... leaves no room for the bifurcated approach Justice Kennedy proposes."

Against this backdrop, I found especially interesting and notable this passage from the Court's opinion today in O'Brien (which just happens to be authored by Justice Kennedy):

Sentencing factors traditionally involve characteristics of the offender — such as recidivism, cooperation with law enforcement, or acceptance of responsibility.  [Castillo, 530 U.S.] at 126. Characteristics of the offense itself are traditionally treated as elements, and the use of a machinegun under §924(c) lies “closest to the heart of the crime at issue.” Id., at 127.

As the cites reveal, the Supreme Court made a somewhat similar set of statements a decade ago in its Castillo ruling.  But this O'Brien articulation of an offense/offender distinction for statutory interpretation purposes seems especially crisp and clean here.  Perhaps in the future Justice Kennedy might be able to get a few of the new Justices to give this distinction constitutional significance in some future elaborations of the Apprendi/Blakely line of decisions.